前几天遇到一个低概率复现锁屏界面不显示，只显示状态栏的问题，跟了下锁屏界面启动显示的流程，在这分享下，也方便以后自己查看。前面简单介绍了下Zygote启动流程， Zygote进程启动后会首先创建一个SystemServer进程，SystemServer进程在调用startOtherServices同时也会调用WindowManagerService的systemReady()方法
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//frameworks/base/services/java/com/android/server/SystemServer.java
-
private void startOtherServices() {
-
...
-
wm = WindowManagerService.main(context, inputManager,
-
mFactoryTestMode != FactoryTest.FACTORY_TEST_LOW_LEVEL,
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!mFirstBoot, mOnlyCore);
-
...
-
try {
-
wm.systemReady();
-
Slog.i("jason11", "SystemServer wm.systemReady");
-
} catch (Throwable e) {
-
reportWtf("making Window Manager Service ready", e);
-
}
-
...
-
}
在WindowManagerService中直接调用了PhoneWindowManager里的systemReady()
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//frameworks/base/services/core/java/com/android/server/wm/WindowManagerService.java
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//final WindowManagerPolicy mPolicy = new PhoneWindowManager();
-
public void systemReady() {
-
mPolicy.systemReady();
-
}
在PhoneWindowManager的systemReady()会根据一个Boolean值bindKeyguardNow来决定是否绑定keyguard
service
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//frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java
-
/** {@inheritDoc} */
-
@Override
-
public void systemReady() {
-
mKeyguardDelegate = new KeyguardServiceDelegate(mContext);
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mKeyguardDelegate.onSystemReady();
-
-
readCameraLensCoverState();
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updateUiMode();
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boolean bindKeyguardNow;
-
synchronized (mLock) {
-
updateOrientationListenerLp();
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mSystemReady = true;
-
mHandler.post(new Runnable() {
-
@Override
-
public void run() {
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updateSettings();
-
}
-
});
-
-
bindKeyguardNow = mDeferBindKeyguard;
-
if (bindKeyguardNow) {
-
// systemBooted ran but wasn't able to bind to the Keyguard, we'll do it now.
-
mDeferBindKeyguard = false;
-
}
-
}
-
if (bindKeyguardNow) {
-
mKeyguardDelegate.bindService(mContext);
-
mKeyguardDelegate.onBootCompleted();
-
}
-
mSystemGestures.systemReady();
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}
看到这里，可能会想到如果bindKeyguardNow为false就会不绑定，后面通过继续跟踪发现在PhoneWindowManager的systemBooted()里也会去绑定keyguard
service，如果在systemBooted里绑定了就不在systemReady里再去绑定，自己测试的时候是在systemBooted绑定的
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//frameworks/base/services/core/java/com/android/server/policy/PhoneWindowManager.java
-
/** {@inheritDoc} */
-
@Override
-
public void systemBooted() {
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boolean bindKeyguardNow = false;
-
synchronized (mLock) {
-
// Time to bind Keyguard; take care to only bind it once, either here if ready or
-
// in systemReady if not.
-
if (mKeyguardDelegate != null) {
-
bindKeyguardNow = true;
-
} else {
-
// Because mKeyguardDelegate is null, we know that the synchronized block in
-
// systemReady didn't run yet and setting this will actually have an effect.
-
mDeferBindKeyguard = true;
-
}
-
}
-
if (bindKeyguardNow) {
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mKeyguardDelegate.bindService(mContext);
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mKeyguardDelegate.onBootCompleted();
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}
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synchronized (mLock) {
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mSystemBooted = true;
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}
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startedWakingUp();
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screenTurningOn(null);
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screenTurnedOn();
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}
下面就通过如下的时序图看看是如何调用到systemBooted的，就不在一步步跟了
通过上面的分析知道，无论是在systemReady或systemBooted，都调用了KeyguardServiceDelegate对象的bindService方法，下面就以这个方法开始，看看锁屏界面是怎么显示出来的，先看看下面的时序图，再来分步讲解
1、先来看看在KeyguardServiceDelegate如何绑定KeyguardService的
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//frameworks/base/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java
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public class KeyguardServiceDelegate {
-
...
