invalidate
invalidate() ->
invalidateInternal ->
p.invalidateChild(this, damage); (p = mParent;)
/*
* Caller is responsible for calling requestLayout if necessary.
* (This allows addViewInLayout to not request a new layout.)
*/
@UnsupportedAppUsage
void assignParent(ViewParent parent) {
if (mParent == null) {
mParent = parent;
} else if (parent == null) {
mParent = null;
} else {
throw new RuntimeException("view " + this + " being added, but"
+ " it already has a parent");
}
}
/**
* Invalidate the whole view. If the view is visible,
* {@link #onDraw(android.graphics.Canvas)} will be called at some point in
* the future.
* <p>
* This must be called from a UI thread. To call from a non-UI thread, call
* {@link #postInvalidate()}.
*/
public void invalidate() {
invalidate(true);
}
/**
* This is where the invalidate() work actually happens. A full invalidate()
* causes the drawing cache to be invalidated, but this function can be
* called with invalidateCache set to false to skip that invalidation step
* for cases that do not need it (for example, a component that remains at
* the same dimensions with the same content).
*
* @param invalidateCache Whether the drawing cache for this view should be
* invalidated as well. This is usually true for a full
* invalidate, but may be set to false if the View's contents or
* dimensions have not changed.
* @hide
*/
@UnsupportedAppUsage
public void invalidate(boolean invalidateCache) {
invalidateInternal(0, 0, mRight - mLeft, mBottom - mTop, invalidateCache, true);
}
void invalidateInternal(int l, int t, int r, int b, boolean invalidateCache,
boolean fullInvalidate) {
if (mGhostView != null) {
mGhostView.invalidate(true);
return;
}
if (skipInvalidate()) {
return;
}
// Reset content capture caches
mPrivateFlags4 &= ~PFLAG4_CONTENT_CAPTURE_IMPORTANCE_MASK;
mContentCaptureSessionCached = false;
if ((mPrivateFlags & (PFLAG_DRAWN | PFLAG_HAS_BOUNDS)) == (PFLAG_DRAWN | PFLAG_HAS_BOUNDS)
|| (invalidateCache && (mPrivateFlags & PFLAG_DRAWING_CACHE_VALID) == PFLAG_DRAWING_CACHE_VALID)
|| (mPrivateFlags & PFLAG_INVALIDATED) != PFLAG_INVALIDATED
|| (fullInvalidate && isOpaque() != mLastIsOpaque)) {
if (fullInvalidate) {
mLastIsOpaque = isOpaque();
mPrivateFlags &= ~PFLAG_DRAWN;
}
mPrivateFlags |= PFLAG_DIRTY;
if (invalidateCache) {
mPrivateFlags |= PFLAG_INVALIDATED;
mPrivateFlags &= ~PFLAG_DRAWING_CACHE_VALID;
}
// Propagate the damage rectangle to the parent view.
final AttachInfo ai = mAttachInfo;
final ViewParent p = mParent;
if (p != null && ai != null && l < r && t < b) {
final Rect damage = ai.mTmpInvalRect;
damage.set(l, t, r, b);
p.invalidateChild(this, damage);
}
// Damage the entire projection receiver, if necessary.
if (mBackground != null && mBackground.isProjected()) {
final View receiver = getProjectionReceiver();
if (receiver != null) {
receiver.damageInParent();
}
}
}
}
ViewRootImpl.invalidateChild
invalidateChild ->
invalidateChildInParent ->
invalidateRectOnScreen ->
scheduleTraversals
最后调用到 scheduleTraversals() 方法
@Override
public void invalidateChild(View child, Rect dirty) {
invalidateChildInParent(null, dirty);
}
@Override
public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
checkThread();
if (DEBUG_DRAW) Log.v(mTag, "Invalidate child: " + dirty);
if (dirty == null) {
invalidate();
return null;
} else if (dirty.isEmpty() && !mIsAnimating) {
return null;
}
if (mCurScrollY != 0 || mTranslator != null) {
mTempRect.set(dirty);
dirty = mTempRect;
if (mCurScrollY != 0) {
dirty.offset(0, -mCurScrollY);
}
if (mTranslator != null) {
mTranslator.translateRectInAppWindowToScreen(dirty);
}
if (mAttachInfo.mScalingRequired) {
dirty.inset(-1, -1);
}
}
invalidateRectOnScreen(dirty);
return null;
}
private void invalidateRectOnScreen(Rect dirty) {
final Rect localDirty = mDirty;
// Add the new dirty rect to the current one
localDirty.union(dirty.left, dirty.top, dirty.right, dirty.bottom);
// Intersect with the bounds of the window to skip
// updates that lie outside of the visible region
final float appScale = mAttachInfo.mApplicationScale;
final boolean intersected = localDirty.intersect(0, 0,
(int) (mWidth * appScale + 0.5f), (int) (mHeight * appScale + 0.5f));
if (!intersected) {
localDirty.setEmpty();
}
if (!mWillDrawSoon && (intersected || mIsAnimating)) {
scheduleTraversals();
}
}
scheduleTraversals ->
在下边
doTraversal ->
final class TraversalRunnable implements Runnable {
@Override
public void run() {
doTraversal();
}
}
final TraversalRunnable mTraversalRunnable = new TraversalRunnable();
@UnsupportedAppUsage
void scheduleTraversals() {
if (!mTraversalScheduled) {
mTraversalScheduled = true;
//post 消息屏障到队列中, 这里会在住线程 loop 中判断屏障
mTraversalBarrier = mHandler.getLooper().getQueue().postSyncBarrier();
//post runnable, 有特殊标记, 会先于其他类型的 msg 执行
mChoreographer.postCallback(
Choreographer.CALLBACK_TRAVERSAL, mTraversalRunnable, null);
notifyRendererOfFramePending();
pokeDrawLockIfNeeded();
}
}
void doTraversal() {
if (mTraversalScheduled) {
mTraversalScheduled = false;
mHandler.getLooper().getQueue().removeSyncBarrier(mTraversalBarrier);
if (mProfile) {
Debug.startMethodTracing("ViewAncestor");
}
performTraversals();
if (mProfile) {
Debug.stopMethodTracing();
mProfile = false;
}
}
}
performTraversals ->
执行遍历
private void performTraversals() {
// cache mView since it is used so much below...
