【用来参考】AndroidQ SystemUI之锁屏加载（上）滑动锁屏
原文地址：AndroidQ SystemUI之锁屏加载（上）滑动锁屏
原文格式我个人感觉看着不是很顺，所以稍微调整下，便于我自己阅读理解。
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本篇来分析下Android锁屏的加载流程，锁屏加载比较复杂，涉及framework和SystemUI，这篇主要分析SystemUI部分，锁屏有两种，一种滑动锁屏，另一种密码锁屏，也叫Bouncer。
前面AndroidQ SystemUI之启动 中分析了SystemUI启动过程中会加载一个config数组，里面定义了SystemUI的重要的类，之后遍历此数组，以此调用其Start方法，我们就从StatusBar.start方法开始分析锁屏相关的流程
StatusBar.start
public void start() {
…
createAndAddWindows(result);
…
}
public void createAndAddWindows(@Nullable RegisterStatusBarResult result) {
makeStatusBarView(result);
mStatusBarWindowController = Dependency.get(StatusBarWindowController.class);
mStatusBarWindowController.add(mStatusBarWindow, getStatusBarHeight());
}
makeStatusBarView方法里面会初始化很多SystemUI的View
makeStatusBarView
protected void makeStatusBarView(@Nullable RegisterStatusBarResult result) {
...
inflateStatusBarWindow(context);
...
}
inflateStatusBarWindow
protected void inflateStatusBarWindow(Context context) {
mStatusBarWindow = (StatusBarWindowView) mInjectionInflater.injectable(
LayoutInflater.from(context)).inflate(R.layout.super_status_bar, null);
}
这个方法，加载了整个StatusBar的顶层自定义布局，类型为StatusBarWindowView，继承FrameLayout，布局文件是super_status_bar.xml，
<com.android.systemui.statusbar.phone.StatusBarWindowView
xmlns:android=“http://schemas.android.com/apk/res/android”
xmlns:sysui=“http://schemas.android.com/apk/res-auto”
android:layout_width=“match_parent”
android:layout_height=“match_parent”
android:background="#698541"
android:fitsSystemWindows=“true”>
<com.android.systemui.statusbar.BackDropView
android:id="@+id/backdrop"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone"
sysui:ignoreRightInset="true"
>
<ImageView android:id="@+id/backdrop_back"
android:layout_width="match_parent"
android:scaleType="centerCrop"
android:layout_height="match_parent" />
<ImageView android:id="@+id/backdrop_front"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:scaleType="centerCrop"
android:visibility="invisible" />
</com.android.systemui.statusbar.BackDropView>
<com.android.systemui.statusbar.ScrimView
android:id="@+id/scrim_behind"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:importantForAccessibility="no"
sysui:ignoreRightInset="true"
/>
<FrameLayout
android:id="@+id/status_bar_container"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
<include layout="@layout/status_bar_expanded"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="invisible" />
<include layout="@layout/brightness_mirror" />
<com.android.systemui.statusbar.ScrimView
android:id="@+id/scrim_in_front"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:importantForAccessibility="no"
sysui:ignoreRightInset="true"
/>
<LinearLayout
android:id="@+id/lock_icon_container"
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/status_bar_height"
android:layout_gravity="top|center_horizontal">
<com.android.systemui.statusbar.phone.LockIcon
android:id="@+id/lock_icon"
android:layout_width="@dimen/keyguard_lock_padding"
android:contentDescription="@string/accessibility_unlock_button"
android:src="@*android:drawable/ic_lock"
android:scaleType="center" />
<com.android.keyguard.KeyguardMessageArea
android:id="@+id/keyguard_message_area"
style="@style/Keyguard.TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="@dimen/keyguard_lock_padding"
android:gravity="center"
android:singleLine="true"
android:ellipsize="marquee"
android:focusable="true" />
</LinearLayout>
</com.android.systemui.statusbar.phone.StatusBarWindowView>
接着我们看下StatusBarWindowView的onFinishInflate方法
onFinishInflate
@Override
protected void onFinishInflate() {
super.onFinishInflate();
mStackScrollLayout = findViewById(R.id.notification_stack_scroller);
mNotificationPanel = findViewById(R.id.notification_panel);
mBrightnessMirror = findViewById(R.id.brightness_mirror);
mLockIcon = findViewById(R.id.lock_icon);
}
这里分别加载了id为notification_stack_scroller，notification_panel，brightness_mirror，lock_icon的View，
notification_stack_scroller是锁屏上承载notification的View
notification_panel是滑动锁屏
brightness_mirror是调节亮度条的View
lock_icon是锁屏上的那个锁一样的View
再回到makeStatusBarView方法
protected void makeStatusBarView(@Nullable RegisterStatusBarResult result) {
...
