DecorView如何添加到Window上
需要了解DecorView如何添加到Window，需要了解Activity的启动过程，Activity的启动过程是
通过ActivityThread来调用的 。期间会调用，sendMessage发给H handler
ActivityThread:handleMessage-LAUNCH_ACTIVITY
ActivityThread:handleLaunchActivity 在该方法里面实例化window、windowMager和decorView，
并将deccorView添加到windowManager, 通过ViewRootImpl发起View的绘制流程。
通过performTraversals的方法执行U遍历绘制流程，执行过程会执行performMeasure() 、performLayout、performDraw
并依次调用View提供外部调用的public方法 Measure() ,Layout() 、Draw()
ActivityThread:performLaunchActivity
Instrumentation:callActivityOnCreate
Activity:performCreate
Activity:onCreate
源码代码：
ActivityThread.java
public void handleMessage(Message msg) {
if (DEBUG_MESSAGES) Slog.v(TAG, ">>> handling: " + codeToString(msg.what));
switch (msg.what) {
case LAUNCH_ACTIVITY: {//判断是启动Acitvity
Trace.traceBegin(Trace.TRACE_TAG_ACTIVITY_MANAGER, "activityStart");
final ActivityClientRecord r = (ActivityClientRecord) msg.obj;
r.packageInfo = getPackageInfoNoCheck(
r.activityInfo.applicationInfo, r.compatInfo);
handleLaunchActivity(r, null); //调用handleLaunchActivity方法
Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);
} break;
handleLaunchActivity方法:
private void handleLaunchActivity(ActivityClientRecord r, Intent customIntent) {
// If we are getting ready to gc after going to the background, well
// we are back active so skip it.
unscheduleGcIdler();
mSomeActivitiesChanged = true;
if (r.profilerInfo != null) {
mProfiler.setProfiler(r.profilerInfo);
mProfiler.startProfiling();
}
// Make sure we are running with the most recent config.
handleConfigurationChanged(null, null);
if (localLOGV) Slog.v(
TAG, "Handling launch of " + r);
// Initialize before creating the activity
WindowManagerGlobal.initialize();
Activity a = performLaunchActivity(r, customIntent);//调用performLaunchActivity方法
if (a != null) {
r.createdConfig = new Configuration(mConfiguration);
Bundle oldState = r.state;
//调用handleResumeActivity
handleResumeActivity(r.token, false, r.isForward,
!r.activity.mFinished && !r.startsNotResumed);
if (!r.activity.mFinished && r.startsNotResumed) {
// The activity manager actually wants this one to start out
// paused, because it needs to be visible but isn't in the
// foreground. We accomplish this by going through the
// normal startup (because activities expect to go through
// onResume() the first time they run, before their window
// is displayed), and then pausing it. However, in this case
// we do -not- need to do the full pause cycle (of freezing
// and such) because the activity manager assumes it can just
// retain the current state it has.
try {
r.activity.mCalled = false;
mInstrumentation.callActivityOnPause(r.activity);
// We need to keep around the original state, in case
// we need to be created again. But we only do this
// for pre-Honeycomb apps, which always save their state
// when pausing, so we can not have them save their state
// when restarting from a paused state. For HC and later,
// we want to (and can) let the state be saved as the normal
// part of stopping the activity.
if (r.isPreHoneycomb()) {
r.state = oldState;
}
if (!r.activity.mCalled) {
throw new SuperNotCalledException(
"Activity " + r.intent.getComponent().toShortString() +
" did not call through to super.onPause()");
}
} catch (SuperNotCalledException e) {
throw e;
} catch (Exception e) {
if (!mInstrumentation.onException(r.activity, e)) {
throw new RuntimeException(
"Unable to pause activity "
+ r.intent.getComponent().toShortString()
+ ": " + e.toString(), e);
}
}
r.paused = true;
}
} else {
// If there was an error, for any reason, tell the activity
// manager to stop us.
try {
ActivityManagerNative.getDefault()
.finishActivity(r.token, Activity.RESULT_CANCELED, null, false);
} catch (RemoteException ex) {
// Ignore
}
}
}
handleResumeActivity方法：
final void handleResumeActivity(IBinder token,
boolean clearHide, boolean isForward, boolean reallyResume) {
// If we are getting ready to gc after going to the background, well
// we are back active so skip it.
unscheduleGcIdler();
mSomeActivitiesChanged = true;
// TODO Push resumeArgs into the activity for consideration
ActivityClientRecord r = performResumeActivity(token, clearHide);
if (r != null) {
final Activity a = r.activity;
if (localLOGV) Slog.v(
TAG, "Resume " + r + " started activity: " +
a.mStartedActivity + ", hideForNow: " + r.hideForNow
+ ", finished: " + a.mFinished);
final int forwardBit = isForward ?
