StatusBar总结

简要说明:
该分析基于android 8.1.0

StatusBar的启动流程

1. systemservice ->main -> run -> startotherservice ->startsystemui -> startServiceAsUser()

// 启动systemService run方法
    public static void main(String[] args) {
        new SystemServer().run();
    }
private void run ( ) { 
....
// 启动服务
        try {
            traceBeginAndSlog("StartServices");
            startBootstrapServices();
            startCoreServices();
            startOtherServices();
            SystemServerInitThreadPool.shutdown();
        } catch (Throwable ex) {
            Slog.e("System", "******************************************");
            Slog.e("System", "************ Failure starting system services", ex);
            throw ex;
        } finally {
            traceEnd();
        }
}
private void startOtherService{
...
      traceBeginAndSlog("StartSystemUI");
            try {
                startSystemUi(context, windowManagerF);
            } catch (Throwable e) {
                reportWtf("starting System UI", e);
            }
            traceEnd();
...
}

static final void startSystemUi(Context context, WindowManagerService windowManager) {
        Intent intent = new Intent();
        intent.setComponent(new ComponentName("com.android.systemui",
                    "com.android.systemui.SystemUIService"));
        intent.addFlags(Intent.FLAG_DEBUG_TRIAGED_MISSING);
        //Slog.d(TAG, "Starting service: " + intent);
        context.startServiceAsUser(intent, UserHandle.SYSTEM);
        windowManager.onSystemUiStarted();
    }

2. 通过 startServiceAsUser 启动了SystemUIService
3. SystemUIService -> onCreate -> ((SystemUIApplication) getApplication()).startServicesIfNeeded()

public class SystemUIService extends Service {

    @Override
    public void onCreate() {
        super.onCreate();
        ((SystemUIApplication) getApplication()).startServicesIfNeeded();

        // For debugging RescueParty
        if (Build.IS_DEBUGGABLE && SystemProperties.getBoolean("debug.crash_sysui", false)) {
            throw new RuntimeException();
        }
    }
...
  }

4. 通过startServicesIfNeeded 启动SystemBars

    private final Class<?>[] SERVICES = new Class[] {
            Dependency.class,
            NotificationChannels.class,
            CommandQueue.CommandQueueStart.class,
            KeyguardViewMediator.class,
            Recents.class,
            VolumeUI.class,
            Divider.class,
            SystemBars.class,
            StorageNotification.class,
            PowerUI.class,
            RingtonePlayer.class,
            KeyboardUI.class,
            PipUI.class,
            ShortcutKeyDispatcher.class,
            VendorServices.class,
            GarbageMonitor.Service.class,
            LatencyTester.class,
            GlobalActionsComponent.class,
            RoundedCorners.class,
    };

private void startServicesIfNeeded(Class<?>[] services) {
        if (mServicesStarted) {
            return;
        }

        if (!mBootCompleted) {
            // check to see if maybe it was already completed long before we began
            // see ActivityManagerService.finishBooting()
            if ("1".equals(SystemProperties.get("sys.boot_completed"))) {
                mBootCompleted = true;
                if (DEBUG) Log.v(TAG, "BOOT_COMPLETED was already sent");
            }
        }

        Log.v(TAG, "Starting SystemUI services for user " +
                Process.myUserHandle().getIdentifier() + ".");
        TimingsTraceLog log = new TimingsTraceLog("SystemUIBootTiming",
                Trace.TRACE_TAG_APP);
        log.traceBegin("StartServices");
        final int N = services.length;
        for (int i = 0; i < N; i++) {
            Class<?> cl = services[i];
            if (DEBUG) Log.d(TAG, "loading: " + cl);
            log.traceBegin("StartServices" + cl.getSimpleName());
            long ti = System.currentTimeMillis();
            try {