...
mIsInTraversal = true;
mWillDrawSoon = true;
boolean windowSizeMayChange = false;
WindowManager.LayoutParams lp = mWindowAttributes;
int desiredWindowWidth;
int desiredWindowHeight;
final int viewVisibility = getHostVisibility();
final boolean viewVisibilityChanged = !mFirst
&& (mViewVisibility != viewVisibility || mNewSurfaceNeeded
// Also check for possible double visibility update, which will make current
// viewVisibility value equal to mViewVisibility and we may miss it.
|| mAppVisibilityChanged);
mAppVisibilityChanged = false;
final boolean viewUserVisibilityChanged = !mFirst &&
((mViewVisibility == View.VISIBLE) != (viewVisibility == View.VISIBLE));
WindowManager.LayoutParams params = null;
CompatibilityInfo compatibilityInfo =
mDisplay.getDisplayAdjustments().getCompatibilityInfo();
if (compatibilityInfo.supportsScreen() == mLastInCompatMode) {
params = lp;
mFullRedrawNeeded = true;
mLayoutRequested = true;
if (mLastInCompatMode) {
params.privateFlags &= ~WindowManager.LayoutParams.PRIVATE_FLAG_COMPATIBLE_WINDOW;
mLastInCompatMode = false;
} else {
params.privateFlags |= WindowManager.LayoutParams.PRIVATE_FLAG_COMPATIBLE_WINDOW;
mLastInCompatMode = true;
}
}
Rect frame = mWinFrame;
if (mFirst) {
mFullRedrawNeeded = true;
mLayoutRequested = true;
final Configuration config = mContext.getResources().getConfiguration();
if (shouldUseDisplaySize(lp)) {
// NOTE -- system code, won't try to do compat mode.
Point size = new Point();
mDisplay.getRealSize(size);
desiredWindowWidth = size.x;
desiredWindowHeight = size.y;
} else if (lp.width == ViewGroup.LayoutParams.WRAP_CONTENT
|| lp.height == ViewGroup.LayoutParams.WRAP_CONTENT) {
// For wrap content, we have to remeasure later on anyways. Use size consistent with
// below so we get best use of the measure cache.
desiredWindowWidth = dipToPx(config.screenWidthDp);
desiredWindowHeight = dipToPx(config.screenHeightDp);
} else {
// After addToDisplay, the frame contains the frameHint from window manager, which
// for most windows is going to be the same size as the result of relayoutWindow.
// Using this here allows us to avoid remeasuring after relayoutWindow
desiredWindowWidth = frame.width();
desiredWindowHeight = frame.height();
}
// We used to use the following condition to choose 32 bits drawing caches:
// PixelFormat.hasAlpha(lp.format) || lp.format == PixelFormat.RGBX_8888
// However, windows are now always 32 bits by default, so choose 32 bits
mAttachInfo.mUse32BitDrawingCache = true;
mAttachInfo.mWindowVisibility = viewVisibility;
mAttachInfo.mRecomputeGlobalAttributes = false;
mLastConfigurationFromResources.setTo(config);
mLastSystemUiVisibility = mAttachInfo.mSystemUiVisibility;
// Set the layout direction if it has not been set before (inherit is the default)
if (mViewLayoutDirectionInitial == View.LAYOUT_DIRECTION_INHERIT) {
host.setLayoutDirection(config.getLayoutDirection());
}
host.dispatchAttachedToWindow(mAttachInfo, 0);
mAttachInfo.mTreeObserver.dispatchOnWindowAttachedChange(true);
dispatchApplyInsets(host);
} else {
desiredWindowWidth = frame.width();
desiredWindowHeight = frame.height();
if (desiredWindowWidth != mWidth || desiredWindowHeight != mHeight) {
if (DEBUG_ORIENTATION) Log.v(mTag, "View " + host + " resized to: " + frame);
mFullRedrawNeeded = true;
mLayoutRequested = true;
windowSizeMayChange = true;
}
}
if (viewVisibilityChanged) {
mAttachInfo.mWindowVisibility = viewVisibility;
host.dispatchWindowVisibilityChanged(viewVisibility);
if (viewUserVisibilityChanged) {
host.dispatchVisibilityAggregated(viewVisibility == View.VISIBLE);
}
if (viewVisibility != View.VISIBLE || mNewSurfaceNeeded) {
endDragResizing();
destroyHardwareResources();
}
}
// Non-visible windows can't hold accessibility focus.