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public void bindService(Context context) {
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Intent intent = new Intent();
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final Resources resources = context.getApplicationContext().getResources();
-
-
final ComponentName keyguardComponent = ComponentName.unflattenFromString(
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resources.getString(com.android.internal.R.string.config_keyguardComponent));
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intent.setComponent(keyguardComponent);
-
-
if (!context.bindServiceAsUser(intent, mKeyguardConnection,
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Context.BIND_AUTO_CREATE, UserHandle.OWNER)) {
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Log.v(TAG, "*** Keyguard: can't bind to " + keyguardComponent);
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mKeyguardState.showing = false;
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mKeyguardState.showingAndNotOccluded = false;
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mKeyguardState.secure = false;
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synchronized (mKeyguardState) {
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// TODO: Fix synchronisation model in this class. The other state in this class
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// is at least self-healing but a race condition here can lead to the scrim being
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// stuck on keyguard-less devices.
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mKeyguardState.deviceHasKeyguard = false;
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hideScrim();
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}
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} else {
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if (DEBUG) Log.v(TAG, "*** Keyguard started");
-
}
-
}
-
...
-
}
在bindService中调用了bindServiceAsUser绑定指定intent的service，config_keyguardComponent的定义如下
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//frameworks/base/core/res/res/values/config.xml
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<!-- Keyguard component -->
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<string name="config_keyguardComponent" translatable="false">com.android.systemui/com.android.systemui.keyguard.KeyguardService</string>
当绑定成功后会调用mKeyguardConnection里的onServiceConnected方法
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//frameworks/base/services/core/java/com/android/server/policy/keyguard/KeyguardServiceDelegate.java
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public class KeyguardServiceDelegate {
-
...
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private final ServiceConnection mKeyguardConnection = new ServiceConnection() {
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@Override
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public void onServiceConnected(ComponentName name, IBinder service) {
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if (DEBUG) Log.v(TAG, "*** Keyguard connected (yay!)");
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mKeyguardService = new KeyguardServiceWrapper(mContext,
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IKeyguardService.Stub.asInterface(service));
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if (mKeyguardState.systemIsReady) {
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// If the system is ready, it means keyguard crashed and restarted.
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mKeyguardService.onSystemReady();
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// This is used to hide the scrim once keyguard displays.
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if (mKeyguardState.interactiveState == INTERACTIVE_STATE_AWAKE) {
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mKeyguardService.onStartedWakingUp();
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}
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if (mKeyguardState.screenState == SCREEN_STATE_ON
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|| mKeyguardState.screenState == SCREEN_STATE_TURNING_ON) {
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mKeyguardService.onScreenTurningOn(
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new KeyguardShowDelegate(mDrawnListenerWhenConnect));
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}
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if (mKeyguardState.screenState == SCREEN_STATE_ON) {
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mKeyguardService.onScreenTurnedOn();
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}
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mDrawnListenerWhenConnect = null;
-
}
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if (mKeyguardState.bootCompleted) {
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mKeyguardService.onBootCompleted();
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}
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if (mKeyguardState.occluded) {
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mKeyguardService.setOccluded(mKeyguardState.occluded);
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}
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}
-
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@Override
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public void onServiceDisconnected(ComponentName name) {
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if (DEBUG) Log.v(TAG, "*** Keyguard disconnected (boo!)");
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mKeyguardService = null;
-
}
-
-
};
-
...
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}
当mKeyguardState.systemIsReady为true是，就会通过KeyguardServiceWrapper的实例mKeyguardService调用onSystemReady方法，在KeyguardServiceWrapper的onSystemReady里调用了上面刚刚绑定成功的KeyguardService的onSystemReady方法
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//frameworks/base/services/core/java/com/android/server/policy/keyguard/KeyguardServiceWrapper.java
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public class KeyguardServiceWrapper implements IKeyguardService {
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...
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@Override // Binder interface
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public void onSystemReady() {
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try {
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mService.onSystemReady();
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} catch (RemoteException e) {
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Slog.w(TAG , "Remote Exception", e);
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}
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}
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...
