Activity的启动：
Activity之间的跳转只需要一句startActivity(intent)，但背后包含了进程间通信和进程内通信等等很多步骤。
冷启动
冷启动指，后台不存在的情况下，从桌面或者其他地方打开APP，桌面其实也是一个APP，我们称为Launcher。
Activity之间的跳转
进程间通信
- startActivity()->AMS
我们在跳转activity的时候，会用到startActivity()或者startActivityForResult()，其实最终都会跳转到startActivityForResult()，我们来看看这个方法：
public void startActivityForResult(@RequiresPermission Intent intent, int requestCode,
@Nullable Bundle options) {
if (mParent == null) {
Instrumentation.ActivityResult ar =
mInstrumentation.execStartActivity(
this, mMainThread.getApplicationThread(), mToken, this,
intent, requestCode, options);
// 仪表盘Instrumentation帮助我们启动Activity
if (requestCode >= 0) {
// 源代码注释说了一大堆，翻译一下就是把这个activity隐藏了，直到下个activity finish收到结果
// TODO
mStartedActivity = true;
}
......
看一下Instrumentation是怎么启动的
public ActivityResult execStartActivity(
Context who, IBinder contextThread, IBinder token, Activity target,
Intent intent, int requestCode, Bundle options) {
if (mActivityMonitors != null) {
// ActivityMonitors类用于InstrumentationTest的相关测试类
// TODO
}
try {
int result = ActivityTaskManager.getService().startActivity(whoThread,
who.getOpPackageName(), who.getAttributionTag(), intent,
intent.resolveTypeIfNeeded(who.getContentResolver()), token,
target != null ? target.mEmbeddedID : null, requestCode, 0, null, options);
checkStartActivityResult(result, intent);
}
return null;
}
进程内
ActivityThread -> Activity
两条主线context、window
Activity#handleLaunchActivity()
Activity#performLaunchActivity()
performLaunchActivity()#mInstrumentation.newActivity() 创建Activity
performLaunchActivity()#Activty.attach
ActivityThread#handleLaunchActivity()
public Activity handleLaunchActivity(ActivityClientRecord r,
PendingTransactionActions pendingActions, Intent customIntent) {
// 取消Gc防止被销毁
unscheduleGcIdler();
// TODO : What HardwareRenderer
if (ThreadedRenderer.sRendererEnabled
&& (r.activityInfo.flags & ActivityInfo.FLAG_HARDWARE_ACCELERATED) != 0) {
HardwareRenderer.preload();
}
// WindowManagerGlobal的初始化
WindowManagerGlobal.initialize();
// TODO : Hint the GraphicsEnvironment that an activity is launching on the process.
GraphicsEnvironment.hintActivityLaunch();
// 开始 performLaunchActivity
final Activity a = performLaunchActivity(r, customIntent);
return a;
}
ActivityThread#performLaunchActivity()
private Activity performLaunchActivity(ActivityClientRecord r, Intent customIntent) {
// r包含了当前包名，目标Activity信息，theme等等，会进行对比从而控制跳转
ActivityInfo aInfo = r.activityInfo;
// 创建ContextImpl
ContextImpl appContext = createBaseContextForActivity(r);
// Instrumentation.newActivity创建
Activity activity = null;
try {
java.lang.ClassLoader cl = appContext.getClassLoader();
activity = mInstrumentation.newActivity(
cl, component.getClassName(), r.intent);
StrictMode.incrementExpectedActivityCount(activity.getClass());
r.intent.setExtrasClassLoader(cl);
r.intent.prepareToEnterProcess(isProtectedComponent(r.activityInfo),
appContext.getAttributionSource());
}
// 开始activity.attach
if (activity != null) {
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, window, r.activityConfigCallback,
r.assistToken, r.shareableActivityToken);
//
if (customIntent != null) {
activity.mIntent = customIntent;
}
int theme = r.activityInfo.getThemeResource();
if (theme != 0) {
activity.setTheme(theme);
}
// TODO : mLaunchedFromBubble
activity.mLaunchedFromBubble = r.mLaunchedFromBubble;
// Instrumentation让Activity#performCreate，进入onCreate周期
r.activity = activity;
if (r.isPersistable()) {
mInstrumentation.callActivityOnCreate(activity, r.state, r.persistentState);
} else {
mInstrumentation.callActivityOnCreate(activity, r.state);
}
return activity;
}
}
Activty#attach()
final void attach(Context context, ActivityThread aThread,
Instrumentation instr, IBinder token, int ident,
Application application, Intent intent, ActivityInfo info,
CharSequence title, Activity parent, String id,
NonConfigurationInstances lastNonConfigurationInstances,
Configuration config, String referrer, IVoiceInteractor voiceInteractor,
Window window, ActivityConfigCallback activityConfigCallback, IBinder assistToken,
IBinder shareableActivityToken) {
