Package icyllis.modernui.widget

Class NestedScrollView

java.lang.Object

icyllis.modernui.view.View

icyllis.modernui.view.ViewGroup

icyllis.modernui.widget.FrameLayout

icyllis.modernui.widget.NestedScrollView

All Implemented Interfaces:

Drawable.Callback, ViewManager, ViewParent

public class NestedScrollView
extends FrameLayout

NestedScrollView is just like ScrollView, but it supports nested fling and nested scrolling by mouse wheel invalid input: '&' touchpad (normal ScrollView and ListView only supports nested scrolling by dragging). Nested scrolling is enabled by default.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	NestedScrollView.OnScrollChangeListener	Interface definition for a callback to be invoked when the scroll X or Y positions of a view change.

Nested classes/interfaces inherited from class icyllis.modernui.widget.FrameLayout

FrameLayout.LayoutParams

Nested classes/interfaces inherited from class icyllis.modernui.view.ViewGroup

ViewGroup.MarginLayoutParams

Nested classes/interfaces inherited from class icyllis.modernui.view.View

View.DragShadow, View.Focusable, View.FocusableMode, View.FocusDirection, View.FocusRealDirection, View.LayoutDir, View.NestedScrollType, View.OnAttachStateChangeListener, View.OnClickListener, View.OnContextClickListener, View.OnCreateContextMenuListener, View.OnDragListener, View.OnFocusChangeListener, View.OnGenericMotionListener, View.OnHoverListener, View.OnKeyListener, View.OnLayoutChangeListener, View.OnLongClickListener, View.OnTouchListener, View.ResolvedLayoutDir, View.ScrollAxis, View.ScrollBarStyle, View.ScrollIndicators, View.TextAlignment, View.Visibility

Field Summary

Fields inherited from class icyllis.modernui.view.ViewGroup

CLIP_TO_PADDING_MASK, FLAG_DISALLOW_INTERCEPT, FOCUS_AFTER_DESCENDANTS, FOCUS_BEFORE_DESCENDANTS, FOCUS_BLOCK_DESCENDANTS

Fields inherited from class icyllis.modernui.view.View

ALPHA, BOTTOM, EMPTY_STATE_SET, ENABLED_FOCUSED_SELECTED_STATE_SET, ENABLED_FOCUSED_SELECTED_WINDOW_FOCUSED_STATE_SET, ENABLED_FOCUSED_STATE_SET, ENABLED_FOCUSED_WINDOW_FOCUSED_STATE_SET, ENABLED_SELECTED_STATE_SET, ENABLED_SELECTED_WINDOW_FOCUSED_STATE_SET, ENABLED_STATE_SET, ENABLED_WINDOW_FOCUSED_STATE_SET, FOCUS_BACKWARD, FOCUS_DOWN, FOCUS_FORWARD, FOCUS_LEFT, FOCUS_RIGHT, FOCUS_UP, FOCUSABLE, FOCUSABLE_AUTO, FOCUSABLES_ALL, FOCUSABLES_TOUCH_MODE, FOCUSED_SELECTED_STATE_SET, FOCUSED_SELECTED_WINDOW_FOCUSED_STATE_SET, FOCUSED_STATE_SET, FOCUSED_WINDOW_FOCUSED_STATE_SET, GONE, HAPTIC_FEEDBACK_ENABLED, INVISIBLE, LAYOUT_DIRECTION_INHERIT, LAYOUT_DIRECTION_LOCALE, LAYOUT_DIRECTION_LTR, LAYOUT_DIRECTION_RTL, LAYOUT_DIRECTION_UNDEFINED, LEFT, MEASURED_HEIGHT_STATE_SHIFT, MEASURED_SIZE_MASK, MEASURED_STATE_MASK, MEASURED_STATE_TOO_SMALL, NO_ID, NOT_FOCUSABLE, OVER_SCROLL_ALWAYS, OVER_SCROLL_IF_CONTENT_SCROLLS, OVER_SCROLL_NEVER, PRESSED_ENABLED_FOCUSED_SELECTED_STATE_SET, PRESSED_ENABLED_FOCUSED_SELECTED_WINDOW_FOCUSED_STATE_SET, PRESSED_ENABLED_FOCUSED_STATE_SET, PRESSED_ENABLED_FOCUSED_WINDOW_FOCUSED_STATE_SET, PRESSED_ENABLED_SELECTED_STATE_SET, PRESSED_ENABLED_SELECTED_WINDOW_FOCUSED_STATE_SET, PRESSED_ENABLED_STATE_SET, PRESSED_ENABLED_WINDOW_FOCUSED_STATE_SET, PRESSED_FOCUSED_SELECTED_STATE_SET, PRESSED_FOCUSED_SELECTED_WINDOW_FOCUSED_STATE_SET, PRESSED_FOCUSED_STATE_SET, PRESSED_FOCUSED_WINDOW_FOCUSED_STATE_SET, PRESSED_SELECTED_STATE_SET, PRESSED_SELECTED_WINDOW_FOCUSED_STATE_SET, PRESSED_STATE_SET, PRESSED_WINDOW_FOCUSED_STATE_SET, RIGHT, ROTATION, ROTATION_X, ROTATION_Y, SCALE_X, SCALE_Y, SCROLL_AXIS_HORIZONTAL, SCROLL_AXIS_NONE, SCROLL_AXIS_VERTICAL, SCROLL_INDICATOR_BOTTOM, SCROLL_INDICATOR_END, SCROLL_INDICATOR_LEFT, SCROLL_INDICATOR_RIGHT, SCROLL_INDICATOR_START, SCROLL_INDICATOR_TOP, SCROLL_X, SCROLL_Y, SCROLLBARS_INSIDE_INSET, SCROLLBARS_INSIDE_OVERLAY, SCROLLBARS_OUTSIDE_INSET, SCROLLBARS_OUTSIDE_OVERLAY, SELECTED_STATE_SET, SELECTED_WINDOW_FOCUSED_STATE_SET, SOUND_EFFECTS_ENABLED, TEXT_ALIGNMENT_CENTER, TEXT_ALIGNMENT_GRAVITY, TEXT_ALIGNMENT_INHERIT, TEXT_ALIGNMENT_TEXT_END, TEXT_ALIGNMENT_TEXT_START, TEXT_ALIGNMENT_VIEW_END, TEXT_ALIGNMENT_VIEW_START, TEXT_DIRECTION_ANY_RTL, TEXT_DIRECTION_FIRST_STRONG, TEXT_DIRECTION_FIRST_STRONG_LTR, TEXT_DIRECTION_FIRST_STRONG_RTL, TEXT_DIRECTION_INHERIT, TEXT_DIRECTION_LOCALE, TEXT_DIRECTION_LTR, TEXT_DIRECTION_RTL, TOP, TRANSLATION_X, TRANSLATION_Y, TRANSLATION_Z, TYPE_NON_TOUCH, TYPE_TOUCH, VIEW_MARKER, VISIBLE, WINDOW_FOCUSED_STATE_SET, X, Y, Z