================================启动service=================================================
                Object newService = SystemUIFactory.getInstance().createInstance(cl);
                mServices[i] = (SystemUI) ((newService == null) ? cl.newInstance() : newService);
            } catch (IllegalAccessException ex) {
                throw new RuntimeException(ex);
            } catch (InstantiationException ex) {
                throw new RuntimeException(ex);
            }

            mServices[i].mContext = this;
            mServices[i].mComponents = mComponents;
            if (DEBUG) Log.d(TAG, "running: " + mServices[i]);
            mServices[i].start();
            log.traceEnd();
===========================end=====================================
            // Warn if initialization of component takes too long
            ti = System.currentTimeMillis() - ti;
            if (ti > 1000) {
                Log.w(TAG, "Initialization of " + cl.getName() + " took " + ti + " ms");
            }
            if (mBootCompleted) {
                mServices[i].onBootCompleted();
            }
        }
        log.traceEnd();
        Dependency.get(PluginManager.class).addPluginListener(
                new PluginListener<OverlayPlugin>() {
                    private ArraySet<OverlayPlugin> mOverlays;

                    @Override
                    public void onPluginConnected(OverlayPlugin plugin, Context pluginContext) {
                        StatusBar statusBar = getComponent(StatusBar.class);
                        if (statusBar != null) {
                            plugin.setup(statusBar.getStatusBarWindow(),
                                    statusBar.getNavigationBarView());
                        }
                        // Lazy init.
                        if (mOverlays == null) mOverlays = new ArraySet<>();
                        if (plugin.holdStatusBarOpen()) {
                            mOverlays.add(plugin);
                            Dependency.get(StatusBarWindowManager.class).setStateListener(b ->
                                    mOverlays.forEach(o -> o.setCollapseDesired(b)));
                            Dependency.get(StatusBarWindowManager.class).setForcePluginOpen(
                                    mOverlays.size() != 0);

                        }
                    }

                    @Override
                    public void onPluginDisconnected(OverlayPlugin plugin) {
                        mOverlays.remove(plugin);
                        Dependency.get(StatusBarWindowManager.class).setForcePluginOpen(
                                mOverlays.size() != 0);
                    }
                }, OverlayPlugin.class, true /* Allow multiple plugins */);

        mServicesStarted = true;
    }

5. systembars -> start() -> createStatusBarFromConfig -> mStatusBar = (SystemUI) cls.newInstance()... mStatusBar.start();

public class SystemBars extends SystemUI{
...
private void createStatusBarFromConfig() {
        if (DEBUG) Log.d(TAG, "createStatusBarFromConfig");
        final String clsName = mContext.getString(R.string.config_statusBarComponent);
        if (clsName == null || clsName.length() == 0) {
            throw andLog("No status bar component configured", null);
        }
        Class<?> cls = null;
        try {
            cls = mContext.getClassLoader().loadClass(clsName);
        } catch (Throwable t) {
            throw andLog("Error loading status bar component: " + clsName, t);
        }
        try {
            mStatusBar = (SystemUI) cls.newInstance();
        } catch (Throwable t) {
            throw andLog("Error creating status bar component: " + clsName, t);
        }
        mStatusBar.mContext = mContext;
        mStatusBar.mComponents = mComponents;
        mStatusBar.start();
        if (DEBUG) Log.d(TAG, "started " + mStatusBar.getClass().getSimpleName());
    }
...
}

6. StatusBar -> start() -> createAndAddWindows() - > addStatusBarWindow() ->makeStatusBarView()

protected void makeStatusBarView() {
        final Context context = mContext;
        updateDisplaySize(); // populates mDisplayMetrics
        updateResources();
        updateTheme();

        inflateStatusBarWindow(context);
        mStatusBarWindow.setService(this);
        mStatusBarWindow.setOnTouchListener(getStatusBarWindowTouchListener());

        // TODO: Deal with the ugliness that comes from having some of the statusbar broken out
        // into fragments, but the rest here, it leaves some awkward lifecycle and whatnot.
        mNotificationPanel = (NotificationPanelView) mStatusBarWindow.findViewById(
                R.id.notification_panel);
        mStackScroller = (NotificationStackScrollLayout) mStatusBarWindow.findViewById(
                R.id.notification_stack_scroller);
        mNotificationPanel.setStatusBar(this);
        mNotificationPanel.setGroupManager(mGroupManager);
        mAboveShelfObserver = new AboveShelfObserver(mStackScroller);
        mAboveShelfObserver.setListener(mStatusBarWindow.findViewById(
                R.id.notification_container_parent));
        mKeyguardStatusBar = (KeyguardStatusBarView) mStatusBarWindow.findViewById(R.id.keyguard_header);