// performLaunchActivity中创建的contextImpl赋值给ThemeWrapper的mBase，从而能够使用Context的唯一实现类ContextImpl
attachBaseContext(context);
// 创建PhoneWindow
mWindow = new PhoneWindow(this, window, activityConfigCallback);
mWindow.setWindowControllerCallback(mWindowControllerCallback);
mWindow.setCallback(this);
mWindow.setOnWindowDismissedCallback(this);
// 初始化LayoutInflater
mWindow.getLayoutInflater().setPrivateFactory(this);
// 初始化WindowManager
mWindow.setWindowManager(
(WindowManager)context.getSystemService(Context.WINDOW_SERVICE),
mToken, mComponent.flattenToString(),
(info.flags & ActivityInfo.FLAG_HARDWARE_ACCELERATED) != 0);
if (mParent != null) {
mWindow.setContainer(mParent.getWindow());
}
mWindowManager = mWindow.getWindowManager();
getAutofillClientController().onActivityAttached(application);
setContentCaptureOptions(application.getContentCaptureOptions());
}
}
在attach中创建了PhoneWindow、LayoutInflater、WindowManager
之后有两个分支，Activity和AppCompatActivity，我们直接看AppCompatActivity
onCreate()
- 首先会执行onCreate()方法中的 getDelegate() 创建一个AppCompatDelegate,AppCompatDelegate的实现类为AppCompatDelegateImpl
- AppCompatDelegateImpl#installViewFactory(), 来初始化LayoutInflater.Factory2
- Factory2创建view
- AppCompatDelegateImpl#onCreate()，版本适配
- AppCompatDelegateImpl#setContentView()创建DecorView，初始化布局(Activity在PhoneWindow#setContentView实现) AppCompatDelegateImpl#ensureSubDecor()-> createSubDecor()-> PhoneWindow#setContentView(View)->installDecor()->generateLayout()来创建mSubDecor,初始化布局
- AppCompatDelegateImpl#setContentView->setContentView#LayoutInflater.from(mContext).inflate(resId, contentParent)->from#ContextImpl.getSystemService() 注册，LayoutInflater初始化
- LayoutInflater#createViewFromTag()->mFactory2.onCreateView()或反射返回view
onCreate()
在AppCompatActivity没有onCreate()，构造函数主要是加载Factory、AppCompatDelegate 在Activity没有构造函数，onCreate()方法主要是和Actionbar和savedInstanceState转Parcelable存储相关
构造函数
通过new Activity后，我们首先会进入到构造函数，
先看看AppCompatActivity类的初始化
public AppCompatActivity() {
super();
initDelegate();
}
private void initDelegate() {
// TODO: Directly connect AppCompatDelegate to SavedStateRegistry
getSavedStateRegistry().registerSavedStateProvider(DELEGATE_TAG,
new SavedStateRegistry.SavedStateProvider() {
@NonNull
@Override
public Bundle saveState() {
Bundle outState = new Bundle();
getDelegate().onSaveInstanceState(outState);
return outState;
}
});
addOnContextAvailableListener(new OnContextAvailableListener() {
@Override
public void onContextAvailable(@NonNull Context context) {
final AppCompatDelegate delegate = getDelegate();
delegate.installViewFactory(); // 入口一
delegate.onCreate(getSavedStateRegistry() // 入口二
.consumeRestoredStateForKey(DELEGATE_TAG));
}
});
}
- 入口一 AppCompatDelegateImpl#installViewFactory(), 来初始化LayoutInflater.Factory2
public void installViewFactory() {
LayoutInflater layoutInflater = LayoutInflater.from(mContext);
if (layoutInflater.getFactory() == null) {
LayoutInflaterCompat.setFactory2(layoutInflater, this);
} else {
if (!(layoutInflater.getFactory2() instanceof AppCompatDelegateImpl)) {
Log.i(TAG, "The Activity's LayoutInflater already has a Factory installed"
+ " so we can not install AppCompat's");
}
}
}
AppCompatDelegateImpl.onCreate(savedInstanceState);这个是入口二
@Override
public void onCreate(Bundle savedInstanceState) {
// attachBaseContext will only be called from an Activity, so make sure we switch this for
// Dialogs, etc
mBaseContextAttached = true;
// Our implicit call to applyDayNight() should not recreate until after the Activity is
// created
applyDayNight(false);
// We lazily fetch the Window for Activities, to allow DayNight to apply in
// attachBaseContext
ensureWindow();
if (mHost instanceof Activity) {
String parentActivityName = null;
try {
parentActivityName = NavUtils.getParentActivityName((Activity) mHost);
} catch (IllegalArgumentException iae) {
// Ignore in this case
}
if (parentActivityName != null) {
// Peek at the Action Bar and update it if it already exists
ActionBar ab = peekSupportActionBar();
if (ab == null) {
mEnableDefaultActionBarUp = true;
} else {
ab.setDefaultDisplayHomeAsUpEnabled(true);
}
}
// Only activity-hosted delegates should apply night mode changes.