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}
在KeyguardService的onSystemReady里调用了KeyguardViewMediator里的onSystemReady，在这里就不贴这个代码了，直接看看KeyguardViewMediator.onSystemReady这个里面干啥了
2、KeyguardViewMediator.onSystemReady
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//frameworks/base/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardViewMediator.java
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public class KeyguardViewMediator extends SystemUI {
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...
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public void onSystemReady() {
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mSearchManager = (SearchManager) mContext.getSystemService(Context.SEARCH_SERVICE);
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synchronized (this) {
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if (DEBUG) Log.d(TAG, "onSystemReady");
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mSystemReady = true;
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doKeyguardLocked(null);
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mUpdateMonitor.registerCallback(mUpdateCallback);
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}
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// Most services aren't available until the system reaches the ready state, so we
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// send it here when the device first boots.
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maybeSendUserPresentBroadcast();
-
}
-
...
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}
在这个方法里主要调用了doKeyguardLocked和注册了KeyguardUpdateMonitorCallback
3、通过调用doKeyguardLocked显示锁屏界面
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//frameworks/base/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardViewMediator.java
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public class KeyguardViewMediator extends SystemUI {
-
...
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private void doKeyguardLocked(Bundle options) {
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// if another app is disabling us, don't show
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if (!mExternallyEnabled) {
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if (DEBUG) Log.d(TAG, "doKeyguard: not showing because externally disabled");
-
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// note: we *should* set mNeedToReshowWhenReenabled=true here, but that makes
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// for an occasional ugly flicker in this situation:
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// 1) receive a call with the screen on (no keyguard) or make a call
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// 2) screen times out
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// 3) user hits key to turn screen back on
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// instead, we reenable the keyguard when we know the screen is off and the call
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// ends (see the broadcast receiver below)
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// TODO: clean this up when we have better support at the window manager level
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// for apps that wish to be on top of the keyguard
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return;
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}
-
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// if the keyguard is already showing, don't bother
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if (mStatusBarKeyguardViewManager.isShowing()) {
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if (DEBUG) Log.d(TAG, "doKeyguard: not showing because it is already showing");
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resetStateLocked();
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return;
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}
-
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// if the setup wizard hasn't run yet, don't show
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final boolean requireSim = !SystemProperties.getBoolean("keyguard.no_require_sim", false);
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final boolean absent = SubscriptionManager.isValidSubscriptionId(
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mUpdateMonitor.getNextSubIdForState(IccCardConstants.State.ABSENT));
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final boolean disabled = SubscriptionManager.isValidSubscriptionId(
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mUpdateMonitor.getNextSubIdForState(IccCardConstants.State.PERM_DISABLED));
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final boolean lockedOrMissing = mUpdateMonitor.isSimPinSecure()
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|| ((absent || disabled) && requireSim);
-
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if (!lockedOrMissing && shouldWaitForProvisioning()) {
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if (DEBUG) Log.d(TAG, "doKeyguard: not showing because device isn't provisioned"
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+ " and the sim is not locked or missing");
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return;
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}
-
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if (mLockPatternUtils.isLockScreenDisabled(KeyguardUpdateMonitor.getCurrentUser())
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&& !lockedOrMissing) {
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if (DEBUG) Log.d(TAG, "doKeyguard: not showing because lockscreen is off");
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return;
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}
-
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if (mLockPatternUtils.checkVoldPassword(KeyguardUpdateMonitor.getCurrentUser())) {
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if (DEBUG) Log.d(TAG, "Not showing lock screen since just decrypted");
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// Without this, settings is not enabled until the lock screen first appears
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setShowingLocked(false);
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hideLocked();
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mUpdateMonitor.reportSuccessfulStrongAuthUnlockAttempt();
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return;
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}
-
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if (DEBUG) Log.d(TAG, "doKeyguard: showing the lock screen");
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showLocked(options);
-
}
-
...