Constructor Summary

Constructors

Constructor	Description
NestedScrollView(Context context)

Method Summary

Modifier and Type	Method	Description
void	addView(View child)	Adds a child view.
void	addView(View child, int index)	Adds a child view.
void	addView(View child, int index, ViewGroup.LayoutParams params)	Adds a child view with the specified layout parameters.
void	addView(View child, ViewGroup.LayoutParams params)	Adds a child view with the specified layout parameters.
boolean	arrowScroll(int direction)	Handle scrolling in response to an up or down arrow click.
int	computeHorizontalScrollExtent()	Compute the horizontal extent of the horizontal scrollbar's thumb within the horizontal range.
int	computeHorizontalScrollOffset()	Compute the horizontal offset of the horizontal scrollbar's thumb within the horizontal range.
int	computeHorizontalScrollRange()	Compute the horizontal range that the horizontal scrollbar represents.
void	computeScroll()	Called by a parent to request that a child update its values for mScrollX and mScrollY if necessary.
protected int	computeScrollDeltaToGetChildRectOnScreen(Rect rect)	Compute the amount to scroll in the Y direction in order to get a rectangle completely on the screen (or, if taller than the screen, at least the first screen size chunk of it).
int	computeVerticalScrollExtent()	Compute the vertical extent of the vertical scrollbar's thumb within the vertical range.
int	computeVerticalScrollOffset()	Compute the vertical offset of the vertical scrollbar's thumb within the horizontal range.
int	computeVerticalScrollRange()	The scroll range of a scroll view is the overall height of all of its children.
boolean	dispatchKeyEvent(KeyEvent event)	Dispatch a key event to the next view on the focus path.
boolean	executeKeyEvent(KeyEvent event)	You can call this function yourself to have the scroll view perform scrolling from a key event, just as if the event had been dispatched to it by the view hierarchy.
void	fling(int velocityY)	Fling the scroll view
boolean	fullScroll(int direction)	Handles scrolling in response to a "home/end" shortcut press.
int	getMaxScrollAmount()
boolean	isFillViewport()	Indicates whether this ScrollView's content is stretched to fill the viewport.
boolean	isSmoothScrollingEnabled()
protected void	measureChild(View child, int parentWidthMeasureSpec, int parentHeightMeasureSpec)	Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding.
protected void	measureChildWithMargins(View child, int parentWidthMeasureSpec, int widthUsed, int parentHeightMeasureSpec, int heightUsed)	Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding and margins.
void	onAttachedToWindow()	This is called when the view is attached to a window.
void	onDrawForeground(Canvas canvas)	Draw any foreground content for this view.
boolean	onGenericMotionEvent(MotionEvent event)	Implement this method to handle generic motion events.
boolean	onInterceptTouchEvent(MotionEvent ev)	Implement this method to intercept all touch screen motion events.
protected void	onLayout(boolean changed, int l, int t, int r, int b)	Called from View.layout(int, int, int, int) when this view should assign a size and position to each of its children.
protected void	onMeasure(int widthMeasureSpec, int heightMeasureSpec)	Measure the view and its content to determine the measured width and the measured height.
boolean	onNestedFling(View target, float velocityX, float velocityY, boolean consumed)	Request a fling from a nested scroll.
void	onNestedScroll(View target, int dxConsumed, int dyConsumed, int dxUnconsumed, int dyUnconsumed, int type, int[] consumed)	React to a nested scroll in progress.
void	onNestedScrollAccepted(View child, View target, int axes, int type)	React to the successful claiming of a nested scroll operation.
protected void	onOverScrolled(int scrollX, int scrollY, boolean clampedX, boolean clampedY)	Called by View.overScrollBy(int, int, int, int, int, int, int, int, boolean) to respond to the results of an over-scroll operation.
protected boolean	onRequestFocusInDescendants(int direction, Rect previouslyFocusedRect)	When looking for focus in children of a scroll view, need to be a little more careful not to give focus to something that is scrolled off screen.
protected void	onScrollChanged(int l, int t, int oldl, int oldt)	This is called in response to an internal scroll in this view (i.e., the view scrolled its own contents).
protected void	onSizeChanged(int w, int h, int oldw, int oldh)	Called when width or height changed
boolean	onStartNestedScroll(View child, View target, int axes, int type)	React to a descendant view initiating a nestable scroll operation, claiming the nested scroll operation if appropriate.
boolean	onTouchEvent(MotionEvent ev)	Implement this method to handle touch screen motion events.
boolean	pageScroll(int direction)	Handles scrolling in response to a "page up/down" shortcut press.
void	requestChildFocus(View child, View focused)	Called when a child of this parent wants focus
boolean	requestChildRectangleOnScreen(View child, Rect rectangle, boolean immediate)	Called when a child of this group wants a particular rectangle to be positioned onto the screen.
void	requestDisallowInterceptTouchEvent(boolean disallowIntercept)	Called when a child does not want this parent and its ancestors to intercept touch events with ViewGroup.onInterceptTouchEvent(MotionEvent).
void	requestLayout()	Call this when something has changed which has invalidated the layout of this view.
void	scrollTo(int x, int y)	Set the scrolled position of your view.
void	setFillViewport(boolean fillViewport)	Set whether this ScrollView should stretch its content height to fill the viewport or not.
void	setOnScrollChangeListener(NestedScrollView.OnScrollChangeListener l)	Register a callback to be invoked when the scroll X or Y positions of this view change.
void	setSmoothScrollingEnabled(boolean smoothScrollingEnabled)	Set whether arrow scrolling will animate its transition.
boolean	shouldDelayChildPressedState()	Return true if the pressed state should be delayed for children or descendants of this ViewGroup.
final void	smoothScrollBy(int dx, int dy)	Like View.scrollBy(int, int), but scroll smoothly instead of immediately.
final void	smoothScrollBy(int dx, int dy, int scrollDurationMs)	Like View.scrollBy(int, int), but scroll smoothly instead of immediately.
final void	smoothScrollTo(int x, int y)	Like scrollTo(int, int), but scroll smoothly instead of immediately.
final void	smoothScrollTo(int x, int y, int scrollDurationMs)	Like scrollTo(int, int), but scroll smoothly instead of immediately.