if (mAttachInfo.mWindowVisibility != View.VISIBLE) {
host.clearAccessibilityFocus();
}
// Execute enqueued actions on every traversal in case a detached view enqueued an action
getRunQueue().executeActions(mAttachInfo.mHandler);
boolean cutoutChanged = false;
boolean layoutRequested = mLayoutRequested && (!mStopped || mReportNextDraw);
if (layoutRequested) {
final Resources res = mView.getContext().getResources();
if (mFirst) {
// make sure touch mode code executes by setting cached value
// to opposite of the added touch mode.
mAttachInfo.mInTouchMode = !mAddedTouchMode;
ensureTouchModeLocally(mAddedTouchMode);
} else {
if (!mPendingDisplayCutout.equals(mAttachInfo.mDisplayCutout)) {
cutoutChanged = true;
}
if (lp.width == ViewGroup.LayoutParams.WRAP_CONTENT
|| lp.height == ViewGroup.LayoutParams.WRAP_CONTENT) {
windowSizeMayChange = true;
if (shouldUseDisplaySize(lp)) {
// NOTE -- system code, won't try to do compat mode.
Point size = new Point();
mDisplay.getRealSize(size);
desiredWindowWidth = size.x;
desiredWindowHeight = size.y;
} else {
Configuration config = res.getConfiguration();
desiredWindowWidth = dipToPx(config.screenWidthDp);
desiredWindowHeight = dipToPx(config.screenHeightDp);
}
}
}
// Ask host how big it wants to be
windowSizeMayChange |= measureHierarchy(host, lp, res,
desiredWindowWidth, desiredWindowHeight);
}
if (collectViewAttributes()) {
params = lp;
}
if (mAttachInfo.mForceReportNewAttributes) {
mAttachInfo.mForceReportNewAttributes = false;
params = lp;
}
if (mFirst || mAttachInfo.mViewVisibilityChanged) {
mAttachInfo.mViewVisibilityChanged = false;
int resizeMode = mSoftInputMode &
WindowManager.LayoutParams.SOFT_INPUT_MASK_ADJUST;
// If we are in auto resize mode, then we need to determine
// what mode to use now.
if (resizeMode == WindowManager.LayoutParams.SOFT_INPUT_ADJUST_UNSPECIFIED) {
final int N = mAttachInfo.mScrollContainers.size();
for (int i=0; i<N; i++) {
if (mAttachInfo.mScrollContainers.get(i).isShown()) {
resizeMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE;
}
}
if (resizeMode == 0) {
resizeMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_PAN;
}
if ((lp.softInputMode &
WindowManager.LayoutParams.SOFT_INPUT_MASK_ADJUST) != resizeMode) {
lp.softInputMode = (lp.softInputMode &
~WindowManager.LayoutParams.SOFT_INPUT_MASK_ADJUST) |
resizeMode;
params = lp;
}
}
}
if (mApplyInsetsRequested) {
dispatchApplyInsets(host);
if (mLayoutRequested) {
// Short-circuit catching a new layout request here, so
// we don't need to go through two layout passes when things
// change due to fitting system windows, which can happen a lot.
windowSizeMayChange |= measureHierarchy(host, lp,
mView.getContext().getResources(),
desiredWindowWidth, desiredWindowHeight);
}
}
if (layoutRequested) {
// Clear this now, so that if anything requests a layout in the
// rest of this function we will catch it and re-run a full
// layout pass.
mLayoutRequested = false;
}
boolean windowShouldResize = layoutRequested && windowSizeMayChange
&& ((mWidth != host.getMeasuredWidth() || mHeight != host.getMeasuredHeight())
|| (lp.width == ViewGroup.LayoutParams.WRAP_CONTENT &&
frame.width() < desiredWindowWidth && frame.width() != mWidth)
|| (lp.height == ViewGroup.LayoutParams.WRAP_CONTENT &&
frame.height() < desiredWindowHeight && frame.height() != mHeight));
windowShouldResize |= mDragResizing && mResizeMode == RESIZE_MODE_FREEFORM;
// If the activity was just relaunched, it might have unfrozen the task bounds (while
// relaunching), so we need to force a call into window manager to pick up the latest
// bounds.
windowShouldResize |= mActivityRelaunched;
// Determine whether to compute insets.