//此方法已经完成StatusBar顶层View，已经滑动锁屏相关View的加载
inflateStatusBarWindow(context);
//获取滑动锁屏的View
mNotificationPanel = mStatusBarWindow.findViewById(R.id.notification_panel);
//获取锁屏上承载通知的View
mStackScroller = mStatusBarWindow.findViewById(R.id.notification_stack_scroller);
...
}
makeStatusBarView方法中获取到了滑动锁屏的View，再回到createAndAddWindows
public void createAndAddWindows(@Nullable RegisterStatusBarResult result) {
makeStatusBarView(result);
mStatusBarWindowController = Dependency.get(StatusBarWindowController.class);
mStatusBarWindowController.add(mStatusBarWindow, getStatusBarHeight());
}
mStatusBarWindowController.add
下面代码很明显了，通过mWindowManager添加了一个窗口，这样SystemUI的顶层自定义ViewGroup就被添加到了WMS，自然，滑动锁屏作为mStatusBarWindow的子View也就被添加了
public void add(ViewGroup statusBarView, int barHeight) {
//创建LayoutParams，定义了一些窗口属性
mLp = new WindowManager.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
barHeight,
WindowManager.LayoutParams.TYPE_STATUS_BAR,
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE
| WindowManager.LayoutParams.FLAG_TOUCHABLE_WHEN_WAKING
| WindowManager.LayoutParams.FLAG_SPLIT_TOUCH
| WindowManager.LayoutParams.FLAG_WATCH_OUTSIDE_TOUCH
| WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS,
PixelFormat.TRANSLUCENT);
//创建Token
mLp.token = new Binder();
//位置在最顶部
mLp.gravity = Gravity.TOP;
mLp.softInputMode = WindowManager.LayoutParams.SOFT_INPUT_ADJUST_RESIZE;
mLp.setTitle("StatusBar");
mLp.packageName = mContext.getPackageName();
mLp.layoutInDisplayCutoutMode = LAYOUT_IN_DISPLAY_CUTOUT_MODE_ALWAYS;
mStatusBarView = statusBarView;
mBarHeight = barHeight;
//添加到WMS
mWindowManager.addView(mStatusBarView, mLp);
mLpChanged.copyFrom(mLp);
onThemeChanged();
}
我们会发现密码锁屏并不是直接写死在xml文件中的，密码锁屏是通过动态加载的，我们接下来分析密码锁屏是如何创建以及添加到Keyguard布局中的
回到最开始的StatusBar的start方法中，在调用createAndAddWindows加载完SyatemUI相关View之后接着会调用startKeyguard方法开启锁屏流程
public void start() {
...
createAndAddWindows(result);
...
startKeyguard();
}
startKeyguard
protected void startKeyguard() {
KeyguardViewMediator keyguardViewMediator = getComponent(KeyguardViewMediator.class);
...
mStatusBarKeyguardViewManager = keyguardViewMediator.registerStatusBar(this,
getBouncerContainer(), mNotificationPanel, mBiometricUnlockController,
mStatusBarWindow.findViewById(R.id.lock_icon_container));
...