Methods inherited from class icyllis.modernui.widget.FrameLayout

checkLayoutParams, generateDefaultLayoutParams, generateLayoutParams, getMeasureAllChildren, setForegroundGravity, setMeasureAllChildren

Methods inherited from class icyllis.modernui.view.ViewGroup

addFocusables, addKeyboardNavigationClusters, addStatesFromChildren, addTouchables, addTransientView, addView, addViewInLayout, addViewInLayout, attachViewToParent, bringChildToFront, childDrawableStateChanged, childHasTransientStateChanged, cleanupLayoutState, clearChildFocus, clearDisappearingChildren, clearFocus, detachAllViewsFromParent, detachViewFromParent, detachViewFromParent, detachViewsFromParent, dispatchDraw, dispatchDrawableHotspotChanged, dispatchFinishTemporaryDetach, dispatchGenericPointerEvent, dispatchHoverEvent, dispatchKeyShortcutEvent, dispatchSetActivated, dispatchSetPressed, dispatchSetSelected, dispatchStartTemporaryDetach, dispatchTouchEvent, dispatchVisibilityChanged, dispatchWindowFocusChanged, dispatchWindowVisibilityChanged, drawableStateChanged, drawChild, endViewTransition, findFocus, focusableViewAvailable, focusSearch, getChildAt, getChildCount, getChildDrawingOrder, getChildDrawingOrder, getChildMeasureSpec, getChildVisibleRect, getChildVisibleRect, getClipChildren, getClipToPadding, getDescendantFocusability, getFocusedChild, getLayoutTransition, getNestedScrollAxes, getTouchscreenBlocksFocus, getTransientView, getTransientViewCount, getTransientViewIndex, hasBooleanFlag, hasFocus, hasTransientState, indexOfChild, internalSetPadding, invalidateChild, invalidateChildInParent, isChildrenDrawingOrderEnabled, isLayoutSuppressed, isTransitionGroup, jumpDrawablesToCurrentState, layout, measureChildren, offsetChildrenTopAndBottom, offsetDescendantRectToMyCoords, offsetRectIntoDescendantCoords, onChildVisibilityChanged, onCreateDrawableState, onInterceptHoverEvent, onNestedPreFling, onNestedPreScroll, onResolvePointerIcon, onSetLayoutParams, onStopNestedScroll, onViewAdded, onViewRemoved, removeAllViews, removeAllViewsInLayout, removeDetachedView, removeTransientView, removeView, removeViewAt, removeViewInLayout, removeViews, removeViewsInLayout, requestFocus, requestTransitionStart, resetResolvedDrawables, resolveDrawables, resolveLayoutDirection, resolveLayoutParams, resolvePadding, resolveRtlPropertiesIfNeeded, resolveTextAlignment, resolveTextDirection, restoreDefaultFocus, setAddStatesFromChildren, setBooleanFlag, setChildrenDrawingOrderEnabled, setClipChildren, setClipToPadding, setDescendantFocusability, setLayoutTransition, setShadowAlpha, setTouchscreenBlocksFocus, setTransitionGroup, showContextMenuForChild, startActionModeForChild, startViewTransition, suppressLayout, transformPointToViewLocal, updateViewLayout