addActiveDelegate(this);
}
mEffectiveConfiguration = new Configuration(mContext.getResources().getConfiguration());
mCreated = true;
}
AppCompatDelegateImpl构造之后，我们调用setContentView()
AppCompatActivity的setContentView()
两者的区别就是分别从AppCompatDelegateImpl,PhoneWindow开始LayoutInflater.from(mContext).inflate(resId, contentParent);
AppCompatActivity中的构造函数会初始化Factory，从而替换View
Factory,Factory2只是两个接口，只有onCreateView方法
AppCompatDelegateImpl#setContentView
public void setContentView(int resId) {
// 创建DecorView
ensureSubDecor();
ViewGroup contentParent = mSubDecor.findViewById(android.R.id.content);
contentParent.removeAllViews();
LayoutInflater.from(mContext).inflate(resId, contentParent);
mAppCompatWindowCallback.getWrapped().onContentChanged();
}
LayoutInflaterCompat#inflate()
public View inflate(XmlPullParser parser, @Nullable ViewGroup root, boolean attachToRoot(root != null)) {
synchronized (mConstructorArgs) {
Trace.traceBegin(Trace.TRACE_TAG_VIEW, "inflate");
final Context inflaterContext = mContext;
final AttributeSet attrs = Xml.asAttributeSet(parser);
Context lastContext = (Context) mConstructorArgs[0];
mConstructorArgs[0] = inflaterContext;
View result = root;
try {
advanceToRootNode(parser);
final String name = parser.getName();
if (DEBUG) {
System.out.println("**************************");
System.out.println("Creating root view: " + name);
System.out.println("**************************");
}
if (TAG_MERGE.equals(name)) {
if (root == null || !attachToRoot) {
throw new InflateException("<merge /> can be used only with a valid "
+ "ViewGroup root and attachToRoot=true");
}
rInflate(parser, root, inflaterContext, attrs, false);
} else {
// Temp is the root view that was found in the xml
final View temp = createViewFromTag(root, name, inflaterContext, attrs);
ViewGroup.LayoutParams params = null;
if (root != null) {
if (DEBUG) {
System.out.println("Creating params from root: " +
root);
}
// Create layout params that match root, if supplied
params = root.generateLayoutParams(attrs);
if (!attachToRoot) {
// Set the layout params for temp if we are not
// attaching. (If we are, we use addView, below)
temp.setLayoutParams(params);
}
}
if (DEBUG) {
System.out.println("-----> start inflating children");
}
// Inflate all children under temp against its context.
rInflateChildren(parser, temp, attrs, true);
if (DEBUG) {
System.out.println("-----> done inflating children");
}
// We are supposed to attach all the views we found (int temp)
// to root. Do that now.
if (root != null && attachToRoot) {
root.addView(temp, params);
}
// Decide whether to return the root that was passed in or the
// top view found in xml.
if (root == null || !attachToRoot) {
result = temp;
}
}
} catch (XmlPullParserException e) {
final InflateException ie = new InflateException(e.getMessage(), e);
ie.setStackTrace(EMPTY_STACK_TRACE);
throw ie;
} catch (Exception e) {
final InflateException ie = new InflateException(
getParserStateDescription(inflaterContext, attrs)
+ ": " + e.getMessage(), e);
ie.setStackTrace(EMPTY_STACK_TRACE);
throw ie;
} finally {
// Don't retain static reference on context.