WindowManager.LayoutParams.SOFT_INPUT_IS_FORWARD_NAVIGATION : 0;
// If the window hasn't yet been added to the window manager,
// and this guy didn't finish itself or start another activity,
// then go ahead and add the window.
boolean willBeVisible = !a.mStartedActivity;
if (!willBeVisible) {
try {
willBeVisible = ActivityManagerNative.getDefault().willActivityBeVisible(
a.getActivityToken());
} catch (RemoteException e) {
}
}
if (r.window == null && !a.mFinished && willBeVisible) {
r.window = r.activity.getWindow();//获取window
View decor = r.window.getDecorView();//获取decor
decor.setVisibility(View.INVISIBLE);
ViewManager wm = a.getWindowManager();//获取windowManager
WindowManager.LayoutParams l = r.window.getAttributes();
a.mDecor = decor;
l.type = WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
l.softInputMode |= forwardBit;
if (a.mVisibleFromClient) {
a.mWindowAdded = true;
wm.addView(decor, l);//把decor添加到windowManager里面
}
// If the window has already been added, but during resume
// we started another activity, then don't yet make the
// window visible.
} else if (!willBeVisible) {
if (localLOGV) Slog.v(
TAG, "Launch " + r + " mStartedActivity set");
r.hideForNow = true;
}
// Get rid of anything left hanging around.
cleanUpPendingRemoveWindows(r);
// The window is now visible if it has been added, we are not
// simply finishing, and we are not starting another activity.
if (!r.activity.mFinished && willBeVisible
&& r.activity.mDecor != null && !r.hideForNow) {
if (r.newConfig != null) {
r.tmpConfig.setTo(r.newConfig);
if (r.overrideConfig != null) {
r.tmpConfig.updateFrom(r.overrideConfig);
}
if (DEBUG_CONFIGURATION) Slog.v(TAG, "Resuming activity "
+ r.activityInfo.name + " with newConfig " + r.tmpConfig);
performConfigurationChanged(r.activity, r.tmpConfig);
freeTextLayoutCachesIfNeeded(r.activity.mCurrentConfig.diff(r.tmpConfig));
r.newConfig = null;
}
if (localLOGV) Slog.v(TAG, "Resuming " + r + " with isForward="
+ isForward);
WindowManager.LayoutParams l = r.window.getAttributes();
if ((l.softInputMode
& WindowManager.LayoutParams.SOFT_INPUT_IS_FORWARD_NAVIGATION)
!= forwardBit) {
l.softInputMode = (l.softInputMode
& (~WindowManager.LayoutParams.SOFT_INPUT_IS_FORWARD_NAVIGATION))
| forwardBit;
if (r.activity.mVisibleFromClient) {
ViewManager wm = a.getWindowManager();
View decor = r.window.getDecorView();
wm.updateViewLayout(decor, l);
}
}
r.activity.mVisibleFromServer = true;
mNumVisibleActivities++;
if (r.activity.mVisibleFromClient) {
r.activity.makeVisible();
}
}
if (!r.onlyLocalRequest) {
r.nextIdle = mNewActivities;
mNewActivities = r;
if (localLOGV) Slog.v(
TAG, "Scheduling idle handler for " + r);
Looper.myQueue().addIdleHandler(new Idler());
}
r.onlyLocalRequest = false;
// Tell the activity manager we have resumed.
if (reallyResume) {
try {
ActivityManagerNative.getDefault().activityResumed(token);
} catch (RemoteException ex) {
}
}
} else {
// If an exception was thrown when trying to resume, then
// just end this activity.
try {
ActivityManagerNative.getDefault()
.finishActivity(token, Activity.RESULT_CANCELED, null, false);
} catch (RemoteException ex) {
}
}
}
performLaunchActivity方法：
private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {
// System.out.println("##### [" + System.currentTimeMillis() + "] ActivityThread.performLaunchActivity(" + r + ")");
ActivityInfo aInfo = r.activityInfo;
if (r.packageInfo == null) {
r.packageInfo = getPackageInfo(aInfo.applicationInfo, r.compatInfo,
Context.CONTEXT_INCLUDE_CODE);
}
ComponentName component = r.intent.getComponent();
if (component == null) {
component = r.intent.resolveActivity(
mInitialApplication.getPackageManager());
r.intent.setComponent(component);
}
if (r.activityInfo.targetActivity != null) {
component = new ComponentName(r.activityInfo.packageName,
r.activityInfo.targetActivity);
}
Activity activity = null;
try {
java.lang.ClassLoader cl = r.packageInfo.getClassLoader();
activity = mInstrumentation.newActivity(//通过反射拿到Activity
cl, component.getClassName(), r.intent);
StrictMode.incrementExpectedActivityCount(activity.getClass());
r.intent.setExtrasClassLoader(cl);
r.intent.prepareToEnterProcess();
if (r.state != null) {
r.state.setClassLoader(cl);
}
} catch (Exception e) {
if (!mInstrumentation.onException(activity, e)) {
throw new RuntimeException(
"Unable to instantiate activity " + component
+ ": " + e.toString(), e);
}
}
try {
Application app = r.packageInfo.makeApplication(false, mInstrumentation);
if (localLOGV) Slog.v(TAG, "Performing launch of " + r);
if (localLOGV) Slog.v(
TAG, r + ": app=" + app
+ ", appName=" + app.getPackageName()
+ ", pkg=" + r.packageInfo.getPackageName()