Methods inherited from class icyllis.modernui.view.View

addFocusables, addOnAttachStateChangeListener, addOnLayoutChangeListener, awakenScrollBars, awakenScrollBars, callOnClick, cancelLongPress, cancelPendingInputEvents, canReceivePointerEvents, canResolveLayoutDirection, canResolveTextAlignment, canResolveTextDirection, canScrollHorizontally, canScrollVertically, combineMeasuredStates, createContextMenu, dispatchGenericMotionEvent, dispatchNestedFling, dispatchNestedPreFling, dispatchNestedPreScroll, dispatchNestedScroll, dispatchPointerEvent, dp, draw, drawableHotspotChanged, findViewById, findViewByPredicate, findViewByPredicateInsideOut, findViewWithTag, focusSearch, forceHasOverlappingRendering, forceLayout, generateViewId, getAlpha, getAnimationMatrix, getBackground, getBaseline, getBottom, getBoundsOnScreen, getBoundsOnScreen, getClipBounds, getClipBounds, getContentDescription, getContext, getContextMenuInfo, getDefaultSize, getDrawableState, getDrawingRect, getElevation, getFadingEdge, getFadingEdgeLength, getFocusable, getFocusables, getFocusedRect, getForeground, getForegroundGravity, getGlobalVisibleRect, getGlobalVisibleRect, getHandler, getHasOverlappingRendering, getHeight, getHitRect, getHorizontalScrollbarHeight, getHorizontalScrollbarThumbDrawable, getHorizontalScrollbarTrackDrawable, getId, getInverseMatrix, getKeyDispatcherState, getLayoutDirection, getLayoutParams, getLeft, getLocalVisibleRect, getLocationInWindow, getLocationOnScreen, getMatrix, getMeasuredHeight, getMeasuredHeightAndState, getMeasuredState, getMeasuredWidth, getMeasuredWidthAndState, getMinimumHeight, getMinimumWidth, getNextClusterForwardId, getNextFocusDownId, getNextFocusForwardId, getNextFocusLeftId, getNextFocusRightId, getNextFocusUpId, getOnFocusChangeListener, getOnLongClickListener, getOutlineProvider, getOverScrollMode, getPaddingBottom, getPaddingEnd, getPaddingLeft, getPaddingRight, getPaddingStart, getPaddingTop, getParent, getPivotX, getPivotY, getRawLayoutDirection, getRawTextAlignment, getRawTextDirection, getRevealOnFocusHint, getRight, getRootView, getRotation, getRotationX, getRotationY, getScaleX, getScaleY, getScrollBarDefaultDelayBeforeFade, getScrollBarFadeDuration, getScrollBarSize, getScrollBarStyle, getScrollIndicators, getScrollX, getScrollY, getStateDescription, getStateListAnimator, getSuggestedMinimumHeight, getSuggestedMinimumWidth, getTag, getTag, getTextAlignment, getTextDirection, getTooltipText, getTooltipView, getTop, getTouchables, getTransitionAlpha, getTransitionName, getTranslationX, getTranslationY, getTranslationZ, getVerticalFadingEdgeLength, getVerticalScrollbarThumbDrawable, getVerticalScrollbarTrackDrawable, getVerticalScrollbarWidth, getViewRoot, getViewTreeObserver, getVisibility, getWidth, getWindowAttachCount, getWindowVisibility, getX, getY, getZ, handleScrollBarDragging, hasExplicitFocusable, hasFocusable, hasIdentityMatrix, hasNestedScrollingParent, hasOnClickListeners, hasOnLongClickListeners, hasOverlappingRendering, hasTranslationTransientState, hasWindowFocus, invalidate, invalidate, invalidate, invalidateDrawable, invalidateOutline, isActivated, isAttachedToWindow, isClickable, isContextClickable, isDuplicateParentStateEnabled, isEnabled, isFocusable, isFocusableInTouchMode, isFocused, isFocusedByDefault, isForegroundInsidePadding, isHapticFeedbackEnabled, isHorizontalFadingEdgeEnabled, isHorizontalScrollBarEnabled, isHovered, isInLayout, isInScrollingContainer, isInTouchMode, isKeyboardNavigationCluster, isLaidOut, isLayoutDirectionInherited, isLayoutDirectionResolved, isLayoutRequested, isLayoutRtl, isLongClickable, isNestedScrollingEnabled, isPaddingRelative, isPivotSet, isPressed, isRootNamespace, isScrollbarFadingEnabled, isSelected, isShowingLayoutBounds, isShown, isSoundEffectsEnabled, isTemporarilyDetached, isTextAlignmentInherited, isTextAlignmentResolved, isTextDirectionInherited, isTextDirectionResolved, isVerticalFadingEdgeEnabled, isVerticalScrollBarEnabled, isVerticalScrollBarHidden, keyboardNavigationClusterSearch, mapRectFromViewToScreenCoords, measure, mergeDrawableStates, offsetLeftAndRight, offsetTopAndBottom, onCancelPendingInputEvents, onCreateContextMenu, onDetachedFromWindow, onDragEvent, onDraw, onDrawScrollBars, onFinishTemporaryDetach, onFocusChanged, onHoverChanged, onHoverEvent, onKeyDown, onKeyShortcut, onKeyUp, onResolveDrawables, onRtlPropertiesChanged, onStartTemporaryDetach, onVisibilityAggregated, onVisibilityChanged, onWindowFocusChanged, onWindowVisibilityChanged, overScrollBy, performButtonActionOnTouchDown, performClick, performContextClick, performContextClick, performHapticFeedback, performHapticFeedback, performLongClick, performLongClick, playSoundEffect, pointInView, post, postDelayed, postInvalidate, postInvalidateDelayed, postInvalidateOnAnimation, postOnAnimation, postOnAnimationDelayed, refreshDrawableState, removeCallbacks, removeOnAttachStateChangeListener, removeOnLayoutChangeListener, requestFocus, requestFocus, requestRectangleOnScreen, requestRectangleOnScreen, requireViewById, resetPivot, resolveSize, resolveSizeAndState, scheduleDrawable, scrollBy, setActivated, setAlpha, setAnimationMatrix, setBackground, setBottom, setClickable, setClipBounds, setContentDescription, setContextClickable, setDuplicateParentStateEnabled, setElevation, setEnabled, setFocusable, setFocusable, setFocusableInTouchMode, setFocusedByDefault, setFocusedInCluster, setForeground, setFrame, setHapticFeedbackEnabled, setHasTransientState, setHasTranslationTransientState, setHorizontalFadingEdgeEnabled, setHorizontalScrollBarEnabled, setHorizontalScrollbarThumbDrawable, setHorizontalScrollbarTrackDrawable, setHovered, setId, setIsRootNamespace, setKeyboardNavigationCluster, setLayoutDirection, setLayoutParams, setLeft, setLongClickable, setMeasuredDimension, setMinimumHeight, setMinimumWidth, setNestedScrollingEnabled, setNextClusterForwardId, setNextFocusDownId, setNextFocusForwardId, setNextFocusLeftId, setNextFocusRightId, setNextFocusUpId, setOnClickListener, setOnContextClickListener, setOnCreateContextMenuListener, setOnDragListener, setOnFocusChangeListener, setOnGenericMotionListener, setOnHoverListener, setOnKeyListener, setOnLongClickListener, setOnScrollChangeListener, setOnTouchListener, setOutlineProvider, setOverScrollMode, setPadding, setPaddingRelative, setPivotX, setPivotY, setPressed, setRevealOnFocusHint, setRight, setRotation, setRotationX, setRotationY, setScaleX, setScaleY, setScrollBarDefaultDelayBeforeFade, setScrollBarFadeDuration, setScrollbarFadingEnabled, setScrollBarSize, setScrollBarStyle, setScrollIndicators, setScrollIndicators, setScrollX, setScrollY, setSelected, setSoundEffectsEnabled, setStateDescription, setStateListAnimator, setTag, setTag, setTextAlignment, setTextDirection, setTooltipText, setTop, setTransitionAlpha, setTransitionName, setTransitionVisibility, setTranslationX, setTranslationY, setTranslationZ, setVerticalFadingEdgeEnabled, setVerticalScrollBarEnabled, setVerticalScrollbarThumbDrawable, setVerticalScrollbarTrackDrawable, setVisibility, setWillNotDraw, setX, setY, setZ, showContextMenu, showContextMenu, sp, startActionMode, startActionMode, startDragAndDrop, startNestedScroll, stopNestedScroll, toGlobalMotionEvent, toLocalMotionEvent, toString, transformFromViewToWindowSpace, transformMatrixToGlobal, transformMatrixToLocal, unscheduleDrawable, unscheduleDrawable, verifyDrawable, willNotDraw

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface icyllis.modernui.view.ViewParent

canResolveLayoutDirection, canResolveTextAlignment, canResolveTextDirection, createContextMenu, getLayoutDirection, getParent, getTextAlignment, getTextDirection, isLayoutDirectionResolved, isLayoutRequested, isTextAlignmentResolved, isTextDirectionResolved, keyboardNavigationClusterSearch

Constructor Details

NestedScrollView

public NestedScrollView(Context context)

Method Details

onStartNestedScroll

public boolean onStartNestedScroll(@NonNull
 View child,
 @NonNull
 View target,
 int axes,
 int type)

Description copied from interface: ViewParent

React to a descendant view initiating a nestable scroll operation, claiming the nested scroll operation if appropriate.

This method will be called in response to a descendant view invoking View.startNestedScroll(int, int). Each parent up the view hierarchy will be given an opportunity to respond and claim the nested scrolling operation by returning true.