mConstructorArgs[0] = lastContext;
mConstructorArgs[1] = null;
Trace.traceEnd(Trace.TRACE_TAG_VIEW);
}
return result;
}
}
View createViewFromTag(View parent, String name, Context context, AttributeSet attrs,
boolean ignoreThemeAttr) {
if (name.equals("view")) {
name = attrs.getAttributeValue(null, "class");
}
// Apply a theme wrapper, if allowed and one is specified.
if (!ignoreThemeAttr) {
final TypedArray ta = context.obtainStyledAttributes(attrs, ATTRS_THEME);
final int themeResId = ta.getResourceId(0, 0);
if (themeResId != 0) {
context = new ContextThemeWrapper(context, themeResId);
}
ta.recycle();
}
try {
// 替换view为AppCompatView
View view = tryCreateView(parent, name, context, attrs);
if (view == null) {
final Object lastContext = mConstructorArgs[0];
mConstructorArgs[0] = context;
try {
if (-1 == name.indexOf('.')) {
view = onCreateView(context, parent, name, attrs);
} else {
view = createView(context, name, null, attrs);
}
} finally {
mConstructorArgs[0] = lastContext;
}
}
return view;
} catch (InflateException e) {
throw e;
} catch (ClassNotFoundException e) {
final InflateException ie = new InflateException(
getParserStateDescription(context, attrs)
+ ": Error inflating class " + name, e);
ie.setStackTrace(EMPTY_STACK_TRACE);
throw ie;
} catch (Exception e) {
final InflateException ie = new InflateException(
getParserStateDescription(context, attrs)
+ ": Error inflating class " + name, e);
ie.setStackTrace(EMPTY_STACK_TRACE);
throw ie;
}
}
public final View tryCreateView(@Nullable View parent, @NonNull String name,
@NonNull Context context,
@NonNull AttributeSet attrs) {
if (name.equals(TAG_1995)) {
// Let's party like it's 1995!
return new BlinkLayout(context, attrs);
}
View view;
if (mFactory2 != null) {
view = mFactory2.onCreateView(parent, name, context, attrs);
} else if (mFactory != null) {
view = mFactory.onCreateView(name, context, attrs);
} else {
view = null;
}
if (view == null && mPrivateFactory != null) {
view = mPrivateFactory.onCreateView(parent, name, context, attrs);
}
return view;
}
之前setFactory()是AppCompatDelegateImpl
public View createView(View parent, final String name, @NonNull Context context,
@NonNull AttributeSet attrs) {
if (mAppCompatViewInflater == null) {
TypedArray a = mContext.obtainStyledAttributes(R.styleable.AppCompatTheme);
String viewInflaterClassName =
a.getString(R.styleable.AppCompatTheme_viewInflaterClass);
if (viewInflaterClassName == null) {
// Set to null (the default in all AppCompat themes). Create the base inflater
// (no reflection)
mAppCompatViewInflater = new AppCompatViewInflater();
} else {
try {
Class<?> viewInflaterClass =
mContext.getClassLoader().loadClass(viewInflaterClassName);
mAppCompatViewInflater =
(AppCompatViewInflater) viewInflaterClass.getDeclaredConstructor()
.newInstance();
} catch (Throwable t) {
Log.i(TAG, "Failed to instantiate custom view inflater "
+ viewInflaterClassName + ". Falling back to default.", t);
mAppCompatViewInflater = new AppCompatViewInflater();
}
}
}
boolean inheritContext = false;
if (IS_PRE_LOLLIPOP) {
if (mLayoutIncludeDetector == null) {
mLayoutIncludeDetector = new LayoutIncludeDetector();
}
if (mLayoutIncludeDetector.detect(attrs)) {
// The view being inflated is the root of an <include>d view, so make sure
// we carry over any themed context.