+ ", comp=" + r.intent.getComponent().toShortString()
+ ", dir=" + r.packageInfo.getAppDir());
if (activity != null) {
Context appContext = createBaseContextForActivity(r, activity);
CharSequence title = r.activityInfo.loadLabel(appContext.getPackageManager());
Configuration config = new Configuration(mCompatConfiguration);
if (DEBUG_CONFIGURATION) Slog.v(TAG, "Launching activity "
+ r.activityInfo.name + " with config " + config);
//activity初始化 PhoneWindow等操作
activity.attach(appContext, this, getInstrumentation(), r.token,
r.ident, app, r.intent, r.activityInfo, title, r.parent,
r.embeddedID, r.lastNonConfigurationInstances, config,
r.referrer, r.voiceInteractor);
if (customIntent != null) {
activity.mIntent = customIntent;
}
r.lastNonConfigurationInstances = null;
activity.mStartedActivity = false;
int theme = r.activityInfo.getThemeResource();
if (theme != 0) {
activity.setTheme(theme);
}
activity.mCalled = false;
if (r.isPersistable()) {
mInstrumentation.callActivityOnCreate(activity, r.state, r.persistentState);//OnCreate生命周期调用
} else {
mInstrumentation.callActivityOnCreate(activity, r.state);
}
if (!activity.mCalled) {
throw new SuperNotCalledException(
"Activity " + r.intent.getComponent().toShortString() +
" did not call through to super.onCreate()");
}
r.activity = activity;
r.stopped = true;
if (!r.activity.mFinished) {
activity.performStart();
r.stopped = false;
}
if (!r.activity.mFinished) {
if (r.isPersistable()) {
if (r.state != null || r.persistentState != null) {
mInstrumentation.callActivityOnRestoreInstanceState(activity, r.state,
r.persistentState);
}
} else if (r.state != null) {
mInstrumentation.callActivityOnRestoreInstanceState(activity, r.state);
}
}
if (!r.activity.mFinished) {
activity.mCalled = false;
if (r.isPersistable()) {
mInstrumentation.callActivityOnPostCreate(activity, r.state,
r.persistentState);
} else {
mInstrumentation.callActivityOnPostCreate(activity, r.state);
}
if (!activity.mCalled) {
throw new SuperNotCalledException(
"Activity " + r.intent.getComponent().toShortString() +
" did not call through to super.onPostCreate()");
}
}
}
r.paused = true;
mActivities.put(r.token, r);
} catch (SuperNotCalledException e) {
throw e;
} catch (Exception e) {
if (!mInstrumentation.onException(activity, e)) {
throw new RuntimeException(
"Unable to start activity " + component
+ ": " + e.toString(), e);
}
}
return activity;
}
callActivityOnCreate方法:
public void callActivityOnCreate(Activity activity, Bundle icicle,
PersistableBundle persistentState) {
prePerformCreate(activity);
activity.performCreate(icicle, persistentState);
postPerformCreate(activity);
}
ViewRootImpl.java:
public void setView(View view, WindowManager.LayoutParams attrs, View panelParentView) { synchronized (this) { if (mView == null) { mView = view;//把dorcor赋值给mView mAttachInfo.mDisplayState = mDisplay.getState(); mDisplayManager.registerDisplayListener(mDisplayListener, mHandler); mViewLayoutDirectionInitial = mView.getRawLayoutDirection(); mFallbackEventHandler.setView(view); mWindowAttributes.copyFrom(attrs); if (mWindowAttributes.packageName == null) { mWindowAttributes.packageName = mBasePackageName; } attrs = mWindowAttributes; // Keep track of the actual window flags supplied by the client. mClientWindowLayoutFlags = attrs.flags; setAccessibilityFocus(null, null); if (view instanceof RootViewSurfaceTaker) { mSurfaceHolderCallback = ((RootViewSurfaceTaker)view).willYouTakeTheSurface(); if (mSurfaceHolderCallback != null) { mSurfaceHolder = new TakenSurfaceHolder(); mSurfaceHolder.setFormat(PixelFormat.UNKNOWN); } } // Compute surface insets required to draw at specified Z value. // TODO: Use real shadow insets for a constant max Z. if (!attrs.hasManualSurfaceInsets) { final int surfaceInset = (int) Math.ceil(view.getZ() * 2); attrs.surfaceInsets.set(surfaceInset, surfaceInset, surfaceInset, surfaceInset); } CompatibilityInfo compatibilityInfo = mDisplayAdjustments.getCompatibilityInfo(); mTranslator = compatibilityInfo.getTranslator(); // If the application owns the surface, don't enable hardware acceleration if (mSurfaceHolder == null) { enableHardwareAcceleration(attrs); } boolean restore = false; if (mTranslator != null) {//动画处理 mSurface.setCompatibilityTranslator(mTranslator); restore = true; attrs.backup(); mTranslator.translateWindowLayout(attrs); } if (DEBUG_LAYOUT) Log.d(TAG, "WindowLayout in setView:" + attrs); if (!compatibilityInfo.supportsScreen()) { attrs.privateFlags |= WindowManager.LayoutParams.PRIVATE_FLAG_COMPATIBLE_WINDOW; mLastInCompatMode = true; } mSoftInputMode = attrs.softInputMode;//输入法处理 mWindowAttributesChanged = true; mWindowAttributesChangesFlag = WindowManager.LayoutParams.EVERYTHING_CHANGED; mAttachInfo.mRootView = view; mAttachInfo.mScalingRequired = mTranslator != null; mAttachInfo.mApplicationScale = mTranslator == null ? 