This method may be overridden by ViewParent implementations to indicate when the view is willing to support a nested scrolling operation that is about to begin. If it returns true, this ViewParent will become the target view's nested scrolling parent for the duration of the scroll operation in progress. When the nested scroll is finished this ViewParent will receive a call to ViewParent.onStopNestedScroll(View, int).

Specified by:

onStartNestedScroll in interface ViewParent

Overrides:

onStartNestedScroll in class ViewGroup

Parameters:

child - Direct child of this ViewParent containing target

target - View that initiated the nested scroll

axes - Flags consisting of View.SCROLL_AXIS_HORIZONTAL, View.SCROLL_AXIS_VERTICAL or both

type - the type of input which cause this scroll event

Returns:

true if this ViewParent accepts the nested scroll operation

onNestedScrollAccepted

public void onNestedScrollAccepted(@NonNull
 View child,
 @NonNull
 View target,
 int axes,
 int type)

Description copied from interface: ViewParent

React to the successful claiming of a nested scroll operation.

This method will be called after onStartNestedScroll returns true. It offers an opportunity for the view and its superclasses to perform initial configuration for the nested scroll. Implementations of this method should always call their superclasses' implementation of this method if one is present.

Specified by:

onNestedScrollAccepted in interface ViewParent

Overrides:

onNestedScrollAccepted in class ViewGroup

Parameters:

child - Direct child of this ViewParent containing target

target - View that initiated the nested scroll

axes - Flags consisting of View.SCROLL_AXIS_HORIZONTAL, View.SCROLL_AXIS_VERTICAL or both

type - the type of input which cause this scroll event

See Also:

• ViewParent.onStartNestedScroll(View, View, int, int)
• ViewParent.onStopNestedScroll(View, int)

onNestedScroll

public void onNestedScroll(@NonNull
 View target,
 int dxConsumed,
 int dyConsumed,
 int dxUnconsumed,
 int dyUnconsumed,
 int type,
 @NonNull
 int[] consumed)

Description copied from interface: ViewParent

React to a nested scroll in progress.

This method will be called when the ViewParent's current nested scrolling child view dispatches a nested scroll event. To receive calls to this method the ViewParent must have previously returned true for a call to ViewParent.onStartNestedScroll(View, View, int, int).

Both the consumed and unconsumed portions of the scroll distance are reported to the ViewParent. An implementation may choose to use the consumed portion to match or chase scroll position of multiple child elements, for example. The unconsumed portion may be used to allow continuous dragging of multiple scrolling or draggable elements, such as scrolling a list within a vertical drawer where the drawer begins dragging once the edge of inner scrolling content is reached.

This method is called when a nested scrolling child invokes View.dispatchNestedScroll(int, int, int, int, int[], int, int[])} or one of methods it overloads.

An implementation must report how many pixels of the x and y scroll distances were consumed by this nested scrolling parent by adding the consumed distances to the consumed parameter. consumed should also be passed up to it's nested scrolling parent so that the parent may also add any scroll distance it consumes. Index 0 corresponds to dx and index 1 corresponds to dy.

Specified by:

onNestedScroll in interface ViewParent

Overrides:

onNestedScroll in class ViewGroup

Parameters:

target - The descendant view controlling the nested scroll

dxConsumed - Horizontal scroll distance in pixels already consumed by target

dyConsumed - Vertical scroll distance in pixels already consumed by target

dxUnconsumed - Horizontal scroll distance in pixels not consumed by target

dyUnconsumed - Vertical scroll distance in pixels not consumed by target

type - the type of input which cause this scroll event

consumed - Output. Upon this method returning, will contain the scroll distances consumed by this nested scrolling parent and the scroll distances consumed by any other parent up the view hierarchy

See Also:

• View.dispatchNestedScroll(int, int, int, int, int[], int, int[])

onNestedFling

public boolean onNestedFling(@NonNull
 View target,
 float velocityX,
 float velocityY,
 boolean consumed)

Description copied from interface: ViewParent

Request a fling from a nested scroll.

This method signifies that a nested scrolling child has detected suitable conditions for a fling. Generally this means that a touch scroll has ended with a velocity in the direction of scrolling that meets or exceeds the minimum fling velocity along a scrollable axis.

If a nested scrolling child view would normally fling but it is at the edge of its own content, it can use this method to delegate the fling to its nested scrolling parent instead. The parent may optionally consume the fling or observe a child fling.

Specified by:

onNestedFling in interface ViewParent

Overrides:

onNestedFling in class ViewGroup

Parameters:

target - View that initiated the nested scroll

velocityX - Horizontal velocity in pixels per second

velocityY - Vertical velocity in pixels per second

consumed - true if the child consumed the fling, false otherwise

Returns:

true if this parent consumed or otherwise reacted to the fling

shouldDelayChildPressedState

public boolean shouldDelayChildPressedState()

Description copied from class: ViewGroup

Return true if the pressed state should be delayed for children or descendants of this ViewGroup. Generally, this should be done for containers that can scroll, such as a List. This prevents the pressed state from appearing when the user is actually trying to scroll the content.

The default implementation returns false. Subclasses that do scroll should override this method and return true.

Overrides:

shouldDelayChildPressedState in class ViewGroup

getMaxScrollAmount

public int getMaxScrollAmount()

Returns:

The maximum amount this scroll view will scroll in response to an arrow event.

addView

public void addView(@NonNull
 View child)

Description copied from class: ViewGroup

Adds a child view. If no layout parameters are already set on the child, the default parameters for this ViewGroup are set on the child.

Note: do not invoke this method from View.draw(Canvas), View.onDraw(Canvas), ViewGroup.dispatchDraw(Canvas) or any related method.

Overrides:

addView in class ViewGroup

Parameters:

child - the child view to add

See Also:

• ViewGroup.generateDefaultLayoutParams()

addView

public void addView(@NonNull
 View child,
 int index)

Description copied from class: ViewGroup

Adds a child view. If no layout parameters are already set on the child, the default parameters for this ViewGroup are set on the child.

Note: do not invoke this method from View.draw(Canvas), View.onDraw(Canvas), ViewGroup.dispatchDraw(Canvas) or any related method.

Overrides:

addView in class ViewGroup

Parameters:

child - the child view to add

index - the position at which to add the child

See Also:

• ViewGroup.generateDefaultLayoutParams()

addView

public void addView(@NonNull
 View child,
 @NonNull
 ViewGroup.LayoutParams params)

Description copied from class: ViewGroup

Adds a child view with the specified layout parameters.