inheritContext = true;
} else {
inheritContext = (attrs instanceof XmlPullParser)
// If we have a XmlPullParser, we can detect where we are in the layout
? ((XmlPullParser) attrs).getDepth() > 1
// Otherwise we have to use the old heuristic
: shouldInheritContext((ViewParent) parent);
}
}
return mAppCompatViewInflater.createView(parent, name, context, attrs, inheritContext,
IS_PRE_LOLLIPOP, /* Only read android:theme pre-L (L+ handles this anyway) */
true, /* Read read app:theme as a fallback at all times for legacy reasons */
VectorEnabledTintResources.shouldBeUsed() /* Only tint wrap the context if enabled */
);
}
AppCompatViewInflater.createView
final View createView(View parent, final String name, @NonNull Context context,
@NonNull AttributeSet attrs, boolean inheritContext,
boolean readAndroidTheme, boolean readAppTheme, boolean wrapContext) {
final Context originalContext = context;
// We can emulate Lollipop's android:theme attribute propagating down the view hierarchy
// by using the parent's context
if (inheritContext && parent != null) {
context = parent.getContext();
}
if (readAndroidTheme || readAppTheme) {
// We then apply the theme on the context, if specified
context = themifyContext(context, attrs, readAndroidTheme, readAppTheme);
}
if (wrapContext) {
context = TintContextWrapper.wrap(context);
}
View view = null;
// We need to 'inject' our tint aware Views in place of the standard framework versions
switch (name) {
case "TextView":
view = createTextView(context, attrs);
verifyNotNull(view, name);
break;
case "ImageView":
view = createImageView(context, attrs);
verifyNotNull(view, name);
break;
case "Button":
view = createButton(context, attrs);
verifyNotNull(view, name);
break;
case "EditText":
view = createEditText(context, attrs);
verifyNotNull(view, name);
break;
case "Spinner":
view = createSpinner(context, attrs);
verifyNotNull(view, name);
break;
case "ImageButton":
view = createImageButton(context, attrs);
verifyNotNull(view, name);
break;
case "CheckBox":
view = createCheckBox(context, attrs);
verifyNotNull(view, name);
break;
case "RadioButton":
view = createRadioButton(context, attrs);
verifyNotNull(view, name);
break;
case "CheckedTextView":
view = createCheckedTextView(context, attrs);
verifyNotNull(view, name);
break;
case "AutoCompleteTextView":
view = createAutoCompleteTextView(context, attrs);
verifyNotNull(view, name);
break;
case "MultiAutoCompleteTextView":
view = createMultiAutoCompleteTextView(context, attrs);
verifyNotNull(view, name);
break;
case "RatingBar":
view = createRatingBar(context, attrs);
verifyNotNull(view, name);
break;
case "SeekBar":
view = createSeekBar(context, attrs);
verifyNotNull(view, name);
break;
case "ToggleButton":
view = createToggleButton(context, attrs);
verifyNotNull(view, name);
break;
default:
// The fallback that allows extending class to take over view inflation
// for other tags. Note that we don't check that the result is not-null.
// That allows the custom inflater path to fall back on the default one
// later in this method.
view = createView(context, name, attrs);
}
if (view == null && originalContext != context) {
// If the original context does not equal our themed context, then we need to manually
// inflate it using the name so that android:theme takes effect.
view = createViewFromTag(context, name, attrs);
}
if (view != null) {
// If we have created a view, check its android:onClick
checkOnClickListener(view, attrs);
backportAccessibilityAttributes(context, view, attrs);
}
return view;
}
Activity的setContentView()
public void setContentView(@LayoutRes int layoutResID) {
getWindow().setContentView(layoutResID);
initWindowDecorActionBar();
}
actionBar我们不看，Window的唯一实现类是PhoneWindow 所以直接看PhoneWindow
public void setContentView(int layoutResID) {
// Note: FEATURE_CONTENT_TRANSITIONS may be set in the process of installing the window
// decor, when theme attributes and the like are crystalized. Do not check the feature
// before this happens.
if (mContentParent == null) {
installDecor();
} else if (!hasFeature(FEATURE_CONTENT_TRANSITIONS)) {
mContentParent.removeAllViews();
}
if (hasFeature(FEATURE_CONTENT_TRANSITIONS)) {
final Scene newScene = Scene.getSceneForLayout(mContentParent, layoutResID,
getContext());
transitionTo(newScene);
} else {
// 走向和AppCompatActivity一样的道路，只不过mFactory==null，不会去替换
mLayoutInflater.inflate(layoutResID, mContentParent);
}
mContentParent.requestApplyInsets();
final Callback cb = getCallback();
if (cb != null && !isDestroyed()) {
cb.onContentChanged();
}
mContentParentExplicitlySet = true;
}
创建decorView,View
onStart
handleStartActivity
onResume
handleResumeActivity
public void handleResumeActivity(ActivityClientRecord r, boolean finalStateRequest,
boolean isForward, String reason) {
// 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
// skip below steps for double-resume and r.mFinish = true case.