// If there are no inset listeners remaining then we may still need to compute
// insets in case the old insets were non-empty and must be reset.
final boolean computesInternalInsets =
mAttachInfo.mTreeObserver.hasComputeInternalInsetsListeners()
|| mAttachInfo.mHasNonEmptyGivenInternalInsets;
boolean insetsPending = false;
int relayoutResult = 0;
boolean updatedConfiguration = false;
final int surfaceGenerationId = mSurface.getGenerationId();
final boolean isViewVisible = viewVisibility == View.VISIBLE;
final boolean windowRelayoutWasForced = mForceNextWindowRelayout;
boolean surfaceSizeChanged = false;
boolean surfaceCreated = false;
boolean surfaceDestroyed = false;
/* True if surface generation id changes. */
boolean surfaceReplaced = false;
final boolean windowAttributesChanged = mWindowAttributesChanged;
if (windowAttributesChanged) {
mWindowAttributesChanged = false;
params = lp;
}
if (params != null) {
if ((host.mPrivateFlags & View.PFLAG_REQUEST_TRANSPARENT_REGIONS) != 0
&& !PixelFormat.formatHasAlpha(params.format)) {
params.format = PixelFormat.TRANSLUCENT;
}
adjustLayoutParamsForCompatibility(params);
controlInsetsForCompatibility(params);
}
if (mFirst || windowShouldResize || viewVisibilityChanged || cutoutChanged || params != null
|| mForceNextWindowRelayout) {
mForceNextWindowRelayout = false;
if (isViewVisible) {
// If this window is giving internal insets to the window
// manager, and it is being added or changing its visibility,
// then we want to first give the window manager "fake"
// insets to cause it to effectively ignore the content of
// the window during layout. This avoids it briefly causing
// other windows to resize/move based on the raw frame of the
// window, waiting until we can finish laying out this window
// and get back to the window manager with the ultimately
// computed insets.
insetsPending = computesInternalInsets && (mFirst || viewVisibilityChanged);
}
if (mSurfaceHolder != null) {
mSurfaceHolder.mSurfaceLock.lock();
mDrawingAllowed = true;
}
boolean hwInitialized = false;
boolean dispatchApplyInsets = false;
boolean hadSurface = mSurface.isValid();
try {
if (DEBUG_LAYOUT) {
Log.i(mTag, "host=w:" + host.getMeasuredWidth() + ", h:" +
host.getMeasuredHeight() + ", params=" + params);
}
if (mAttachInfo.mThreadedRenderer != null) {
// relayoutWindow may decide to destroy mSurface. As that decision
// happens in WindowManager service, we need to be defensive here
// and stop using the surface in case it gets destroyed.
if (mAttachInfo.mThreadedRenderer.pause()) {
// Animations were running so we need to push a frame
// to resume them
mDirty.set(0, 0, mWidth, mHeight);
}
mChoreographer.mFrameInfo.addFlags(FrameInfo.FLAG_WINDOW_LAYOUT_CHANGED);
}
relayoutResult = relayoutWindow(params, viewVisibility, insetsPending);
if (DEBUG_LAYOUT) Log.v(mTag, "relayout: frame=" + frame.toShortString()
+ " cutout=" + mPendingDisplayCutout.get().toString()
+ " surface=" + mSurface);
// If the pending {@link MergedConfiguration} handed back from
// {@link #relayoutWindow} does not match the one last reported,
// WindowManagerService has reported back a frame from a configuration not yet
// handled by the client. In this case, we need to accept the configuration so we
// do not lay out and draw with the wrong configuration.
if (!mPendingMergedConfiguration.equals(mLastReportedMergedConfiguration)) {
if (DEBUG_CONFIGURATION) Log.v(mTag, "Visible with new config: "
+ mPendingMergedConfiguration.getMergedConfiguration());
performConfigurationChange(mPendingMergedConfiguration, !mFirst,
INVALID_DISPLAY /* same display */);
updatedConfiguration = true;
}
cutoutChanged = !mPendingDisplayCutout.equals(mAttachInfo.mDisplayCutout);
surfaceSizeChanged = (relayoutResult
& WindowManagerGlobal.RELAYOUT_RES_SURFACE_RESIZED) != 0;
final boolean alwaysConsumeSystemBarsChanged =
mPendingAlwaysConsumeSystemBars != mAttachInfo.mAlwaysConsumeSystemBars;
final boolean colorModeChanged = hasColorModeChanged(lp.getColorMode());
surfaceCreated = !hadSurface && mSurface.isValid();
surfaceDestroyed = hadSurface && !mSurface.isValid();
surfaceReplaced = (surfaceGenerationId != mSurface.getGenerationId())
&& mSurface.isValid();
if (cutoutChanged) {
mAttachInfo.mDisplayCutout.set(mPendingDisplayCutout);
if (DEBUG_LAYOUT) {
Log.v(mTag, "DisplayCutout changing to: " + mAttachInfo.mDisplayCutout);
}
// Need to relayout with content insets.
