WindowManagerServices Android 7（一）

Window是一个abstact类型,唯一继承Window的类为PhoneWindow，PhoneWindow在Android7 中位于framework/base/core/java/com/android/internal/policy/PhoneWindow.java中。

PhoneWindow对象在Activity对象创建以后再创建，ActivityThread.java中

  case LAUNCH_ACTIVITY: {                    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, "LAUNCH_ACTIVITY");                    Trace.traceEnd(Trace.TRACE_TAG_ACTIVITY_MANAGER);                } break;

private void handleLaunchActivity(ActivityClientRecord r, Intent customIntent, 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;        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);        if (a != null) {            r.createdConfig = new Configuration(mConfiguration);            reportSizeConfigurations(r);            Bundle oldState = r.state;            handleResumeActivity(r.token, false, r.isForward,                    !r.activity.mFinished && !r.startsNotResumed, r.lastProcessedSeq, reason);            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.                performPauseActivityIfNeeded(r, reason);                // 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;                }            }        } 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,                            Activity.DONT_FINISH_TASK_WITH_ACTIVITY);            } catch (RemoteException ex) {                throw ex.rethrowFromSystemServer();            }        }    }

其中 Activity a = performLaunchActivity(r, customIntent);

    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(                    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 (r.overrideConfig != null) {                    config.updateFrom(r.overrideConfig);                }                if (DEBUG_CONFIGURATION) Slog.v(TAG, "Launching activity "                        + r.activityInfo.name + " with config " + config);                Window window = null;                if (r.mPendingRemoveWindow != null && r.mPreserveWindow) {                    window = r.mPendingRemoveWindow;                    r.mPendingRemoveWindow = null;                    r.mPendingRemoveWindowManager = 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);                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);                } 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;    }

其中attach方法中生成PhoneWindow对象：

  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) {        attachBaseContext(context);        mFragments.attachHost(null /*parent*/);        mWindow = new PhoneWindow(this, window);        mWindow.setWindowControllerCallback(this);        mWindow.setCallback(this);        mWindow.setOnWindowDismissedCallback(this);        mWindow.getLayoutInflater().setPrivateFactory(this);        if (info.softInputMode != WindowManager.LayoutParams.SOFT_INPUT_STATE_UNSPECIFIED) {            mWindow.setSoftInputMode(info.softInputMode);        }        if (info.uiOptions != 0) {            mWindow.setUiOptions(info.uiOptions);        }        mUiThread = Thread.currentThread();        mMainThread = aThread;        mInstrumentation = instr;        mToken = token;        mIdent = ident;        mApplication = application;        mIntent = intent;        mReferrer = referrer;        mComponent = intent.getComponent();        mActivityInfo = info;        mTitle = title;        mParent = parent;        mEmbeddedID = id;        mLastNonConfigurationInstances = lastNonConfigurationInstances;        if (voiceInteractor != null) {            if (lastNonConfigurationInstances != null) {                mVoiceInteractor = lastNonConfigurationInstances.voiceInteractor;            } else {                mVoiceInteractor = new VoiceInteractor(voiceInteractor, this, this,                        Looper.myLooper());            }        }        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();        mCurrentConfig = config;    }

至此，PhoneWindow对象创建完成。

未完待续