Note: do not invoke this method from View.draw(Canvas), View.onDraw(Canvas), ViewGroup.dispatchDraw(Canvas) or any related method.

Specified by:

addView in interface ViewManager

Overrides:

addView in class ViewGroup

Parameters:

child - the child view to add

params - the layout parameters to set on the child

addView

public void addView(@NonNull
 View child,
 int index,
 @NonNull
 ViewGroup.LayoutParams params)

Description copied from class: ViewGroup

Adds a child view with the specified layout parameters.

Note: do not invoke this method from View.draw(Canvas), View.onDraw(Canvas), ViewGroup.dispatchDraw(Canvas) or any related method.

Overrides:

addView in class ViewGroup

Parameters:

child - the child view to add

index - the position at which to add the child or -1 to add last

params - the layout parameters to set on the child

setOnScrollChangeListener

public void setOnScrollChangeListener(@Nullable
 NestedScrollView.OnScrollChangeListener l)

Register a callback to be invoked when the scroll X or Y positions of this view change.

This version of the method works on all versions of Android, back to API v4.

Parameters:

l - The listener to notify when the scroll X or Y position changes.

See Also:

• View.getScrollX()
• View.getScrollY()

isFillViewport

public boolean isFillViewport()

Indicates whether this ScrollView's content is stretched to fill the viewport.

Returns:

True if the content fills the viewport, false otherwise.

setFillViewport

public void setFillViewport(boolean fillViewport)

Set whether this ScrollView should stretch its content height to fill the viewport or not.

Parameters:

fillViewport - True to stretch the content's height to the viewport's boundaries, false otherwise.

isSmoothScrollingEnabled

public boolean isSmoothScrollingEnabled()

Returns:

Whether arrow scrolling will animate its transition.

setSmoothScrollingEnabled

public void setSmoothScrollingEnabled(boolean smoothScrollingEnabled)

Set whether arrow scrolling will animate its transition.

Parameters:

smoothScrollingEnabled - whether arrow scrolling will animate its transition

onScrollChanged

protected void onScrollChanged(int l,
 int t,
 int oldl,
 int oldt)

Description copied from class: View

This is called in response to an internal scroll in this view (i.e., the view scrolled its own contents). This is typically as a result of View.scrollBy(int, int) or View.scrollTo(int, int) having been called.

Overrides:

onScrollChanged in class View

Parameters:

l - Current horizontal scroll origin.

t - Current vertical scroll origin.

oldl - Previous horizontal scroll origin.

oldt - Previous vertical scroll origin.

onMeasure

protected void onMeasure(int widthMeasureSpec,
 int heightMeasureSpec)

Description copied from class: View

Measure the view and its content to determine the measured width and the measured height. This method is invoked by View.measure(int, int) and should be overridden by subclasses to provide accurate and efficient measurement of their contents.

CONTRACT: When overriding this method, you must call View.setMeasuredDimension(int, int) to store the measured width and height of this view. Failure to do so will trigger an IllegalStateException, thrown by View.measure(int, int). Calling super.onMeasure() is a valid use.

The base class implementation of measure defaults to the background size, unless a larger size is allowed by the MeasureSpec. Subclasses should override the base one to provide better measurements of their content.

Overrides:

onMeasure in class FrameLayout

Parameters:

widthMeasureSpec - width measure specification imposed by the parent MeasureSpec

heightMeasureSpec - height measure specification imposed by the parent MeasureSpec

dispatchKeyEvent

public boolean dispatchKeyEvent(@NonNull
 KeyEvent event)

Description copied from class: View

Dispatch a key event to the next view on the focus path. This path runs from the top of the view tree down to the currently focused view. If this view has focus, it will dispatch to itself. Otherwise it will dispatch the next node down the focus path. This method also fires any key listeners.

Overrides:

dispatchKeyEvent in class ViewGroup

Parameters:

event - The key event to be dispatched.

Returns:

True if the event was handled, false otherwise.

executeKeyEvent

public boolean executeKeyEvent(@NonNull
 KeyEvent event)

You can call this function yourself to have the scroll view perform scrolling from a key event, just as if the event had been dispatched to it by the view hierarchy.

Parameters:

event - The key event to execute.

Returns:

Return true if the event was handled, else false.

requestDisallowInterceptTouchEvent

public void requestDisallowInterceptTouchEvent(boolean disallowIntercept)

Description copied from interface: ViewParent

Called when a child does not want this parent and its ancestors to intercept touch events with ViewGroup.onInterceptTouchEvent(MotionEvent).

This parent should pass this call onto its parents. This parent must obey this request for the duration of the touch (that is, only clear the flag after this parent has received an up or a cancel.

Specified by:

requestDisallowInterceptTouchEvent in interface ViewParent

Overrides:

requestDisallowInterceptTouchEvent in class ViewGroup

Parameters:

disallowIntercept - True if the child does not want the parent to intercept touch events.

onInterceptTouchEvent

public boolean onInterceptTouchEvent(@NonNull
 MotionEvent ev)

Description copied from class: ViewGroup

Implement this method to intercept all touch screen motion events. This allows you to watch events as they are dispatched to your children, and take ownership of the current gesture at any point.

Using this function takes some care, as it has a fairly complicated interaction with View.onTouchEvent(MotionEvent), and using it requires implementing that method as well as this one in the correct way. Events will be received in the following order:

1. You will receive the down event here.
2. The down event will be handled either by a child of this view group, or given to your own onTouchEvent() method to handle; this means you should implement onTouchEvent() to return true, so you will continue to see the rest of the gesture (instead of looking for a parent view to handle it). Also, by returning true from onTouchEvent(), you will not receive any following events in onInterceptTouchEvent() and all touch processing must happen in onTouchEvent() like normal.
3. For as long as you return false from this function, each following event (up to and including the final up) will be delivered first here and then to the target's onTouchEvent().
4. If you return true from here, you will not receive any following events: the target view will receive the same event but with the action MotionEvent.ACTION_CANCEL, and all further events will be delivered to your onTouchEvent() method and no longer appear here.

Overrides:

onInterceptTouchEvent in class ViewGroup

Parameters:

ev - The motion event being dispatched down the hierarchy.

Returns:

Return true to steal motion events from the children and have them dispatched to this ViewGroup through onTouchEvent(). The current target will receive an ACTION_CANCEL event, and no further messages will be delivered here.

onTouchEvent

public boolean onTouchEvent(@NonNull
 MotionEvent ev)

Description copied from class: View

Implement this method to handle touch screen motion events.