dispatchApplyInsets = true;
}
if (alwaysConsumeSystemBarsChanged) {
mAttachInfo.mAlwaysConsumeSystemBars = mPendingAlwaysConsumeSystemBars;
dispatchApplyInsets = true;
}
if (updateCaptionInsets()) {
dispatchApplyInsets = true;
}
if (dispatchApplyInsets || mLastSystemUiVisibility !=
mAttachInfo.mSystemUiVisibility || mApplyInsetsRequested) {
mLastSystemUiVisibility = mAttachInfo.mSystemUiVisibility;
dispatchApplyInsets(host);
// We applied insets so force contentInsetsChanged to ensure the
// hierarchy is measured below.
dispatchApplyInsets = true;
}
if (colorModeChanged && mAttachInfo.mThreadedRenderer != null) {
mAttachInfo.mThreadedRenderer.setWideGamut(
lp.getColorMode() == ActivityInfo.COLOR_MODE_WIDE_COLOR_GAMUT);
}
if (surfaceCreated) {
// If we are creating a new surface, then we need to
// completely redraw it.
mFullRedrawNeeded = true;
mPreviousTransparentRegion.setEmpty();
// Only initialize up-front if transparent regions are not
// requested, otherwise defer to see if the entire window
// will be transparent
if (mAttachInfo.mThreadedRenderer != null) {
try {
hwInitialized = mAttachInfo.mThreadedRenderer.initialize(mSurface);
if (hwInitialized && (host.mPrivateFlags
& View.PFLAG_REQUEST_TRANSPARENT_REGIONS) == 0) {
// Don't pre-allocate if transparent regions
// are requested as they may not be needed
mAttachInfo.mThreadedRenderer.allocateBuffers();
}
} catch (OutOfResourcesException e) {
handleOutOfResourcesException(e);
return;
}
}
notifySurfaceCreated();
} else if (surfaceDestroyed) {
// If the surface has been removed, then reset the scroll
// positions.
if (mLastScrolledFocus != null) {
mLastScrolledFocus.clear();
}
mScrollY = mCurScrollY = 0;
if (mView instanceof RootViewSurfaceTaker) {
((RootViewSurfaceTaker) mView).onRootViewScrollYChanged(mCurScrollY);
}
if (mScroller != null) {
mScroller.abortAnimation();
}
// Our surface is gone
if (mAttachInfo.mThreadedRenderer != null &&
mAttachInfo.mThreadedRenderer.isEnabled()) {
mAttachInfo.mThreadedRenderer.destroy();
}
} else if ((surfaceReplaced
|| surfaceSizeChanged || windowRelayoutWasForced || colorModeChanged)
&& mSurfaceHolder == null
&& mAttachInfo.mThreadedRenderer != null
&& mSurface.isValid()) {
mFullRedrawNeeded = true;
try {
// Need to do updateSurface (which leads to CanvasContext::setSurface and
// re-create the EGLSurface) if either the Surface changed (as indicated by
// generation id), or WindowManager changed the surface size. The latter is
// because on some chips, changing the consumer side's BufferQueue size may
// not take effect immediately unless we create a new EGLSurface.
// Note that frame size change doesn't always imply surface size change (eg.
// drag resizing uses fullscreen surface), need to check surfaceSizeChanged
// flag from WindowManager.
mAttachInfo.mThreadedRenderer.updateSurface(mSurface);
} catch (OutOfResourcesException e) {
handleOutOfResourcesException(e);
return;
}
}
if (!surfaceCreated && surfaceReplaced) {
notifySurfaceReplaced();
}
final boolean freeformResizing = (relayoutResult
& WindowManagerGlobal.RELAYOUT_RES_DRAG_RESIZING_FREEFORM) != 0;
final boolean dockedResizing = (relayoutResult
& WindowManagerGlobal.RELAYOUT_RES_DRAG_RESIZING_DOCKED) != 0;
final boolean dragResizing = freeformResizing || dockedResizing;
if (mDragResizing != dragResizing) {
if (dragResizing) {
mResizeMode = freeformResizing
? RESIZE_MODE_FREEFORM
: RESIZE_MODE_DOCKED_DIVIDER;
final boolean backdropSizeMatchesFrame =
mWinFrame.width() == mPendingBackDropFrame.width()
&& mWinFrame.height() == mPendingBackDropFrame.height();
// TODO: Need cutout?
startDragResizing(mPendingBackDropFrame, !backdropSizeMatchesFrame,
mLastWindowInsets.getSystemWindowInsets().toRect(),
mLastWindowInsets.getStableInsets().toRect(), mResizeMode);
} else {
// We shouldn't come here, but if we come we should end the resize.