        mNotificationIconAreaController = SystemUIFactory.getInstance()
                .createNotificationIconAreaController(context, this);
        inflateShelf();
        mNotificationIconAreaController.setupShelf(mNotificationShelf);
        Dependency.get(DarkIconDispatcher.class).addDarkReceiver(mNotificationIconAreaController);
        FragmentHostManager.get(mStatusBarWindow)
                .addTagListener(CollapsedStatusBarFragment.TAG, (tag, fragment) -> {
                    CollapsedStatusBarFragment statusBarFragment =
                            (CollapsedStatusBarFragment) fragment;
                    statusBarFragment.initNotificationIconArea(mNotificationIconAreaController);
                    mStatusBarView = (PhoneStatusBarView) fragment.getView();
                    mStatusBarView.setBar(this);
                    mStatusBarView.setPanel(mNotificationPanel);
                    mStatusBarView.setScrimController(mScrimController);
                    mStatusBarView.setBouncerShowing(mBouncerShowing);
                    setAreThereNotifications();
                    checkBarModes();
                }).getFragmentManager()
                .beginTransaction()
                .replace(R.id.status_bar_container, new CollapsedStatusBarFragment(),
                        CollapsedStatusBarFragment.TAG)
                .commit();
        mIconController = Dependency.get(StatusBarIconController.class);

        mHeadsUpManager = new HeadsUpManager(context, mStatusBarWindow, mGroupManager);
        mHeadsUpManager.setBar(this);
        mHeadsUpManager.addListener(this);
        mHeadsUpManager.addListener(mNotificationPanel);
        mHeadsUpManager.addListener(mGroupManager);
        mHeadsUpManager.addListener(mVisualStabilityManager);
        mNotificationPanel.setHeadsUpManager(mHeadsUpManager);
        mNotificationData.setHeadsUpManager(mHeadsUpManager);
        mGroupManager.setHeadsUpManager(mHeadsUpManager);
        mHeadsUpManager.setVisualStabilityManager(mVisualStabilityManager);

        if (MULTIUSER_DEBUG) {
            mNotificationPanelDebugText = (TextView) mNotificationPanel.findViewById(
                    R.id.header_debug_info);
            mNotificationPanelDebugText.setVisibility(View.VISIBLE);
        }

        try {
            boolean showNav = mWindowManagerService.hasNavigationBar();
            if (DEBUG) Log.v(TAG, "hasNavigationBar=" + showNav);
            if (showNav) {
                createNavigationBar();
            }
        } catch (RemoteException ex) {
            // no window manager? good luck with that
        }

        // figure out which pixel-format to use for the status bar.
        mPixelFormat = PixelFormat.OPAQUE;

        mStackScroller.setLongPressListener(getNotificationLongClicker());
        mStackScroller.setStatusBar(this);
        mStackScroller.setGroupManager(mGroupManager);
        mStackScroller.setHeadsUpManager(mHeadsUpManager);
        mGroupManager.setOnGroupChangeListener(mStackScroller);
        mVisualStabilityManager.setVisibilityLocationProvider(mStackScroller);

        inflateEmptyShadeView();
        inflateDismissView();
        mExpandedContents = mStackScroller;

        mBackdrop = (BackDropView) mStatusBarWindow.findViewById(R.id.backdrop);
        mBackdropFront = (ImageView) mBackdrop.findViewById(R.id.backdrop_front);
        mBackdropBack = (ImageView) mBackdrop.findViewById(R.id.backdrop_back);

        if (ENABLE_LOCKSCREEN_WALLPAPER) {
            mLockscreenWallpaper = new LockscreenWallpaper(mContext, this, mHandler);
        }

        mKeyguardIndicationController =
                SystemUIFactory.getInstance().createKeyguardIndicationController(mContext,
                (ViewGroup) mStatusBarWindow.findViewById(R.id.keyguard_indication_area),
                mNotificationPanel.getLockIcon());
        mNotificationPanel.setKeyguardIndicationController(mKeyguardIndicationController);


        mAmbientIndicationContainer = mStatusBarWindow.findViewById(
                R.id.ambient_indication_container);

        // set the initial view visibility
        setAreThereNotifications();