}
首先获取了一个锁屏非常重要的类KeyguardViewMediator，这个类主要负责处理锁屏相关事务，接着调用registerStatusBar方法，这里传了一个getBouncerContainer()的ViewGroup过去，这个ViewGroup就是StartBar中加载的SystemUI最顶层ViewGroup，布局为super_status_bar的StatusBarWindowView，后面创建的密码锁屏会动态添加到这里面
keyguardViewMediator.registerStatusBar
public StatusBarKeyguardViewManager registerStatusBar(StatusBar statusBar,
ViewGroup container, NotificationPanelView panelView,
BiometricUnlockController biometricUnlockController, ViewGroup lockIconContainer) {
mStatusBarKeyguardViewManager.registerStatusBar(statusBar, container, panelView,
biometricUnlockController, mDismissCallbackRegistry, lockIconContainer);
return mStatusBarKeyguardViewManager;
}
接着调用
StatusBarKeyguardViewManager.registerStatusBar
public void registerStatusBar(StatusBar statusBar,
ViewGroup container,
NotificationPanelView notificationPanelView,
BiometricUnlockController biometricUnlockController,
DismissCallbackRegistry dismissCallbackRegistry,
ViewGroup lockIconContainer) {
mStatusBar = statusBar;
//StatusBar传递过来的SystemUI顶层ViewGroup
mContainer = container;
//锁屏上承载lockIcon的ViewGroup
mLockIconContainer = lockIconContainer;
if (mLockIconContainer != null) {
mLastLockVisible = mLockIconContainer.getVisibility() == View.VISIBLE;
}
//生物识别相关
mBiometricUnlockController = biometricUnlockController;
//创建密码锁屏Bouncer
mBouncer = SystemUIFactory.getInstance().createKeyguardBouncer(mContext,
mViewMediatorCallback, mLockPatternUtils, container, dismissCallbackRegistry,
mExpansionCallback);
mNotificationPanelView = notificationPanelView;
//给滑动锁屏界面设置监听器
notificationPanelView.setExpansionListener(this);
}
来看看Bouncer的创建
SystemUIFactory.createKeyguardBouncer
public KeyguardBouncer createKeyguardBouncer(Context context, ViewMediatorCallback callback,
LockPatternUtils lockPatternUtils, ViewGroup container,
DismissCallbackRegistry dismissCallbackRegistry,
KeyguardBouncer.BouncerExpansionCallback expansionCallback) {
return new KeyguardBouncer(context, callback, lockPatternUtils, container,
dismissCallbackRegistry, FalsingManagerFactory.getInstance(context),
expansionCallback, KeyguardUpdateMonitor.getInstance(context),
new Handler(Looper.getMainLooper()));
}
这里直接new了一个Bouncer对象，我们跟进KeyguardBouncer这个类会发现它并没有继承View或者ViewGroup，说明它并不是真正的密码锁屏的View，KeyguardBouncer其实是用来管理密码锁屏的，从它提供的方法就能看出来，show，hide，inflateView等
public class KeyguardBouncer {
public KeyguardBouncer(Context context, ViewMediatorCallback callback,
LockPatternUtils lockPatternUtils, ViewGroup container,
DismissCallbackRegistry dismissCallbackRegistry, FalsingManager falsingManager,
BouncerExpansionCallback expansionCallback,
KeyguardUpdateMonitor keyguardUpdateMonitor, Handler handler) {
mContext = context;
mCallback = callback;
mLockPatternUtils = lockPatternUtils;
mContainer = container;
mKeyguardUpdateMonitor = keyguardUpdateMonitor;
mFalsingManager = falsingManager;
mDismissCallbackRegistry = dismissCallbackRegistry;
mExpansionCallback = expansionCallback;
mHandler = handler;
mKeyguardUpdateMonitor.registerCallback(mUpdateMonitorCallback);
}
}
到这里我们发现从StatusBar.start->StatusBar.startKeyguard->KeyguardViewMediator.registerStatusBar->StatusBarKeyguardViewManager.registerStatusBar->SystemUIFactory.createKeyguardBouncer->new KeyguardBouncer
在KeyguardBouncer构造方法中也只是做了些初始化，并没有涉及到和密码锁屏的创建及添加相关的操作
其实不管是滑动锁屏还是密码锁屏加载都是通过KeyguardViewMediator中的doKeyguardLocked方法，此方法非常重要，可以说是整个锁屏的核心方法，任何形式的锁屏，开机启动锁屏，点击power键锁屏，SIM卡状态变化锁屏都会调用此方法，我们就从此方法为入口分析锁屏加载流程
KeyguardViewMediator.doKeyguardLocked
private void doKeyguardLocked(Bundle options) {
//省略一些不需要加载锁屏的情况，如外部禁用，系统没准备好等
....
showLocked(options);
}
private void showLocked(Bundle options) {
mShowKeyguardWakeLock.acquire();
Message msg = mHandler.obtainMessage(SHOW, options);
mHandler.sendMessage(msg);
}
通过Handler发送消息
private Handler mHandler = new Handler(Looper.myLooper(), null, true /*async*/) {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case SHOW:
handleShow((Bundle) msg.obj);
break;
调用handleShow方法
private void handleShow(Bundle options) {
....
mStatusBarKeyguardViewManager.show(options);
....
}
StatusBarKeyguardViewManager.show
public void show(Bundle options) {
mShowing = true;
....
reset(true /* hideBouncerWhenShowing */);
}
reset
public void reset(boolean hideBouncerWhenShowing) {
if (mShowing) {
//不需要显示锁屏的情况
if (mOccluded && !mDozing) {
...