endDragResizing();
}
}
if (!mUseMTRenderer) {
if (dragResizing) {
mCanvasOffsetX = mWinFrame.left;
mCanvasOffsetY = mWinFrame.top;
} else {
mCanvasOffsetX = mCanvasOffsetY = 0;
}
}
} catch (RemoteException e) {
}
if (DEBUG_ORIENTATION) Log.v(
TAG, "Relayout returned: frame=" + frame + ", surface=" + mSurface);
mAttachInfo.mWindowLeft = frame.left;
mAttachInfo.mWindowTop = frame.top;
// !!FIXME!! This next section handles the case where we did not get the
// window size we asked for. We should avoid this by getting a maximum size from
// the window session beforehand.
if (mWidth != frame.width() || mHeight != frame.height()) {
mWidth = frame.width();
mHeight = frame.height();
}
if (mSurfaceHolder != null) {
// The app owns the surface; tell it about what is going on.
if (mSurface.isValid()) {
// XXX .copyFrom() doesn't work!
//mSurfaceHolder.mSurface.copyFrom(mSurface);
mSurfaceHolder.mSurface = mSurface;
}
mSurfaceHolder.setSurfaceFrameSize(mWidth, mHeight);
mSurfaceHolder.mSurfaceLock.unlock();
if (surfaceCreated) {
mSurfaceHolder.ungetCallbacks();
mIsCreating = true;
SurfaceHolder.Callback[] callbacks = mSurfaceHolder.getCallbacks();
if (callbacks != null) {
for (SurfaceHolder.Callback c : callbacks) {
c.surfaceCreated(mSurfaceHolder);
}
}
}
if ((surfaceCreated || surfaceReplaced || surfaceSizeChanged
|| windowAttributesChanged) && mSurface.isValid()) {
SurfaceHolder.Callback[] callbacks = mSurfaceHolder.getCallbacks();
if (callbacks != null) {
for (SurfaceHolder.Callback c : callbacks) {
c.surfaceChanged(mSurfaceHolder, lp.format,
mWidth, mHeight);
}
}
mIsCreating = false;
}
if (surfaceDestroyed) {
notifyHolderSurfaceDestroyed();
mSurfaceHolder.mSurfaceLock.lock();
try {
mSurfaceHolder.mSurface = new Surface();
} finally {
mSurfaceHolder.mSurfaceLock.unlock();
}
}
}
final ThreadedRenderer threadedRenderer = mAttachInfo.mThreadedRenderer;
if (threadedRenderer != null && threadedRenderer.isEnabled()) {
if (hwInitialized
|| mWidth != threadedRenderer.getWidth()
|| mHeight != threadedRenderer.getHeight()
|| mNeedsRendererSetup) {
threadedRenderer.setup(mWidth, mHeight, mAttachInfo,
mWindowAttributes.surfaceInsets);
mNeedsRendererSetup = false;
}
}
if (!mStopped || mReportNextDraw) {
boolean focusChangedDueToTouchMode = ensureTouchModeLocally(
(relayoutResult&WindowManagerGlobal.RELAYOUT_RES_IN_TOUCH_MODE) != 0);
if (focusChangedDueToTouchMode || mWidth != host.getMeasuredWidth()
|| mHeight != host.getMeasuredHeight() || dispatchApplyInsets ||
updatedConfiguration) {
int childWidthMeasureSpec = getRootMeasureSpec(mWidth, lp.width);
int childHeightMeasureSpec = getRootMeasureSpec(mHeight, lp.height);
if (DEBUG_LAYOUT) Log.v(mTag, "Ooops, something changed! mWidth="
+ mWidth + " measuredWidth=" + host.getMeasuredWidth()
+ " mHeight=" + mHeight
+ " measuredHeight=" + host.getMeasuredHeight()
+ " dispatchApplyInsets=" + dispatchApplyInsets);
// Ask host how big it wants to be
performMeasure(childWidthMeasureSpec, childHeightMeasureSpec);
// Implementation of weights from WindowManager.LayoutParams
// We just grow the dimensions as needed and re-measure if
// needs be
int width = host.getMeasuredWidth();
int height = host.getMeasuredHeight();
boolean measureAgain = false;
if (lp.horizontalWeight > 0.0f) {
width += (int) ((mWidth - width) * lp.horizontalWeight);
childWidthMeasureSpec = MeasureSpec.makeMeasureSpec(width,
MeasureSpec.EXACTLY);
measureAgain = true;
}
if (lp.verticalWeight > 0.0f) {
height += (int) ((mHeight - height) * lp.verticalWeight);
childHeightMeasureSpec = MeasureSpec.makeMeasureSpec(height,
MeasureSpec.EXACTLY);
measureAgain = true;
}
if (measureAgain) {
if (DEBUG_LAYOUT) Log.v(mTag,
"And hey let's measure once more: width=" + width
+ " height=" + height);
performMeasure(childWidthMeasureSpec, childHeightMeasureSpec);
}
layoutRequested = true;
}
}
} else {
// Not the first pass and no window/insets/visibility change but the window
// may have moved and we need check that and if so to update the left and right
// in the attach info. We translate only the window frame since on window move
// the window manager tells us only for the new frame but the insets are the
// same and we do not want to translate them more than once.
maybeHandleWindowMove(frame);
}
if (surfaceSizeChanged || surfaceReplaced || surfaceCreated || windowAttributesChanged) {
// If the surface has been replaced, there's a chance the bounds layer is not parented
// to the new layer. When updating bounds layer, also reparent to the main VRI
// SurfaceControl to ensure it's correctly placed in the hierarchy.