// 入口
if (!performResumeActivity(r, finalStateRequest, reason)) {
return;
}
if (mActivitiesToBeDestroyed.containsKey(r.token)) {
// Although the activity is resumed, it is going to be destroyed. So the following
// UI operations are unnecessary and also prevents exception because its token may
// be gone that window manager cannot recognize it. All necessary cleanup actions
// performed below will be done while handling destruction.
return;
}
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) {
willBeVisible = ActivityClient.getInstance().willActivityBeVisible(
a.getActivityToken());
}
if (r.window == null && !a.mFinished && willBeVisible) {
r.window = r.activity.getWindow();
View decor = r.window.getDecorView();
decor.setVisibility(View.INVISIBLE);
ViewManager wm = a.getWindowManager();
WindowManager.LayoutParams l = r.window.getAttributes();
a.mDecor = decor;
l.type = WindowManager.LayoutParams.TYPE_BASE_APPLICATION;
l.softInputMode |= forwardBit;
if (r.mPreserveWindow) {
a.mWindowAdded = true;
r.mPreserveWindow = false;
// Normally the ViewRoot sets up callbacks with the Activity
// in addView->ViewRootImpl#setView. If we are instead reusing
// the decor view we have to notify the view root that the
// callbacks may have changed.
ViewRootImpl impl = decor.getViewRootImpl();
if (impl != null) {
impl.notifyChildRebuilt();
}
}
if (a.mVisibleFromClient) {
if (!a.mWindowAdded) {
// 添加decor到windowManager
a.mWindowAdded = true;
wm.addView(decor, l);
} else {
// The activity will get a callback for this {@link LayoutParams} change
// earlier. However, at that time the decor will not be set (this is set
// in this method), so no action will be taken. This call ensures the
// callback occurs with the decor set.
a.onWindowAttributesChanged(l);
}
}
// 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, false /* force */);
// 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 (localLOGV) Slog.v(TAG, "Resuming " + r + " with isForward=" + isForward);
ViewRootImpl impl = r.window.getDecorView().getViewRootImpl();
WindowManager.LayoutParams l = impl != null
? impl.mWindowAttributes : 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();
}
}
r.nextIdle = mNewActivities;
mNewActivities = r;
if (localLOGV) Slog.v(TAG, "Scheduling idle handler for " + r);
Looper.myQueue().addIdleHandler(new Idler());
}
public boolean performResumeActivity(ActivityClientRecord r, boolean finalStateRequest,
String reason) {
if (localLOGV) {
Slog.v(TAG, "Performing resume of " + r + " finished=" + r.activity.mFinished);
}
if (r.activity.mFinished) {
return false;
}
if (r.getLifecycleState() == ON_RESUME) {
if (!finalStateRequest) {
final RuntimeException e = new IllegalStateException(
"Trying to resume activity which is already resumed");
Slog.e(TAG, e.getMessage(), e);
Slog.e(TAG, r.getStateString());
// TODO(lifecycler): A double resume request is possible when an activity
// receives two consequent transactions with relaunch requests and "resumed"
// final state requests and the second relaunch is omitted. We still try to
// handle two resume requests for the final state. For cases other than this
// one, we don't expect it to happen.