If this method is used to detect click actions, it is recommended that the actions be performed by implementing and calling View.performClick(). This will ensure consistent system behavior.

Overrides:

onTouchEvent in class View

Parameters:

ev - the touch event

Returns:

true if the event was handled by the view, false otherwise

onGenericMotionEvent

public boolean onGenericMotionEvent(@NonNull
 MotionEvent event)

Description copied from class: View

Implement this method to handle generic motion events.

Implementations of this method should check if this view ENABLED and CLICKABLE.

Overrides:

onGenericMotionEvent in class View

Parameters:

event - the generic motion event being processed.

Returns:

true if the event was consumed by the view, false otherwise

onOverScrolled

protected void onOverScrolled(int scrollX,
 int scrollY,
 boolean clampedX,
 boolean clampedY)

Description copied from class: View

Called by View.overScrollBy(int, int, int, int, int, int, int, int, boolean) to respond to the results of an over-scroll operation.

Overrides:

onOverScrolled in class View

Parameters:

scrollX - New X scroll value in pixels

scrollY - New Y scroll value in pixels

clampedX - True if scrollX was clamped to an over-scroll boundary

clampedY - True if scrollY was clamped to an over-scroll boundary

pageScroll

public boolean pageScroll(int direction)

Handles scrolling in response to a "page up/down" shortcut press. This method will scroll the view by one page up or down and give the focus to the topmost/bottommost component in the new visible area. If no component is a good candidate for focus, this scrollview reclaims the focus.

Parameters:

direction - the scroll direction: View.FOCUS_UP to go one page up or View.FOCUS_DOWN to go one page down

Returns:

true if the key event is consumed by this method, false otherwise

fullScroll

public boolean fullScroll(int direction)

Handles scrolling in response to a "home/end" shortcut press. This method will scroll the view to the top or bottom and give the focus to the topmost/bottommost component in the new visible area. If no component is a good candidate for focus, this scrollview reclaims the focus.

Parameters:

direction - the scroll direction: View.FOCUS_UP to go the top of the view or View.FOCUS_DOWN to go the bottom

Returns:

true if the key event is consumed by this method, false otherwise

arrowScroll

public boolean arrowScroll(int direction)

Handle scrolling in response to an up or down arrow click.

Parameters:

direction - The direction corresponding to the arrow key that was pressed

Returns:

True if we consumed the event, false otherwise

smoothScrollBy

public final void smoothScrollBy(int dx,
 int dy)

Like View.scrollBy(int, int), but scroll smoothly instead of immediately.

Parameters:

dx - the number of pixels to scroll by on the X axis

dy - the number of pixels to scroll by on the Y axis

smoothScrollBy

public final void smoothScrollBy(int dx,
 int dy,
 int scrollDurationMs)

Like View.scrollBy(int, int), but scroll smoothly instead of immediately.

Parameters:

dx - the number of pixels to scroll by on the X axis

dy - the number of pixels to scroll by on the Y axis

scrollDurationMs - the duration of the smooth scroll operation in milliseconds

smoothScrollTo

public final void smoothScrollTo(int x,
 int y)

Like scrollTo(int, int), but scroll smoothly instead of immediately.

Parameters:

x - the position where to scroll on the X axis

y - the position where to scroll on the Y axis

smoothScrollTo

public final void smoothScrollTo(int x,
 int y,
 int scrollDurationMs)

Like scrollTo(int, int), but scroll smoothly instead of immediately.

Parameters:

x - the position where to scroll on the X axis

y - the position where to scroll on the Y axis

scrollDurationMs - the duration of the smooth scroll operation in milliseconds

computeVerticalScrollRange

public int computeVerticalScrollRange()

The scroll range of a scroll view is the overall height of all of its children.

Overrides:

computeVerticalScrollRange in class View

Returns:

the total vertical range represented by the vertical scrollbar

The default range is the drawing height of this view.

See Also:

• View.computeVerticalScrollExtent()
• View.computeVerticalScrollOffset()

computeVerticalScrollOffset

public int computeVerticalScrollOffset()

Description copied from class: View

Compute the vertical offset of the vertical scrollbar's thumb within the horizontal range. This value is used to compute the position of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by View.computeVerticalScrollRange() and View.computeVerticalScrollExtent().

The default offset is the scroll offset of this view.

Overrides:

computeVerticalScrollOffset in class View

Returns:

the vertical offset of the scrollbar's thumb

See Also:

• View.computeVerticalScrollRange()
• View.computeVerticalScrollExtent()

computeVerticalScrollExtent

public int computeVerticalScrollExtent()

Description copied from class: View

Compute the vertical extent of the vertical scrollbar's thumb within the vertical range. This value is used to compute the length of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by View.computeVerticalScrollRange() and View.computeVerticalScrollOffset().

The default extent is the drawing height of this view.

Overrides:

computeVerticalScrollExtent in class View

Returns:

the vertical extent of the scrollbar's thumb

See Also:

• View.computeVerticalScrollRange()
• View.computeVerticalScrollOffset()

computeHorizontalScrollRange

public int computeHorizontalScrollRange()

Description copied from class: View

Compute the horizontal range that the horizontal scrollbar represents.

The range is expressed in arbitrary units that must be the same as the units used by View.computeHorizontalScrollExtent() and View.computeHorizontalScrollOffset().

The default range is the drawing width of this view.

Overrides:

computeHorizontalScrollRange in class View

Returns:

the total horizontal range represented by the horizontal scrollbar

See Also:

• View.computeHorizontalScrollExtent()
• View.computeHorizontalScrollOffset()

computeHorizontalScrollOffset

public int computeHorizontalScrollOffset()

Description copied from class: View

Compute the horizontal offset of the horizontal scrollbar's thumb within the horizontal range. This value is used to compute the position of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by View.computeHorizontalScrollRange() and View.computeHorizontalScrollExtent().

The default offset is the scroll offset of this view.

Overrides:

computeHorizontalScrollOffset in class View

Returns:

the horizontal offset of the scrollbar's thumb

See Also:

• View.computeHorizontalScrollRange()
• View.computeHorizontalScrollExtent()

computeHorizontalScrollExtent

public int computeHorizontalScrollExtent()

Description copied from class: View

Compute the horizontal extent of the horizontal scrollbar's thumb within the horizontal range. This value is used to compute the length of the thumb within the scrollbar's track.

The range is expressed in arbitrary units that must be the same as the units used by View.computeHorizontalScrollRange() and View.computeHorizontalScrollOffset().

The default extent is the drawing width of this view.