//
// This needs to be done on the client side since WMS won't reparent the children to the
// new surface if it thinks the app is closing. WMS gets the signal that the app is
// stopping, but on the client side it doesn't get stopped since it's restarted quick
// enough. WMS doesn't want to keep around old children since they will leak when the
// client creates new children.
updateBoundsLayer(surfaceReplaced);
}
final boolean didLayout = layoutRequested && (!mStopped || mReportNextDraw);
boolean triggerGlobalLayoutListener = didLayout
|| mAttachInfo.mRecomputeGlobalAttributes;
if (didLayout) {
performLayout(lp, mWidth, mHeight);
// By this point all views have been sized and positioned
// We can compute the transparent area
if ((host.mPrivateFlags & View.PFLAG_REQUEST_TRANSPARENT_REGIONS) != 0) {
// start out transparent
// TODO: AVOID THAT CALL BY CACHING THE RESULT?
host.getLocationInWindow(mTmpLocation);
mTransparentRegion.set(mTmpLocation[0], mTmpLocation[1],
mTmpLocation[0] + host.mRight - host.mLeft,
mTmpLocation[1] + host.mBottom - host.mTop);
host.gatherTransparentRegion(mTransparentRegion);
if (mTranslator != null) {
mTranslator.translateRegionInWindowToScreen(mTransparentRegion);
}
if (!mTransparentRegion.equals(mPreviousTransparentRegion)) {
mPreviousTransparentRegion.set(mTransparentRegion);
mFullRedrawNeeded = true;
// reconfigure window manager
try {
mWindowSession.setTransparentRegion(mWindow, mTransparentRegion);
} catch (RemoteException e) {
}
}
}
if (DBG) {
System.out.println("======================================");
System.out.println("performTraversals -- after setFrame");
host.debug();
}
}
if (surfaceDestroyed) {
notifySurfaceDestroyed();
}
if (triggerGlobalLayoutListener) {
mAttachInfo.mRecomputeGlobalAttributes = false;
mAttachInfo.mTreeObserver.dispatchOnGlobalLayout();
}
if (computesInternalInsets) {
// Clear the original insets.
final ViewTreeObserver.InternalInsetsInfo insets = mAttachInfo.mGivenInternalInsets;
insets.reset();
// Compute new insets in place.
mAttachInfo.mTreeObserver.dispatchOnComputeInternalInsets(insets);
mAttachInfo.mHasNonEmptyGivenInternalInsets = !insets.isEmpty();
// Tell the window manager.
if (insetsPending || !mLastGivenInsets.equals(insets)) {
mLastGivenInsets.set(insets);
// Translate insets to screen coordinates if needed.
final Rect contentInsets;
final Rect visibleInsets;
final Region touchableRegion;
if (mTranslator != null) {
contentInsets = mTranslator.getTranslatedContentInsets(insets.contentInsets);
visibleInsets = mTranslator.getTranslatedVisibleInsets(insets.visibleInsets);
touchableRegion = mTranslator.getTranslatedTouchableArea(insets.touchableRegion);
} else {
contentInsets = insets.contentInsets;
visibleInsets = insets.visibleInsets;
touchableRegion = insets.touchableRegion;
}
try {
mWindowSession.setInsets(mWindow, insets.mTouchableInsets,
contentInsets, visibleInsets, touchableRegion);
} catch (RemoteException e) {
}
}
}
if (mFirst) {
if (sAlwaysAssignFocus || !isInTouchMode()) {
// handle first focus request
if (DEBUG_INPUT_RESIZE) {
Log.v(mTag, "First: mView.hasFocus()=" + mView.hasFocus());
}
if (mView != null) {
if (!mView.hasFocus()) {
mView.restoreDefaultFocus();
if (DEBUG_INPUT_RESIZE) {
Log.v(mTag, "First: requested focused view=" + mView.findFocus());
}
} else {
if (DEBUG_INPUT_RESIZE) {
Log.v(mTag, "First: existing focused view=" + mView.findFocus());
}
}
}
} else {
// Some views (like ScrollView) won't hand focus to descendants that aren't within
// their viewport. Before layout, there's a good change these views are size 0
// which means no children can get focus. After layout, this view now has size, but
// is not guaranteed to hand-off focus to a focusable child (specifically, the edge-
// case where the child has a size prior to layout and thus won't trigger
// focusableViewAvailable).
