| /* |
| * Copyright (C) 2006 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package android.view; |
| |
| import android.graphics.Rect; |
| import android.view.accessibility.AccessibilityEvent; |
| |
| /** |
| * Defines the responsibilities for a class that will be a parent of a View. |
| * This is the API that a view sees when it wants to interact with its parent. |
| * |
| */ |
| public interface ViewParent { |
| /** |
| * Called when something has changed which has invalidated the layout of a |
| * child of this view parent. This will schedule a layout pass of the view |
| * tree. |
| */ |
| public void requestLayout(); |
| |
| /** |
| * Indicates whether layout was requested on this view parent. |
| * |
| * @return true if layout was requested, false otherwise |
| */ |
| public boolean isLayoutRequested(); |
| |
| /** |
| * Called when a child wants the view hierarchy to gather and report |
| * transparent regions to the window compositor. Views that "punch" holes in |
| * the view hierarchy, such as SurfaceView can use this API to improve |
| * performance of the system. When no such a view is present in the |
| * hierarchy, this optimization in unnecessary and might slightly reduce the |
| * view hierarchy performance. |
| * |
| * @param child the view requesting the transparent region computation |
| * |
| */ |
| public void requestTransparentRegion(View child); |
| |
| /** |
| * All or part of a child is dirty and needs to be redrawn. |
| * |
| * @param child The child which is dirty |
| * @param r The area within the child that is invalid |
| */ |
| public void invalidateChild(View child, Rect r); |
| |
| /** |
| * All or part of a child is dirty and needs to be redrawn. |
| * |
| * <p>The location array is an array of two int values which respectively |
| * define the left and the top position of the dirty child.</p> |
| * |
| * <p>This method must return the parent of this ViewParent if the specified |
| * rectangle must be invalidated in the parent. If the specified rectangle |
| * does not require invalidation in the parent or if the parent does not |
| * exist, this method must return null.</p> |
| * |
| * <p>When this method returns a non-null value, the location array must |
| * have been updated with the left and top coordinates of this ViewParent.</p> |
| * |
| * @param location An array of 2 ints containing the left and top |
| * coordinates of the child to invalidate |
| * @param r The area within the child that is invalid |
| * |
| * @return the parent of this ViewParent or null |
| */ |
| public ViewParent invalidateChildInParent(int[] location, Rect r); |
| |
| /** |
| * Returns the parent if it exists, or null. |
| * |
| * @return a ViewParent or null if this ViewParent does not have a parent |
| */ |
| public ViewParent getParent(); |
| |
| /** |
| * Called when a child of this parent wants focus |
| * |
| * @param 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. |
| * @param focused The view that is a descendant of child that actually has |
| * focus |
| */ |
| public void requestChildFocus(View child, View focused); |
| |
| /** |
| * Tell view hierarchy that the global view attributes need to be |
| * re-evaluated. |
| * |
| * @param child View whose attributes have changed. |
| */ |
| public void recomputeViewAttributes(View child); |
| |
| /** |
| * Called when a child of this parent is giving up focus |
| * |
| * @param child The view that is giving up focus |
| */ |
| public void clearChildFocus(View child); |
| |
| /** |
| * Compute the visible part of a rectangular region defined in terms of a child view's |
| * coordinates. |
| * |
| * <p>Returns the clipped visible part of the rectangle <code>r</code>, defined in the |
| * <code>child</code>'s local coordinate system. <code>r</code> is modified by this method to |
| * contain the result, expressed in the global (root) coordinate system.</p> |
| * |
| * <p>The resulting rectangle is always axis aligned. If a rotation is applied to a node in the |
| * View hierarchy, the result is the axis-aligned bounding box of the visible rectangle.</p> |
| * |
| * @param child A child View, whose rectangular visible region we want to compute |
| * @param r The input rectangle, defined in the child coordinate system. Will be overwritten to |
| * contain the resulting visible rectangle, expressed in global (root) coordinates |
| * @param offset The input coordinates of a point, defined in the child coordinate system. |
| * As with the <code>r</code> parameter, this will be overwritten to contain the global (root) |
| * coordinates of that point. |
| * A <code>null</code> value is valid (in case you are not interested in this result) |
| * @return true if the resulting rectangle is not empty, false otherwise |
| */ |
| public boolean getChildVisibleRect(View child, Rect r, android.graphics.Point offset); |
| |
| /** |
| * Find the nearest view in the specified direction that wants to take focus |
| * |
| * @param v The view that currently has focus |
| * @param direction One of FOCUS_UP, FOCUS_DOWN, FOCUS_LEFT, and FOCUS_RIGHT |
| */ |
| public View focusSearch(View v, int direction); |
| |
| /** |
| * Change the z order of the child so it's on top of all other children |
| * |
| * @param child |
| */ |
| public void bringChildToFront(View child); |
| |
| /** |
| * Tells the parent that a new focusable view has become available. This is |
| * to handle transitions from the case where there are no focusable views to |
| * the case where the first focusable view appears. |
| * |