Overrides:

computeHorizontalScrollExtent in class View

Returns:

the horizontal extent of the scrollbar's thumb

See Also:

• View.computeHorizontalScrollRange()
• View.computeHorizontalScrollOffset()

measureChild

protected void measureChild(@NonNull
 View child,
 int parentWidthMeasureSpec,
 int parentHeightMeasureSpec)

Description copied from class: ViewGroup

Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding. The heavy lifting is done in getChildMeasureSpec.

Overrides:

measureChild in class ViewGroup

Parameters:

child - The child to measure

parentWidthMeasureSpec - The width requirements for this view

parentHeightMeasureSpec - The height requirements for this view

measureChildWithMargins

protected void measureChildWithMargins(@NonNull
 View child,
 int parentWidthMeasureSpec,
 int widthUsed,
 int parentHeightMeasureSpec,
 int heightUsed)

Description copied from class: ViewGroup

Ask one of the children of this view to measure itself, taking into account both the MeasureSpec requirements for this view and its padding and margins. The child must have MarginLayoutParams The heavy lifting is done in getChildMeasureSpec.

Overrides:

measureChildWithMargins in class ViewGroup

Parameters:

child - The child to measure

parentWidthMeasureSpec - The width requirements for this view

widthUsed - Extra space that has been used up by the parent horizontally (possibly by other children of the parent)

parentHeightMeasureSpec - The height requirements for this view

heightUsed - Extra space that has been used up by the parent vertically (possibly by other children of the parent)

computeScroll

public void computeScroll()

Description copied from class: View

Called by a parent to request that a child update its values for mScrollX and mScrollY if necessary. This will typically be done if the child is animating a scroll using a Scroller.

Overrides:

computeScroll in class View

computeScrollDeltaToGetChildRectOnScreen

protected int computeScrollDeltaToGetChildRectOnScreen(Rect rect)

Compute the amount to scroll in the Y direction in order to get a rectangle completely on the screen (or, if taller than the screen, at least the first screen size chunk of it).

Parameters:

rect - The rect.

Returns:

The scroll delta.

requestChildFocus

public void requestChildFocus(View child,
 View focused)

Description copied from interface: ViewParent

Called when a child of this parent wants focus

Specified by:

requestChildFocus in interface ViewParent

Overrides:

requestChildFocus in class ViewGroup

Parameters:

child - The child of this ViewParent that wants focus. This view will contain the focused view. It is not necessarily the view that actually has focus.

focused - The view that is a descendant of child that actually has focus

onRequestFocusInDescendants

protected boolean onRequestFocusInDescendants(int direction,
 Rect previouslyFocusedRect)

When looking for focus in children of a scroll view, need to be a little more careful not to give focus to something that is scrolled off screen.

This is more expensive than the default ViewGroup implementation, otherwise this behavior might have been made the default.

Overrides:

onRequestFocusInDescendants in class ViewGroup

Parameters:

direction - One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT

previouslyFocusedRect - The rectangle (in this View's coordinate system) to give a finer grained hint about where focus is coming from. May be null if there is no hint.

Returns:

Whether focus was taken.

requestChildRectangleOnScreen

public boolean requestChildRectangleOnScreen(View child,
 Rect rectangle,
 boolean immediate)

Description copied from interface: ViewParent

Called when a child of this group wants a particular rectangle to be positioned onto the screen. ViewGroups overriding this can trust that:

• child will be a direct child of this group
• rectangle will be in the child's content coordinates

ViewGroups overriding this should uphold the contract:

• nothing will change if the rectangle is already visible
• the view port will be scrolled only just enough to make the rectangle visible

Specified by:

requestChildRectangleOnScreen in interface ViewParent

Overrides:

requestChildRectangleOnScreen in class ViewGroup

Parameters:

child - The direct child making the request.

rectangle - The rectangle in the child's coordinates the child wishes to be on the screen.

immediate - True to forbid animated or delayed scrolling, false otherwise

Returns:

Whether the group scrolled to handle the operation

requestLayout

public void requestLayout()

Description copied from class: View

Call this when something has changed which has invalidated the layout of this view. This will schedule a layout pass of the view tree. This should not be called while the view hierarchy is currently in a layout pass (View.isInLayout(). If layout is happening, the request may be honored at the end of the current layout pass (and then layout will run again) or after the current frame is drawn and the next layout occurs.

Subclasses which override this method should call the superclass method to handle possible request-during-layout errors correctly.

Specified by:

requestLayout in interface ViewParent

Overrides:

requestLayout in class View

onLayout

protected void onLayout(boolean changed,
 int l,
 int t,
 int r,
 int b)

Description copied from class: View

Called from View.layout(int, int, int, int) when this view should assign a size and position to each of its children.

Derived classes with children should override this method and call layout on each of their children.

Overrides:

onLayout in class FrameLayout

Parameters:

changed - This is a new size or position for this view

l - Left position, relative to parent

t - Top position, relative to parent

r - Right position, relative to parent

b - Bottom position, relative to parent

onAttachedToWindow

public void onAttachedToWindow()

Description copied from class: View

This is called when the view is attached to a window. At this point it has a Surface and will start drawing. Note that this function is guaranteed to be called before View.onDraw(Canvas), however it may be called any time before the first onDraw -- including before or after View.onMeasure(int, int).

Overrides:

onAttachedToWindow in class View

See Also:

• View.onDetachedFromWindow()

onSizeChanged

protected void onSizeChanged(int w,
 int h,
 int oldw,
 int oldh)

Description copied from class: View

Called when width or height changed

Overrides:

onSizeChanged in class View

Parameters:

w - new width

h - new height

oldw - previous width

oldh - previous height

fling

public void fling(int velocityY)

Fling the scroll view

Parameters:

velocityY - The initial velocity in the Y direction. Positive numbers mean that the finger/cursor is moving down the screen, which means we want to scroll towards the top.

scrollTo

public void scrollTo(int x,
 int y)

Set the scrolled position of your view. This will cause a call to View.onScrollChanged(int, int, int, int) and the view will be invalidated.

This version also clamps the scrolling to the bounds of our child.

Overrides:

scrollTo in class View

Parameters:

x - the x position to scroll to

y - the y position to scroll to

onDrawForeground

public void onDrawForeground(@NonNull
 Canvas canvas)

Description copied from class: View

Draw any foreground content for this view.

Foreground content may consist of scroll bars, a foreground drawable or other view-specific decorations. The foreground is drawn on top of the primary view content.

Overrides:

onDrawForeground in class View

Parameters:

canvas - the canvas to draw content