}
return false;
}
if (finalStateRequest) {
r.hideForNow = false;
r.activity.mStartedActivity = false;
}
try {
r.activity.onStateNotSaved();
r.activity.mFragments.noteStateNotSaved();
checkAndBlockForNetworkAccess();
if (r.pendingIntents != null) {
deliverNewIntents(r, r.pendingIntents);
r.pendingIntents = null;
}
if (r.pendingResults != null) {
deliverResults(r, r.pendingResults, reason);
r.pendingResults = null;
}
// 入口
r.activity.performResume(r.startsNotResumed, reason);
r.state = null;
r.persistentState = null;
r.setState(ON_RESUME);
reportTopResumedActivityChanged(r, r.isTopResumedActivity, "topWhenResuming");
} catch (Exception e) {
if (!mInstrumentation.onException(r.activity, e)) {
throw new RuntimeException("Unable to resume activity "
+ r.intent.getComponent().toShortString() + ": " + e.toString(), e);
}
}
return true;
}
final void performResume(boolean followedByPause, String reason) {
if (Trace.isTagEnabled(Trace.TRACE_TAG_WINDOW_MANAGER)) {
Trace.traceBegin(Trace.TRACE_TAG_WINDOW_MANAGER, "performResume:"
+ mComponent.getClassName());
}
dispatchActivityPreResumed();
performRestart(true /* start */, reason);
mFragments.execPendingActions();
mLastNonConfigurationInstances = null;
getAutofillClientController().onActivityPerformResume(followedByPause);
mCalled = false;
// mResumed is set by the instrumentation
// 唤醒Resume，入口
mInstrumentation.callActivityOnResume(this);
EventLogTags.writeWmOnResumeCalled(mIdent, getComponentName().getClassName(), reason);
if (!mCalled) {
throw new SuperNotCalledException(
"Activity " + mComponent.toShortString() +
" did not call through to super.onResume()");
}
// invisible activities must be finished before onResume) completes
if (!mVisibleFromClient && !mFinished) {
Log.w(TAG, "An activity without a UI must call finish() before onResume() completes");
if (getApplicationInfo().targetSdkVersion
> android.os.Build.VERSION_CODES.LOLLIPOP_MR1) {
throw new IllegalStateException(
"Activity " + mComponent.toShortString() +
" did not call finish() prior to onResume() completing");
}
}
// Now really resume, and install the current status bar and menu.
mCalled = false;
mFragments.dispatchResume();
mFragments.execPendingActions();
onPostResume();
if (!mCalled) {
throw new SuperNotCalledException(
"Activity " + mComponent.toShortString() +
" did not call through to super.onPostResume()");
}
dispatchActivityPostResumed();
Trace.traceEnd(Trace.TRACE_TAG_WINDOW_MANAGER);
}
public void callActivityOnResume(Activity activity) {
activity.mResumed = true;
activity.onResume();
if (mActivityMonitors != null) {
synchronized (mSync) {
final int N = mActivityMonitors.size();
for (int i=0; i<N; i++) {
final ActivityMonitor am = mActivityMonitors.get(i);
am.match(activity, activity, activity.getIntent());
}
}
}
}
这些handleXXXActivity应该都是ManangerService发送过来的由TransactionExecutor这个类处理
// www.jianshu.com/p/9da7bfe18… onCreate onStart // blog.csdn.net/lixiong0713… 屏幕刷新
启动之后的绘制
// www.jianshu.com/p/9da7bfe18… onCreate onStart // blog.csdn.net/lixiong0713… 屏幕刷新
- Factory2创建view
- AppCompatDelegateImpl#onCreate()，版本适配
- AppCompatDelegateImpl#setContentView()创建DecorView，初始化布局(Activity在PhoneWindow#setContentView实现) AppCompatDelegateImpl#ensureSubDecor()-> createSubDecor()-> PhoneWindow#setContentView(View)->installDecor()->generateLayout()来创建mSubDecor,初始化布局
- AppCompatDelegateImpl#setContentView->setContentView#LayoutInflater.from(mContext).inflate(resId, contentParent)->from#ContextImpl.getSystemService() 注册，LayoutInflater初始化
- LayoutInflater#createViewFromTag()->mFactory2.onCreateView()或反射返回view
onStart()
handleResumeActivity()
onResume()
DecorView添加到windowManager ViewRootImpl创建 WindowManagerImpl -> WindowManagerGlobal -> ViewRootImpl开始绘制 Decorview.visiable
class PhoneWindow extends (abstract)Window
Window主要提供了窗口操作的方法，比如背景标题ContentView等等； PhoneWindow是实现Window的唯一子类，它里面实现了各种添加背景主题ContentView的方法，内部通过DecorView来添加顶级视图。
interface WindowManager extends (interface cud view)ViewManager
ViewManager定义了view的add,update,remove, ViewGroup实现了这一接口
WindowManager用来在应用与Window之间的接口、窗口顺序、消息等的管理，是由WindowManagerImpl实现
class WindowManagerImpl implements (interface)WindowManager
/**WindowManagerImpl
- The top of a view hierarchy, implementing the needed protocol between View
- and the WindowManager. This is for the most part an internal implementation
- detail of {@link WindowManagerGlobal}.
- {@hide} */