1.0f : mTranslator.applicationScale; if (panelParentView != null) { mAttachInfo.mPanelParentWindowToken = panelParentView.getApplicationWindowToken(); } mAdded = true; int res; /* = WindowManagerImpl.ADD_OKAY; */ // Schedule the first layout -before- adding to the window // manager, to make sure we do the relayout before receiving // any other events from the system. requestLayout();//布局，View和ViewGroup都这该方法 if ((mWindowAttributes.inputFeatures & WindowManager.LayoutParams.INPUT_FEATURE_NO_INPUT_CHANNEL) == 0) { mInputChannel = new InputChannel(); } try { mOrigWindowType = mWindowAttributes.type; mAttachInfo.mRecomputeGlobalAttributes = true; collectViewAttributes(); //发起跨进程消息，把decorView添加显示出来 res = mWindowSession.addToDisplay(mWindow, mSeq, mWindowAttributes, getHostVisibility(), mDisplay.getDisplayId(), mAttachInfo.mContentInsets, mAttachInfo.mStableInsets, mAttachInfo.mOutsets, mInputChannel); } catch (RemoteException e) { mAdded = false; mView = null; mAttachInfo.mRootView = null; mInputChannel = null; mFallbackEventHandler.setView(null); unscheduleTraversals(); setAccessibilityFocus(null, null); throw new RuntimeException("Adding window failed", e); } finally { if (restore) { attrs.restore(); } } if (mTranslator != null) { mTranslator.translateRectInScreenToAppWindow(mAttachInfo.mContentInsets); } mPendingOverscanInsets.set(0, 0, 0, 0); mPendingContentInsets.set(mAttachInfo.mContentInsets); mPendingStableInsets.set(mAttachInfo.mStableInsets); mPendingVisibleInsets.set(0, 0, 0, 0); if (DEBUG_LAYOUT) Log.v(TAG, "Added window " + mWindow); if (res < WindowManagerGlobal.ADD_OKAY) { mAttachInfo.mRootView = null; mAdded = false; mFallbackEventHandler.setView(null); unscheduleTraversals(); setAccessibilityFocus(null, null); switch (res) { case WindowManagerGlobal.ADD_BAD_APP_TOKEN: case WindowManagerGlobal.ADD_BAD_SUBWINDOW_TOKEN: throw new WindowManager.BadTokenException( "Unable to add window -- token " + attrs.token + " is not valid; is your activity running?"); case WindowManagerGlobal.ADD_NOT_APP_TOKEN: throw new WindowManager.BadTokenException( "Unable to add window -- token " + attrs.token + " is not for an application"); case WindowManagerGlobal.ADD_APP_EXITING: throw new WindowManager.BadTokenException( "Unable to add window -- app for token " + attrs.token + " is exiting"); case WindowManagerGlobal.ADD_DUPLICATE_ADD: throw new WindowManager.BadTokenException( "Unable to add window -- window " + mWindow + " has already been added"); case WindowManagerGlobal.ADD_STARTING_NOT_NEEDED: // Silently ignore -- we would have just removed it // right away, anyway. return; case WindowManagerGlobal.ADD_MULTIPLE_SINGLETON: throw new WindowManager.BadTokenException( "Unable to add window " + mWindow + " -- another window of this type already exists"); case WindowManagerGlobal.ADD_PERMISSION_DENIED: throw new WindowManager.BadTokenException( "Unable to add window " + mWindow + " -- permission denied for this window type"); case WindowManagerGlobal.ADD_INVALID_DISPLAY: throw new WindowManager.InvalidDisplayException( "Unable to add window " + mWindow + " -- the specified display can not be found"); case WindowManagerGlobal.ADD_INVALID_TYPE: throw new WindowManager.InvalidDisplayException( "Unable to add window " + mWindow + " -- the specified window type is not valid"); } throw new RuntimeException( "Unable to add window -- unknown error code " + res); } if (view instanceof RootViewSurfaceTaker) { mInputQueueCallback = ((RootViewSurfaceTaker)view).willYouTakeTheInputQueue(); } if (mInputChannel != null) { if (mInputQueueCallback != null) { mInputQueue = new InputQueue(); mInputQueueCallback.onInputQueueCreated(mInputQueue); } mInputEventReceiver = new WindowInputEventReceiver(mInputChannel, Looper.myLooper()); } view.assignParent(this);//调用dorcorView的assignParent方法，将ViewRootImpl传入,将ViewRootImpl设置成dorcorView的mParent mAddedTouchMode = (res & WindowManagerGlobal.ADD_FLAG_IN_TOUCH_MODE) != 0; mAppVisible = (res & WindowManagerGlobal.ADD_FLAG_APP_VISIBLE) != 0; if (mAccessibilityManager.isEnabled()) { mAccessibilityInteractionConnectionManager.ensureConnection(); } if (view.getImportantForAccessibility() == View.IMPORTANT_FOR_ACCESSIBILITY_AUTO) { view.setImportantForAccessibility(View.IMPORTANT_FOR_ACCESSIBILITY_YES); } // Set up the input pipeline. CharSequence counterSuffix = attrs.getTitle(); mSyntheticInputStage = new SyntheticInputStage(); InputStage viewPostImeStage = new ViewPostImeInputStage(mSyntheticInputStage); InputStage