        // TODO: Find better place for this callback.
        mBatteryController.addCallback(new BatteryStateChangeCallback() {
            @Override
            public void onPowerSaveChanged(boolean isPowerSave) {
                mHandler.post(mCheckBarModes);
                if (mDozeServiceHost != null) {
                    mDozeServiceHost.firePowerSaveChanged(isPowerSave);
                }
            }

            @Override
            public void onBatteryLevelChanged(int level, boolean pluggedIn, boolean charging) {
                // noop
            }
        });

        mLightBarController = Dependency.get(LightBarController.class);
        if (mNavigationBar != null) {
            mNavigationBar.setLightBarController(mLightBarController);
        }

        ScrimView scrimBehind = (ScrimView) mStatusBarWindow.findViewById(R.id.scrim_behind);
        ScrimView scrimInFront = (ScrimView) mStatusBarWindow.findViewById(R.id.scrim_in_front);
        View headsUpScrim = mStatusBarWindow.findViewById(R.id.heads_up_scrim);
        mScrimController = SystemUIFactory.getInstance().createScrimController(mLightBarController,
                scrimBehind, scrimInFront, headsUpScrim, mLockscreenWallpaper,
                scrimsVisible -> {
                    if (mStatusBarWindowManager != null) {
                        mStatusBarWindowManager.setScrimsVisible(scrimsVisible);
                    }
                });
        if (mScrimSrcModeEnabled) {
            Runnable runnable = new Runnable() {
                @Override
                public void run() {
                    boolean asSrc = mBackdrop.getVisibility() != View.VISIBLE;
                    mScrimController.setDrawBehindAsSrc(asSrc);
                    mStackScroller.setDrawBackgroundAsSrc(asSrc);
                }
            };
            mBackdrop.setOnVisibilityChangedRunnable(runnable);
            runnable.run();
        }
        mHeadsUpManager.addListener(mScrimController);
        mStackScroller.setScrimController(mScrimController);
        mDozeScrimController = new DozeScrimController(mScrimController, context);

        // Other icons
        mVolumeComponent = getComponent(VolumeComponent.class);

        mNotificationPanel.setUserSetupComplete(mUserSetup);
        if (UserManager.get(mContext).isUserSwitcherEnabled()) {
            createUserSwitcher();
        }

        // Set up the quick settings tile panel
        View container = mStatusBarWindow.findViewById(R.id.qs_frame);
        if (container != null) {
            FragmentHostManager fragmentHostManager = FragmentHostManager.get(container);
            ExtensionFragmentListener.attachExtensonToFragment(container, QS.TAG, R.id.qs_frame,
                    Dependency.get(ExtensionController.class).newExtension(QS.class)
                            .withPlugin(QS.class)
                            .withFeature(
                                    PackageManager.FEATURE_AUTOMOTIVE, () -> new CarQSFragment())
                            .withDefault(() -> new QSFragment())
                            .build());
            final QSTileHost qsh = SystemUIFactory.getInstance().createQSTileHost(mContext, this,
                    mIconController);
            mBrightnessMirrorController = new BrightnessMirrorController(mStatusBarWindow,
                    mScrimController);
            fragmentHostManager.addTagListener(QS.TAG, (tag, f) -> {
                QS qs = (QS) f;
                if (qs instanceof QSFragment) {
                    ((QSFragment) qs).setHost(qsh);
                    mQSPanel = ((QSFragment) qs).getQsPanel();
                    mQSPanel.setBrightnessMirror(mBrightnessMirrorController);
                    mKeyguardStatusBar.setQSPanel(mQSPanel);
                }
            });
        }

        mReportRejectedTouch = mStatusBarWindow.findViewById(R.id.report_rejected_touch);
        if (mReportRejectedTouch != null) {
            updateReportRejectedTouchVisibility();
            mReportRejectedTouch.setOnClickListener(v -> {
                Uri session = mFalsingManager.reportRejectedTouch();
                if (session == null) { return; }

                StringWriter message = new StringWriter();
                message.write("Build info: ");
                message.write(SystemProperties.get("ro.build.description"));
                message.write("\nSerial number: ");
                message.write(SystemProperties.get("ro.serialno"));
                message.write("\n");