View focused = mView.findFocus();
if (focused instanceof ViewGroup
&& ((ViewGroup) focused).getDescendantFocusability()
== ViewGroup.FOCUS_AFTER_DESCENDANTS) {
focused.restoreDefaultFocus();
}
}
}
final boolean changedVisibility = (viewVisibilityChanged || mFirst) && isViewVisible;
final boolean hasWindowFocus = mAttachInfo.mHasWindowFocus && isViewVisible;
final boolean regainedFocus = hasWindowFocus && mLostWindowFocus;
if (regainedFocus) {
mLostWindowFocus = false;
} else if (!hasWindowFocus && mHadWindowFocus) {
mLostWindowFocus = true;
}
if (changedVisibility || regainedFocus) {
// Toasts are presented as notifications - don't present them as windows as well
boolean isToast = (mWindowAttributes == null) ? false
: (mWindowAttributes.type == TYPE_TOAST);
if (!isToast) {
host.sendAccessibilityEvent(AccessibilityEvent.TYPE_WINDOW_STATE_CHANGED);
}
}
mFirst = false;
mWillDrawSoon = false;
mNewSurfaceNeeded = false;
mActivityRelaunched = false;
mViewVisibility = viewVisibility;
mHadWindowFocus = hasWindowFocus;
mImeFocusController.onTraversal(hasWindowFocus, mWindowAttributes);
// Remember if we must report the next draw.
if ((relayoutResult & WindowManagerGlobal.RELAYOUT_RES_FIRST_TIME) != 0) {
reportNextDraw();
}
if ((relayoutResult & WindowManagerGlobal.RELAYOUT_RES_BLAST_SYNC) != 0) {
reportNextDraw();
setUseBLASTSyncTransaction();
mSendNextFrameToWm = true;
}
boolean cancelDraw = mAttachInfo.mTreeObserver.dispatchOnPreDraw() || !isViewVisible;
if (!cancelDraw) {
if (mPendingTransitions != null && mPendingTransitions.size() > 0) {
for (int i = 0; i < mPendingTransitions.size(); ++i) {
mPendingTransitions.get(i).startChangingAnimations();
}
mPendingTransitions.clear();
}
performDraw();
} else {
if (isViewVisible) {
// Try again
scheduleTraversals();
} else if (mPendingTransitions != null && mPendingTransitions.size() > 0) {
for (int i = 0; i < mPendingTransitions.size(); ++i) {
mPendingTransitions.get(i).endChangingAnimations();
}
mPendingTransitions.clear();
}
}
if (mAttachInfo.mContentCaptureEvents != null) {
notifyContentCatpureEvents();
}
mIsInTraversal = false;
}
performMeasure()
首先就是performMeasure的过程，这个方法会调用到View类的 measure 方法，这里并没有具体的测量实现，而是调用到了 onMeasure，需要子类去实现；
要知道 DecorView 其实就是个FrameLayout，是一个 ViewGroup，重写 onMeasure 方法，去循环遍历子 View 的 measure 过程；
根据自己的 MeasureSpec 和子View的 LayoutParams 来决定子 View 的测量规格，根据获得的测量规格得到子view 的宽高，然后一层一层向下遍历，子类也会重写 onMeasure 方法，测量自己的大小
performLayout()
这样所有的View测量结束，第二步就是 performLayout 了，默认是调用到了View类 layout 方法；
如果是ViewGroup，就调用ViewGroup的layout方法，但是这个方法没有具体实现，还是调用到了View类的layout方法；
View类的layout方法回调onLayout方法，要怎么确定位置由子类重写onlayout方法实现；这里DecorView去重写，自己实现，循环调用每个子View的layout方法，将上下左右坐标值传递给子View，确定子View的位置
performDraw()
接下来就是最后的绘制过程了，也就是第三步 performDraw，继续走到 ViewTreeObserver 的 dispatchOnDraw 方法，通知所有注册了 OnDrawListener 接口的View去调用自己的onDraw()方法，绘制自己；
DecorView 因为是个 ViewGroup，重写了 dispatchDraw 方法，循环调用每个子View的draw方法；最后就是每个子View重写onDraw方法绘制自身
总结 invalidate()：
view 的 invalidate 会导致当前view被重绘,
由于mLayoutRequested为false，不会导致 onMeasure 和 onLayout 被调用，而 OnDraw 会被调用
回顾一下 invalidate 的过程
- 给所有需要重新绘制的试图添加一个 DIRTY 或者 DIRTY_OPAQUE 标记
- 通过矩形运算, 找到真正需要重绘的矩形区, 并将保存在 ViewRooImpl 的 mDirty 变量中 , 有了这两个信息, View Tree 重新就能够决定通知那些 View 进行重绘, 并告诉他们重绘区域的大小.