| * @param v The view that has become newly focusable |
| */ |
| public void focusableViewAvailable(View v); |
| |
| /** |
| * Bring up a context menu for the specified view or its ancestors. |
| * |
| * <p>In most cases, a subclass does not need to override this. However, if |
| * the subclass is added directly to the window manager (for example, |
| * {@link ViewManager#addView(View, android.view.ViewGroup.LayoutParams)}) |
| * then it should override this and show the context menu.</p> |
| * |
| * @param originalView The source view where the context menu was first invoked |
| * @return true if a context menu was displayed |
| */ |
| public boolean showContextMenuForChild(View originalView); |
| |
| /** |
| * Have the parent populate the specified context menu if it has anything to |
| * add (and then recurse on its parent). |
| * |
| * @param menu The menu to populate |
| */ |
| public void createContextMenu(ContextMenu menu); |
| |
| /** |
| * Start an action mode for the specified view. |
| * |
| * <p>In most cases, a subclass does not need to override this. However, if the |
| * subclass is added directly to the window manager (for example, |
| * {@link ViewManager#addView(View, android.view.ViewGroup.LayoutParams)}) |
| * then it should override this and start the action mode.</p> |
| * |
| * @param originalView The source view where the action mode was first invoked |
| * @param callback The callback that will handle lifecycle events for the action mode |
| * @return The new action mode if it was started, null otherwise |
| */ |
| public ActionMode startActionModeForChild(View originalView, ActionMode.Callback callback); |
| |
| /** |
| * This method is called on the parent when a child's drawable state |
| * has changed. |
| * |
| * @param child The child whose drawable state has changed. |
| */ |
| public void childDrawableStateChanged(View child); |
| |
| /** |
| * Called when a child does not want this parent and its ancestors to |
| * intercept touch events with |
| * {@link ViewGroup#onInterceptTouchEvent(MotionEvent)}. |
| * |
| * <p>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.</p> |
| * |
| * @param disallowIntercept True if the child does not want the parent to |
| * intercept touch events. |
| */ |
| public void requestDisallowInterceptTouchEvent(boolean disallowIntercept); |
| |
| /** |
| * Called when a child of this group wants a particular rectangle to be |
| * positioned onto the screen. {@link ViewGroup}s overriding this can trust |
| * that: |
| * <ul> |
| * <li>child will be a direct child of this group</li> |
| * <li>rectangle will be in the child's coordinates</li> |
| * </ul> |
| * |
| * <p>{@link ViewGroup}s overriding this should uphold the contract:</p> |
| * <ul> |
| * <li>nothing will change if the rectangle is already visible</li> |
| * <li>the view port will be scrolled only just enough to make the |
| * rectangle visible</li> |
| * <ul> |
| * |
| * @param child The direct child making the request. |
| * @param rectangle The rectangle in the child's coordinates the child |
| * wishes to be on the screen. |
| * @param immediate True to forbid animated or delayed scrolling, |
| * false otherwise |
| * @return Whether the group scrolled to handle the operation |
| */ |
| public boolean requestChildRectangleOnScreen(View child, Rect rectangle, |
| boolean immediate); |
| |
| /** |
| * Called by a child to request from its parent to send an {@link AccessibilityEvent}. |
| * The child has already populated a record for itself in the event and is delegating |
| * to its parent to send the event. The parent can optionally add a record for itself. |
| * <p> |
| * Note: An accessibility event is fired by an individual view which populates the |
| * event with a record for its state and requests from its parent to perform |
| * the sending. The parent can optionally add a record for itself before |
| * dispatching the request to its parent. A parent can also choose not to |
| * respect the request for sending the event. The accessibility event is sent |
| * by the topmost view in the view tree.</p> |
| * |
| * @param child The child which requests sending the event. |
| * @param event The event to be sent. |
| * @return True if the event was sent. |
| */ |
| public boolean requestSendAccessibilityEvent(View child, AccessibilityEvent event); |
| |
| /** |
| * Called when a child view now has or no longer is tracking transient state. |
| * |
| * @param child Child view whose state has changed |
| * @param hasTransientState true if this child has transient state |
| * |
| * @hide |
| */ |
| public void childHasTransientStateChanged(View child, boolean hasTransientState); |
| |
| /** |
| * Ask that a new dispatch of {@link View#fitSystemWindows(Rect) |
| * View.fitSystemWindows(Rect)} be performed. |
| */ |
| public void requestFitSystemWindows(); |
| |
| /** |
| * Gets the parent of a given View for accessibility. Since some Views are not |
| * exposed to the accessibility layer the parent for accessibility is not |
| * necessarily the direct parent of the View, rather it is a predecessor. |
| * |
| * @return The parent or <code>null</code> if no such is found. |
| */ |
| public ViewParent getParentForAccessibility(); |
| |
| /** |
| * A child notifies its parent that its state for accessibility has changed. |
| * That is some of the child properties reported to accessibility services has |
| * changed, hence the interested services have to be notified for the new state. |
| * |
| * @hide |
| */ |
| public void childAccessibilityStateChanged(View child); |
| } |