nativePostImeStage = new NativePostImeInputStage(viewPostImeStage, "aq:native-post-ime:" + counterSuffix); InputStage earlyPostImeStage = new EarlyPostImeInputStage(nativePostImeStage); InputStage imeStage = new ImeInputStage(earlyPostImeStage, "aq:ime:" + counterSuffix); InputStage viewPreImeStage = new ViewPreImeInputStage(imeStage); InputStage nativePreImeStage = new NativePreImeInputStage(viewPreImeStage, "aq:native-pre-ime:" + counterSuffix); mFirstInputStage = nativePreImeStage; mFirstPostImeInputStage = earlyPostImeStage; mPendingInputEventQueueLengthCounterName = "aq:pending:" + counterSuffix; } } }@Override public void requestLayout() { if (!mHandlingLayoutInLayoutRequest) { checkThread(); mLayoutRequested = true; scheduleTraversals();//遍历操作 } }void scheduleTraversals() { if (!mTraversalScheduled) { mTraversalScheduled = true; mTraversalBarrier = mHandler.getLooper().getQueue().postSyncBarrier(); mChoreographer.postCallback( Choreographer.CALLBACK_TRAVERSAL, mTraversalRunnable, null);//开始一个线程 if (!mUnbufferedInputDispatch) { scheduleConsumeBatchedInput(); } notifyRendererOfFramePending(); pokeDrawLockIfNeeded(); } }
final TraversalRunnable mTraversalRunnable = new TraversalRunnable();final class TraversalRunnable implements Runnable { @Override public void run() { doTraversal();//执行遍历 } }
void doTraversal() { if (mTraversalScheduled) { mTraversalScheduled = false; mHandler.getLooper().getQueue().removeSyncBarrier(mTraversalBarrier); if (mProfile) { Debug.startMethodTracing("ViewAncestor"); } performTraversals();//执行UI绘制的遍历过程 if (mProfile) { Debug.stopMethodTracing(); mProfile = false; } } }
private void performTraversals() { // cache mView since it is used so much below... final View host = mView; if (DBG) { System.out.println("======================================"); System.out.println("performTraversals"); host.debug(); } if (host == null || !mAdded) return; mIsInTraversal = true;//是否正在执行遍历 mWillDrawSoon = true;//是否马上要绘制 boolean windowSizeMayChange = false; boolean newSurface = false; boolean surfaceChanged = false; WindowManager.LayoutParams lp = mWindowAttributes; int desiredWindowWidth;//获取dorcorView的宽 int desiredWindowHeight;//获取dorcorView的高 final int viewVisibility = getHostVisibility(); boolean viewVisibilityChanged = mViewVisibility != viewVisibility || mNewSurfaceNeeded; WindowManager.LayoutParams params = null; if (mWindowAttributesChanged) { mWindowAttributesChanged = false; surfaceChanged = true; params = lp; } CompatibilityInfo compatibilityInfo = mDisplayAdjustments.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; } } mWindowAttributesChangesFlag = 0; Rect frame = mWinFrame; if (mFirst) { mFullRedrawNeeded = true; mLayoutRequested = true; if (lp.type == WindowManager.LayoutParams.TYPE_STATUS_BAR_PANEL || lp.type == WindowManager.LayoutParams.TYPE_INPUT_METHOD) { // NOTE -- system code, won't try to do compat mode. Point size = new Point(); mDisplay.getRealSize(size); desiredWindowWidth = size.x; desiredWindowHeight = size.y; } else { DisplayMetrics packageMetrics = mView.getContext().getResources().getDisplayMetrics(); desiredWindowWidth = packageMetrics.widthPixels; desiredWindowHeight = packageMetrics.heightPixels; } // 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.mHasWindowFocus = false; mAttachInfo.mWindowVisibility = viewVisibility; mAttachInfo.mRecomputeGlobalAttributes = false; viewVisibilityChanged = false; mLastConfiguration.setTo(host.getResources().getConfiguration()); 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(mLastConfiguration.getLayoutDirection()); } host.dispatchAttachedToWindow(mAttachInfo, 0); mAttachInfo.mTreeObserver.dispatchOnWindowAttachedChange(true); dispatchApplyInsets(host); //Log.i(TAG, "Screen on initialized: " + attachInfo.mKeepScreenOn); } else { desiredWindowWidth = frame.width();//根据不同的情况赋值宽高 desiredWindowHeight = frame.height(); if (desiredWindowWidth != mWidth || desiredWindowHeight != mHeight) { if (DEBUG_ORIENTATION) Log.v(TAG, "View " + host + " resized to: " + frame); mFullRedrawNeeded = true; mLayoutRequested = true; windowSizeMayChange = true; } } if (viewVisibilityChanged) { mAttachInfo.mWindowVisibility = viewVisibility; host.dispatchWindowVisibilityChanged(viewVisibility); if (viewVisibility != View.VISIBLE || mNewSurfaceNeeded) { destroyHardwareResources(); } if (viewVisibility == View.GONE) { // After making a window gone, we will count it as being // shown for the first time the next time it gets focus. mHasHadWindowFocus = false; } } // 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 insetsChanged = 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 (!mPendingOverscanInsets.equals(mAttachInfo.mOverscanInsets)) { insetsChanged = true; } if (!mPendingContentInsets.equals(mAttachInfo.mContentInsets)) { insetsChanged = true; } if (!mPendingStableInsets.equals(mAttachInfo.mStableInsets)) { insetsChanged = true; } if (!mPendingVisibleInsets.equals(mAttachInfo.mVisibleInsets)) { mAttachInfo.mVisibleInsets.set(mPendingVisibleInsets); if (DEBUG_LAYOUT) Log.v(TAG, "Visible insets changing to: " + mAttachInfo.mVisibleInsets); } if (!mPendingOutsets.equals(mAttachInfo.mOutsets)) { insetsChanged = true; } if (lp.width == ViewGroup.LayoutParams.WRAP_CONTENT || lp.height == ViewGroup.LayoutParams.WRAP_CONTENT) { windowSizeMayChange = true; if (lp.type == WindowManager.LayoutParams.TYPE_STATUS_BAR_PANEL || lp.type == WindowManager.LayoutParams.TYPE_INPUT_METHOD) { // NOTE -- system code, won't try to do compat mode. Point size = new Point(); mDisplay.getRealSize(size); desiredWindowWidth = size.x; desiredWindowHeight = size.y; } else { DisplayMetrics packageMetrics = res.getDisplayMetrics(); desiredWindowWidth = packageMetrics.widthPixels; desiredWindowHeight = packageMetrics.heightPixels; } } } // 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 (params != null) { if ((host.mPrivateFlags & View.PFLAG_REQUEST_TRANSPARENT_REGIONS) != 0) { if (!PixelFormat.formatHasAlpha(params.format)) { params.format = PixelFormat.TRANSLUCENT; } } mAttachInfo.mOverscanRequested = (params.flags & WindowManager.LayoutParams.FLAG_LAYOUT_IN_OVERSCAN) != 0; } if (mApplyInsetsRequested) { mApplyInsetsRequested = false; mLastOverscanRequested = mAttachInfo.mOverscanRequested; 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)); // 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; if (mFirst || windowShouldResize || insetsChanged || viewVisibilityChanged || params != null) { if (viewVisibility == View.VISIBLE) { // 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 contentInsetsChanged = false; boolean hadSurface = mSurface.isValid(); try { if (DEBUG_LAYOUT) { Log.i(TAG, "host=w:" + host.getMeasuredWidth() + ", h:" + host.getMeasuredHeight() + ", params=" + params); } if (mAttachInfo.mHardwareRenderer != 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.mHardwareRenderer.pauseSurface(mSurface)) { // 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); } final int surfaceGenerationId = mSurface.getGenerationId(); relayoutResult = relayoutWindow(params, viewVisibility, insetsPending); if (DEBUG_LAYOUT) Log.v(TAG, "relayout: frame=" + frame.toShortString() + " overscan=" + mPendingOverscanInsets.toShortString() + " content=" + mPendingContentInsets.toShortString() + " visible=" + mPendingVisibleInsets.toShortString() + " visible=" + mPendingStableInsets.toShortString() + " outsets=" + mPendingOutsets.toShortString() + " surface=" + mSurface); if (mPendingConfiguration.seq != 0) { if (DEBUG_CONFIGURATION) Log.v(TAG, "Visible with new config: " + mPendingConfiguration); updateConfiguration(mPendingConfiguration, !mFirst); mPendingConfiguration.seq = 0; } final boolean overscanInsetsChanged = !mPendingOverscanInsets.equals( mAttachInfo.mOverscanInsets); contentInsetsChanged = !mPendingContentInsets.equals( mAttachInfo.mContentInsets); final boolean visibleInsetsChanged = !mPendingVisibleInsets.equals( mAttachInfo.mVisibleInsets); final boolean stableInsetsChanged = !mPendingStableInsets.equals( mAttachInfo.mStableInsets); final boolean outsetsChanged = !mPendingOutsets.equals(mAttachInfo.mOutsets); if (contentInsetsChanged) { if (mWidth > 0 && mHeight > 0 && lp != null && ((lp.systemUiVisibility|lp.subtreeSystemUiVisibility) & View.SYSTEM_UI_LAYOUT_FLAGS) == 0 && mSurface != null && mSurface.isValid() && !mAttachInfo.mTurnOffWindowResizeAnim && mAttachInfo.mHardwareRenderer != null && mAttachInfo.mHardwareRenderer.isEnabled() && lp != null && !PixelFormat.formatHasAlpha(lp.format) && !mBlockResizeBuffer) { disposeResizeBuffer(); // TODO: Again.... // if (mResizeBuffer == null) { // mResizeBuffer = mAttachInfo.mHardwareRenderer.createDisplayListLayer( // mWidth, mHeight); // } // mResizeBuffer.prepare(mWidth, mHeight, false); // RenderNode layerRenderNode = mResizeBuffer.startRecording(); // HardwareCanvas layerCanvas = layerRenderNode.start(mWidth, mHeight); // try { // final int restoreCount = layerCanvas.save(); // // int yoff; // final boolean scrolling = mScroller != null // && mScroller.computeScrollOffset(); // if (scrolling) { // yoff = mScroller.getCurrY(); // mScroller.abortAnimation(); // } else { // yoff = mScrollY; // } // // layerCanvas.translate(0, -yoff); // if (mTranslator != null) { // mTranslator.translateCanvas(layerCanvas); // } // // RenderNode renderNode = mView.mRenderNode; // if (renderNode != null && renderNode.isValid()) { // layerCanvas.drawDisplayList(renderNode, null, // RenderNode.FLAG_CLIP_CHILDREN); // } else { // mView.draw(layerCanvas); // } // // drawAccessibilityFocusedDrawableIfNeeded(layerCanvas); // // mResizeBufferStartTime = SystemClock.uptimeMillis(); // mResizeBufferDuration = mView.getResources().getInteger( // com.android.internal.R.integer.config_mediumAnimTime); // // layerCanvas.restoreToCount(restoreCount); // layerRenderNode.end(layerCanvas); // layerRenderNode.setCaching(true); // layerRenderNode.setLeftTopRightBottom(0, 0, mWidth, mHeight); // mTempRect.set(0, 0, mWidth, mHeight); // } finally { // mResizeBuffer.endRecording(mTempRect); // } // mAttachInfo.mHardwareRenderer.flushLayerUpdates(); } mAttachInfo.mContentInsets.set(mPendingContentInsets); if (DEBUG_LAYOUT) Log.v(TAG, "Content insets changing to: " + mAttachInfo.mContentInsets); } if (overscanInsetsChanged) { mAttachInfo.mOverscanInsets.set(mPendingOverscanInsets); if (DEBUG_LAYOUT) Log.v(TAG, "Overscan insets changing to: " + mAttachInfo.mOverscanInsets); // Need to relayout with content insets. contentInsetsChanged = true; } if (stableInsetsChanged) { mAttachInfo.mStableInsets.set(mPendingStableInsets); if (DEBUG_LAYOUT) Log.v(TAG, "Decor insets changing to: " + mAttachInfo.mStableInsets); // Need to relayout with content insets. contentInsetsChanged = true; } if (contentInsetsChanged || mLastSystemUiVisibility != mAttachInfo.mSystemUiVisibility || mApplyInsetsRequested || mLastOverscanRequested != mAttachInfo.mOverscanRequested || outsetsChanged) { mLastSystemUiVisibility = mAttachInfo.mSystemUiVisibility; mLastOverscanRequested = mAttachInfo.mOverscanRequested; mAttachInfo.mOutsets.set(mPendingOutsets); mApplyInsetsRequested = false; dispatchApplyInsets(host); } if (visibleInsetsChanged) { mAttachInfo.mVisibleInsets.set(mPendingVisibleInsets); if (DEBUG_LAYOUT) Log.v(TAG, "Visible insets changing to: " + mAttachInfo.mVisibleInsets); } if (!hadSurface) { if (mSurface.isValid()) {//画板初始化，最终的画面都是画到Surface上的，Cavas是从Surface上取一部分出来 // If we are creating a new surface, then we need to // completely redraw it. Also, when we get to the // point of drawing it we will hold off and schedule // a new traversal instead. This is so we can tell the // window manager about all of the windows being displayed // before actually drawing them, so it can display then // all at once. newSurface = true; 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.mHardwareRenderer != null) { try { hwInitialized = mAttachInfo.mHardwareRenderer.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 mSurface.allocateBuffers(); } } catch (OutOfResourcesException e) { handleOutOfResourcesException(e); return; } } } } else if (!mSurface.isValid()) { // 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(); } disposeResizeBuffer(); // Our surface is gone if (mAttachInfo.mHardwareRenderer != null && mAttachInfo.mHardwareRenderer.isEnabled()) { mAttachInfo.mHardwareRenderer.destroy(); } } else if (surfaceGenerationId != mSurface.getGenerationId() && mSurfaceHolder == null && mAttachInfo.mHardwareRenderer != null) { mFullRedrawNeeded = true; try { mAttachInfo.mHardwareRenderer.updateSurface(mSurface); } catch (OutOfResourcesException e) { handleOutOfResourcesException(e); return; } } } 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 (mSurface.isValid()) { if (!hadSurface) { mSurfaceHolder.ungetCallbacks(); mIsCreating = true; mSurfaceHolderCallback.surfaceCreated(mSurfaceHolder); SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks(); if (callbacks != null) { for (SurfaceHolder.Callback c : callbacks) { c.surfaceCreated(mSurfaceHolder); } } surfaceChanged = true; } if (surfaceChanged) { mSurfaceHolderCallback.surfaceChanged(mSurfaceHolder, lp.format, mWidth, mHeight); SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks(); if (callbacks != null) { for (SurfaceHolder.Callback c : callbacks) { c.surfaceChanged(mSurfaceHolder, lp.format, mWidth, mHeight); } } } mIsCreating = false; } else if (hadSurface) { mSurfaceHolder.ungetCallbacks(); SurfaceHolder.Callback callbacks[] = mSurfaceHolder.getCallbacks(); mSurfaceHolderCallback.surfaceDestroyed(mSurfaceHolder); if (callbacks != null) { for (SurfaceHolder.Callback c : callbacks) { c.surfaceDestroyed(mSurfaceHolder); } } mSurfaceHolder.mSurfaceLock.lock(); try { mSurfaceHolder.mSurface = new Surface(); } finally { mSurfaceHolder.mSurfaceLock.unlock(); } } } final HardwareRenderer hardwareRenderer = mAttachInfo.mHardwareRenderer; if (hardwareRenderer != null && hardwareRenderer.isEnabled()) { if (hwInitialized || mWidth != hardwareRenderer.getWidth() || mHeight != hardwareRenderer.getHeight()) { hardwareRenderer.setup(mWidth, mHeight, mAttachInfo, mWindowAttributes.surfaceInsets); if (!hwInitialized) { hardwareRenderer.invalidate(mSurface); mFullRedrawNeeded = true; } } } if (!mStopped || mReportNextDraw) { boolean focusChangedDueToTouchMode = ensureTouchModeLocally( (relayoutResult&WindowManagerGlobal.RELAYOUT_RES_IN_TOUCH_MODE) != 0); if (focusChangedDueToTouchMode || mWidth != host.getMeasuredWidth() || mHeight != host.getMeasuredHeight() || contentInsetsChanged) { int childWidthMeasureSpec = getRootMeasureSpec(mWidth, lp.width); int childHeightMeasureSpec = getRootMeasureSpec(mHeight, lp.height); if (DEBUG_LAYOUT) Log.v(TAG, "Ooops, something changed! mWidth=" + mWidth + " measuredWidth=" + host.getMeasuredWidth() + " mHeight=" + mHeight + " measuredHeight=" + host.getMeasuredHeight() + " coveredInsetsChanged=" + contentInsetsChanged); // Ask host how big it wants to be performMeasure(childWidthMeasureSpec, childHeightMeasureSpec);//测量控件需要多大 // 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(TAG, "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. // TODO: Well, we are checking whether the frame has changed similarly // to how this is done for the insets. This is however incorrect since // the insets and the frame are translated. For example, the old frame // was (1, 1 - 1, 1) and was translated to say (2, 2 - 2, 2), now the new // reported frame is (2, 2 - 2, 2) which implies no change but this is not // true since we are comparing a not translated value to a translated one. // This scenario is rare but we may want to fix that. final boolean windowMoved = (mAttachInfo.mWindowLeft != frame.left || mAttachInfo.mWindowTop != frame.top); if (windowMoved) { if (mTranslator != null) { mTranslator.translateRectInScreenToAppWinFrame(frame); } mAttachInfo.mWindowLeft = frame.left; mAttachInfo.mWindowTop = frame.top; // Update the light position for the new window offsets. if (mAttachInfo.mHardwareRenderer != null) { mAttachInfo.mHardwareRenderer.setLightCenter(mAttachInfo); } } } final boolean didLayout = layoutRequested && (!mStopped || mReportNextDraw); boolean triggerGlobalLayoutListener = didLayout || mAttachInfo.mRecomputeGlobalAttributes; if (didLayout) { performLayout(lp, desiredWindowWidth, desiredWindowHeight); //布局控件 // 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 (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) { } } } boolean skipDraw = false; if (mFirst) { // handle first focus request if (DEBUG_INPUT_RESIZE) Log.v(TAG, "First: mView.hasFocus()=" + mView.hasFocus()); if (mView != null) { if (!mView.hasFocus()) { mView.requestFocus(View.FOCUS_FORWARD); if (DEBUG_INPUT_RESIZE) Log.v(TAG, "First: requested focused view=" + mView.findFocus()); } else { if (DEBUG_INPUT_RESIZE) Log.v(TAG, "First: existing focused view=" + mView.findFocus()); } } } else if (mWindowsAnimating) { if (mRemainingFrameCount <= 0) { skipDraw = true; } mRemainingFrameCount--; } mFirst = false; mWillDrawSoon = false; mNewSurfaceNeeded = false; mViewVisibility = viewVisibility; if (mAttachInfo.mHasWindowFocus && !isInLocalFocusMode()) { final boolean imTarget = WindowManager.LayoutParams .mayUseInputMethod(mWindowAttributes.flags); if (imTarget != mLastWasImTarget) { mLastWasImTarget = imTarget; InputMethodManager imm = InputMethodManager.peekInstance(); if (imm != null && imTarget) { imm.onPreWindowFocus(mView, true /* hasWindowFocus */); imm.onPostWindowFocus(mView, mView.findFocus(), mWindowAttributes.softInputMode, !mHasHadWindowFocus, mWindowAttributes.flags); } } } // Remember if we must report the next draw. if ((relayoutResult & WindowManagerGlobal.RELAYOUT_RES_FIRST_TIME) != 0) { mReportNextDraw = true; } boolean cancelDraw = mAttachInfo.mTreeObserver.dispatchOnPreDraw() || viewVisibility != View.VISIBLE; if (!cancelDraw && !newSurface) { if (!skipDraw || mReportNextDraw) { if (mPendingTransitions != null && mPendingTransitions.size() > 0) { for (int i = 0; i < mPendingTransitions.size(); ++i) { mPendingTransitions.get(i).startChangingAnimations(); } mPendingTransitions.clear(); } performDraw(); //渲染控件 } } else { if (viewVisibility == View.VISIBLE) { // Try again scheduleTraversals(); } else if (mPendingTransitions != null && mPendingTransitions.size() > 0) { for (int i = 0; i < mPendingTransitions.size(); ++i) { mPendingTransitions.get(i).endChangingAnimations(); } mPendingTransitions.clear(); } } mIsInTraversal = false; }
思路图：
总结：
最终调用了ViewRootImpl.setView
在setview方法里调用了view.assignParent(this);,将Decorview的mParent设置成ViewRootImpl
这也就是为什么View再用requestLayout方法的时候最终会走到ViewRootImpl的requestLayout