                PrintWriter falsingPw = new PrintWriter(message);
                FalsingLog.dump(falsingPw);
                falsingPw.flush();

                startActivityDismissingKeyguard(Intent.createChooser(new Intent(Intent.ACTION_SEND)
                                .setType("*/*")
                                .putExtra(Intent.EXTRA_SUBJECT, "Rejected touch report")
                                .putExtra(Intent.EXTRA_STREAM, session)
                                .putExtra(Intent.EXTRA_TEXT, message.toString()),
                        "Share rejected touch report")
                                .addFlags(Intent.FLAG_ACTIVITY_NEW_TASK),
                        true /* onlyProvisioned */, true /* dismissShade */);
            });
        }

        PowerManager pm = (PowerManager) mContext.getSystemService(Context.POWER_SERVICE);
        if (!pm.isScreenOn()) {
            mBroadcastReceiver.onReceive(mContext, new Intent(Intent.ACTION_SCREEN_OFF));
        }
        mGestureWakeLock = pm.newWakeLock(PowerManager.SCREEN_BRIGHT_WAKE_LOCK,
                "GestureWakeLock");
        mVibrator = mContext.getSystemService(Vibrator.class);
        int[] pattern = mContext.getResources().getIntArray(
                R.array.config_cameraLaunchGestureVibePattern);
        mCameraLaunchGestureVibePattern = new long[pattern.length];
        for (int i = 0; i < pattern.length; i++) {
            mCameraLaunchGestureVibePattern[i] = pattern[i];
        }

        // receive broadcasts
        IntentFilter filter = new IntentFilter();
        filter.addAction(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
        filter.addAction(Intent.ACTION_SCREEN_OFF);
        filter.addAction(DevicePolicyManager.ACTION_SHOW_DEVICE_MONITORING_DIALOG);
        context.registerReceiverAsUser(mBroadcastReceiver, UserHandle.ALL, filter, null, null);

        IntentFilter demoFilter = new IntentFilter();
        if (DEBUG_MEDIA_FAKE_ARTWORK) {
            demoFilter.addAction(ACTION_FAKE_ARTWORK);
        }
        demoFilter.addAction(ACTION_DEMO);
        context.registerReceiverAsUser(mDemoReceiver, UserHandle.ALL, demoFilter,
                android.Manifest.permission.DUMP, null);

        // listen for USER_SETUP_COMPLETE setting (per-user)
        mDeviceProvisionedController.addCallback(mUserSetupObserver);
        mUserSetupObserver.onUserSetupChanged();

        // disable profiling bars, since they overlap and clutter the output on app windows
        ThreadedRenderer.overrideProperty("disableProfileBars", "true");

        // Private API call to make the shadows look better for Recents
        ThreadedRenderer.overrideProperty("ambientRatio", String.valueOf(1.5f));
    }

makeStatusBarView()
6.1: 找到 mNotificationPanel
6.2: 找到 NotificationStackScrollLayout
6.3: 找到KeyguardStatusBarView
6.4: 创建NotificationIconAreaController
6.5: 找到KeyguardIndicationController
6.6: createNavigationBar();
....

Notification

1. NotificationManager -> notify -> notifyAsUser() -> enqueueNotificationWithTag(说明调用者: INotificationManager)

aidl默认调用NotificationManagerService

2. NotificationManagerService -> enqueueNotificationWithTag() -> enqueueNotificationInternal()

post(new EnqueueNotificationRunnable(userid, r)); 将Notification发送到EnqueueNotificationRunnable 处理

3. EnqueueNotificationRunnable -> run() -> PostNotificationRunnable-> run

调用 NotificationManagerService.NotificationManager 的 notifyRemovedLocked

4. NotificationManagerService.NotificationManager -> notifyPosted() -> listener.onNotificationPosted(sbnHolder, rankingUpdate);

5. PopupDataProvider -> onNotificationPosted -> updateLauncherIconBadges -> updateNotificationHeader -> updateNotificationHeader -> mNotificationItemView.updateHeader(badgeInfo.getNotificationCount(), palette);