} else {
showBouncerOrKeyguard(hideBouncerWhenShowing);
}
...
}
}
接着调用showBouncerOrKeyguard方法，此方法中就是判断显示滑动锁屏，还是显示密码锁屏，参数hideBouncerWhenShowing代表是否隐藏Bouncer
showBouncerOrKeyguard
protected void showBouncerOrKeyguard(boolean hideBouncerWhenShowing) {
if (mBouncer.needsFullscreenBouncer() && !mDozing) {
//隐藏滑动锁屏
mStatusBar.hideKeyguard();
//显示密码锁屏
mBouncer.show(true /* resetSecuritySelection */);
} else {
//显示滑动锁屏
mStatusBar.showKeyguard();
if (hideBouncerWhenShowing) {
hideBouncer(shouldDestroyViewOnReset() /* destroyView */);
mBouncer.prepare();
}
}
updateStates();
}
什么情况下会直接显示密码锁屏界面呢？
KeyguardBouncer.needsFullscreenBouncer
public boolean needsFullscreenBouncer() {
ensureView();
if (mKeyguardView != null) {
SecurityMode mode = mKeyguardView.getSecurityMode();
return mode == SecurityMode.SimPin || mode == SecurityMode.SimPuk;
}
return false;
}
当前获取的Bouncer的类型是SimPin或者SimPuk时，通过mKeyguardView.getSecurityMode()获取当前Bouncer的类型时最终是调到KeyguardSecurityModel的getSecurityMode方法，通过KeyguardUpdateMonitor这个类获取当前SIM卡的状态来判断的，当状态是PIN_REQUIRED或者PUK_REQUIRED则说明应该直接显示类型为SecurityMode.SimPin或者SecurityMode.SimPuk的密码锁屏，所以当我们插入一张带密码的SIM卡时会立即显示sim pin界面
if (mIsPukScreenAvailable && SubscriptionManager.isValidSubscriptionId(
monitor.getNextSubIdForState(IccCardConstants.State.PUK_REQUIRED))) {
return SecurityMode.SimPuk;
}
if (SubscriptionManager.isValidSubscriptionId(
monitor.getNextSubIdForState(IccCardConstants.State.PIN_REQUIRED))) {
return SecurityMode.SimPin;
}
我们再来看看needsFullscreenBouncer中调用的ensureView方法
protected void ensureView() {
...
//首次调用mRoot为空
if (mRoot == null || forceRemoval) {
inflateView();
}
}
inflateView
protected void inflateView() {
//在初始化View之前先移除，以保持干净
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);
mRoot.setAccessibilityPaneTitle(mKeyguardView.getAccessibilityTitleForCurrentMode());
final WindowInsets rootInsets = mRoot.getRootWindowInsets();
if (rootInsets != null) {
mRoot.dispatchApplyWindowInsets(rootInsets);
}
}
此方法代码很明显，就是加载布局，加载View，然后addView，mRoot是名为keyguard_bouncer的layout，这是Bouncer的根布局
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@android:color/black"
android:fitsSystemWindows="true">
<include
style="@style/BouncerSecurityContainer"
layout="@layout/keyguard_host_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</FrameLayout>
这里面直接include了一个名为keyguard_host_view的layout，KeyguardHostView是一个自定义ViewGroup，里面包含KeyguardSecurityContainer，KeyguardSecurityContainer立马包含KeyguardSecurityViewFlipper
<com.android.keyguard.KeyguardHostView
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:androidprv="http://schemas.android.com/apk/res-auto"
android:id="@+id/keyguard_host_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false"
android:clipToPadding="false"
android:importantForAccessibility="yes"> <!-- Needed because TYPE_WINDOW_STATE_CHANGED is sent
from this view when bouncer is shown -->
<com.android.keyguard.KeyguardSecurityContainer
android:id="@+id/keyguard_security_container"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
androidprv:layout_maxHeight="@dimen/keyguard_security_max_height"
android:clipChildren="false"
android:clipToPadding="false"
android:padding="0dp"
android:fitsSystemWindows="true"
android:layout_gravity="center">
<com.android.keyguard.KeyguardSecurityViewFlipper
android:id="@+id/view_flipper"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:clipChildren="false"
android:clipToPadding="false"
android:paddingTop="@dimen/keyguard_security_view_top_margin"
android:paddingStart="@dimen/keyguard_security_view_lateral_margin"
android:paddingEnd="@dimen/keyguard_security_view_lateral_margin"
android:gravity="center">
</com.android.keyguard.KeyguardSecurityViewFlipper>
</com.android.keyguard.KeyguardSecurityContainer>
</com.android.keyguard.KeyguardHostView>
接着通过addView将mRoot添加到mContainer，mContainer我们前面有分析过，它是StatusBar传递过来的SystemUI顶层ViewGroup，接着mRoot.setVisibility(View.INVISIBLE)让mRoot暂时不可见
ensureView分析完了，此方法也只是初始化一些layout
接着再回到showBouncerOrKeyguard中去
showBouncerOrKeyguard
protected void showBouncerOrKeyguard(boolean hideBouncerWhenShowing) {
if (mBouncer.needsFullscreenBouncer() && !mDozing) {
mStatusBar.hideKeyguard();
mBouncer.show(true /* resetSecuritySelection */);
} else {
mStatusBar.showKeyguard();
if (hideBouncerWhenShowing) {
hideBouncer(shouldDestroyViewOnReset() /* destroyView */);
mBouncer.prepare();
}
}
updateStates();
}
我们分析了直接显示Bouncer的情况，是在SIM卡状态为PIN_REQUIRED或者PUK_REQUIRED时，如果是普通情况则会调用StatusBar.showKeyguard显示滑动锁屏
StatusBar.showKeyguard
public void showKeyguard() {
...