6. NotificationItemView -> updateHeader

NavigationBar

1. StatusBar -> start() -> createAndWindows() ->addStatusBarWindow() -> makeStatusBarView() -> createNavigationBar()

protected void createNavigationBar() {
       mNavigationBarView = NavigationBarFragment.create(mContext, (tag, fragment) -> {
           mNavigationBar = (NavigationBarFragment) fragment;
           if (mLightBarController != null) {
               mNavigationBar.setLightBarController(mLightBarController);
           }
           mNavigationBar.setCurrentSysuiVisibility(mSystemUiVisibility);
       });
   }

KeyGuard

1. StatusBar -> start() -> startKeyguard() -> keyguardViewMediator.registerStatusBar
2. KeyguradViewMediator -> registerStatusBar
3. StatusBarKeyguardViewManager ->registerStatusBar -> SystemUIFactory.getInstance().createKeyguardBouncer
4. SystemUIFactory -> createKeyguardBouncer

// mContainer (viewGroup) 其实是 StatusBarWindowView的对象

5. KeyguardBouncer -> inflateView -> mContainer.addView(mRoot, mContainer.getChildCount())

 KeyguardBouncer 部分核心源码:
public KeyguardBouncer(Context context, ViewMediatorCallback callback,
            LockPatternUtils lockPatternUtils, ViewGroup container,
            DismissCallbackRegistry dismissCallbackRegistry) {
        mContext = context;
        mCallback = callback;
        mLockPatternUtils = lockPatternUtils;
        mContainer = container;
        KeyguardUpdateMonitor.getInstance(mContext).registerCallback(mUpdateMonitorCallback);
        mFalsingManager = FalsingManager.getInstance(mContext);
        mDismissCallbackRegistry = dismissCallbackRegistry;
        mHandler = new Handler();
    }

    public void show(boolean resetSecuritySelection) {
        final int keyguardUserId = KeyguardUpdateMonitor.getCurrentUser();
        if (keyguardUserId == UserHandle.USER_SYSTEM && UserManager.isSplitSystemUser()) {
            // In split system user mode, we never unlock system user.
            return;
        }
        mFalsingManager.onBouncerShown();
        ensureView();
        if (resetSecuritySelection) {
            // showPrimarySecurityScreen() updates the current security method. This is needed in
            // case we are already showing and the current security method changed.
            mKeyguardView.showPrimarySecurityScreen();
        }
        if (mRoot.getVisibility() == View.VISIBLE || mShowingSoon) {
            return;
        }

        final int activeUserId = ActivityManager.getCurrentUser();
        final boolean isSystemUser =
                UserManager.isSplitSystemUser() && activeUserId == UserHandle.USER_SYSTEM;
        final boolean allowDismissKeyguard = !isSystemUser && activeUserId == keyguardUserId;

        // If allowed, try to dismiss the Keyguard. If no security auth (password/pin/pattern) is
        // set, this will dismiss the whole Keyguard. Otherwise, show the bouncer.
        if (allowDismissKeyguard && mKeyguardView.dismiss(activeUserId)) {
            return;
        }

        // This condition may indicate an error on Android, so log it.
        if (!allowDismissKeyguard) {
            Slog.w(TAG, "User can't dismiss keyguard: " + activeUserId + " != " + keyguardUserId);
        }

        mShowingSoon = true;

        // Split up the work over multiple frames.
        DejankUtils.postAfterTraversal(mShowRunnable);
    }
protected void inflateView() {
        removeView();
        mHandler.removeCallbacks(mRemoveViewRunnable);
        mRoot = (ViewGroup) LayoutInflater.from(mContext).inflate(R.layout.keyguard_bouncer, null);
        mKeyguardView = mRoot.findViewById(R.id.keyguard_host_view);
        mKeyguardView.setLockPatternUtils(mLockPatternUtils);
        mKeyguardView.setViewMediatorCallback(mCallback);
        mContainer.addView(mRoot, mContainer.getChildCount());
        mStatusBarHeight = mRoot.getResources().getDimensionPixelOffset(
                com.android.systemui.R.dimen.status_bar_height);
        mRoot.setVisibility(View.INVISIBLE);

        final WindowInsets rootInsets = mRoot.getRootWindowInsets();
        if (rootInsets != null) {
            mRoot.dispatchApplyWindowInsets(rootInsets);
        }
    }