updateIsKeyguard();
...
}
updateIsKeyguard
private boolean updateIsKeyguard() {
...
boolean shouldBeKeyguard = (mStatusBarStateController.isKeyguardRequested()
|| keyguardForDozing) && !wakeAndUnlocking;
if (shouldBeKeyguard) {
if (isGoingToSleep()
&& mScreenLifecycle.getScreenState() == ScreenLifecycle.SCREEN_TURNING_OFF) {
// Delay showing the keyguard until screen turned off.
} else {
showKeyguardImpl();
}
} else {
return hideKeyguardImpl();
}
return false;
}
满足显示Keyguard的条件shouldBeKeyguard则调用showKeyguardImpl
showKeyguardImpl
public void showKeyguardImpl() {
...
updatePanelExpansionForKeyguard();
...
}
}
updatePanelExpansionForKeyguard
private void updatePanelExpansionForKeyguard() {
//状态为KEYGUARD，不是MODE_WAKE_AND_UNLOCK模式，不显示Bouncer
if (mState == StatusBarState.KEYGUARD && mBiometricUnlockController.getMode()
!= BiometricUnlockController.MODE_WAKE_AND_UNLOCK && !mBouncerShowing) {
instantExpandNotificationsPanel();
} else if (mState == StatusBarState.FULLSCREEN_USER_SWITCHER) {
instantCollapseNotificationPanel();
}
}
instantExpandNotificationsPanel
@Override
public void instantExpandNotificationsPanel() {
makeExpandedVisible(true);
//展开滑动锁屏
mNotificationPanel.expand(false /* animate */);
}
makeExpandedVisible
void makeExpandedVisible(boolean force) {
...
mStatusBarWindowController.setPanelVisible(true);
...
}
StatusBarWindowController.setPanelVisible
public void setPanelVisible(boolean visible) {
...
apply(mCurrentState);
}
apply
private void apply(State state) {
applyKeyguardFlags(state);
applyForceStatusBarVisibleFlag(state);
applyFocusableFlag(state);
applyForceShowNavigationFlag(state);
adjustScreenOrientation(state);
applyHeight(state);
applyUserActivityTimeout(state);
applyInputFeatures(state);
applyFitsSystemWindows(state);
applyModalFlag(state);
applyBrightness(state);
applyHasTopUi(state);
applyNotTouchable(state);
applyStatusBarColorSpaceAgnosticFlag(state);
if (mLp != null && mLp.copyFrom(mLpChanged) != 0) {
mWindowManager.updateViewLayout(mStatusBarView, mLp);
}
if (mHasTopUi != mHasTopUiChanged) {
try {
mActivityManager.setHasTopUi(mHasTopUiChanged);
} catch (RemoteException e) {
Log.e(TAG, "Failed to call setHasTopUi", e);
}
mHasTopUi = mHasTopUiChanged;
}
notifyStateChangedCallbacks();
}
设置了一些数据，接着调用mNotificationPanel.expand(true)展开滑动锁屏，这样我们就能看到锁屏界面了，到此为止滑动锁屏的加载已经分析完了，只分析了一个大概流程，里面有很多细节的东西需要实际应用到之后再去跟代码
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