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}
这段代码主要是在是否要显示锁屏之前做了5个判断：1.如果启用第三方锁屏界面，不显示原生界面；2.锁屏界面已经显示了话，重新更新下状态；3.如果第一次开机引导界面setup wizard 还没有运行，也先不显示；4.屏幕没有亮不显示；5.当前正在解密界面不显示。如果这几个条件都不满足，则调用showLocked显示锁屏界面。在showLocked通过mHandler发送Message，在handleMessage里“case
SHOW:”时调用handleShow
4、在handleShow里设置一些锁屏状态和显示锁屏界面
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//frameworks/base/packages/SystemUI/src/com/android/systemui/keyguard/KeyguardViewMediator.java
-
public class KeyguardViewMediator extends SystemUI {
-
...
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private void handleShow(Bundle options) {
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synchronized (KeyguardViewMediator.this) {
-
if (!mSystemReady) {
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if (DEBUG) Log.d(TAG, "ignoring handleShow because system is not ready.");
-
return;
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} else {
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if (DEBUG) Log.d(TAG, "handleShow");
-
}
-
-
setShowingLocked(true);
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mStatusBarKeyguardViewManager.show(options);
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mHiding = false;
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mWakeAndUnlocking = false;
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resetKeyguardDonePendingLocked();
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mHideAnimationRun = false;
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updateActivityLockScreenState();
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adjustStatusBarLocked();
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userActivity();
-
-
mShowKeyguardWakeLock.release();
-
}
-
mKeyguardDisplayManager.show();
-
}
-
...
-
}
5、通过调用StatusBarKeyguardViewManager的show重置当前状态显示keyguard
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//frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/StatusBarKeyguardViewManager.java
-
public class StatusBarKeyguardViewManager {
-
...
-
public void show(Bundle options) {
-
mShowing = true;
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mStatusBarWindowManager.setKeyguardShowing(true);
-
mScrimController.abortKeyguardFadingOut();
-
reset();
-
}
-
...
-
}
在reset里调用本类的showBouncerOrKeyguard，在这个方法里通过KeyguardBouncer的实例mBouncer调用prepare()，在prepare里调用了KeyguardHostView的showPrimarySecurityScreen
6、KeyguardSecurityContainer.showPrimarySecurityScreen
在KeyguardHostView的showPrimarySecurityScreen里调用KeyguardSecurityContainer的showPrimarySecurityScreen方法，如下
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//frameworks/base/packages/Keyguard/src/com/android/keyguard/KeyguardSecurityContainer.java
-
public class KeyguardSecurityContainer extends FrameLayout implements KeyguardSecurityView {
-
...
-
void showPrimarySecurityScreen(boolean turningOff) {
-
SecurityMode securityMode = mSecurityModel.getSecurityMode();
-
if (DEBUG) Log.v(TAG, "showPrimarySecurityScreen(turningOff=" + turningOff + ")");
-
showSecurityScreen(securityMode);
-
}
-
...
-
}
在这个方法里调用了showSecurityScreen，根据mSecurityModel.getSecurityMode()获取的SecurityMode来显示不同界面，SecurityMode定义如下
-
//frameworks/base/packages/Keyguard/src/com/android/keyguard/KeyguardSecurityModel.java
-
public class KeyguardSecurityModel {
-
public enum SecurityMode {
-
Invalid, // NULL state
-
None, // No security enabled
-
Pattern, // Unlock by drawing a pattern.
-
Password, // Unlock by entering an alphanumeric password
-
PIN, // Strictly numeric password
-
SimPin, // Unlock by entering a sim pin.
-
SimPuk // Unlock by entering a sim puk
-
}
-
...
-
}
showSecurityScreen方法如下：
-
//frameworks/base/packages/Keyguard/src/com/android/keyguard/KeyguardSecurityContainer.java
-
public class KeyguardSecurityContainer extends FrameLayout implements KeyguardSecurityView {
-
...
-
private void showSecurityScreen(SecurityMode securityMode) {
-
if (DEBUG) Log.d(TAG, "showSecurityScreen(" + securityMode + ")");
-
-
if (securityMode == mCurrentSecuritySelection) return;
-
-
KeyguardSecurityView oldView = getSecurityView(mCurrentSecuritySelection);
-
KeyguardSecurityView newView = getSecurityView(securityMode);//根据securityMode获取对应的view
-
-
// Emulate Activity life cycle
-
if (oldView != null) {
-
oldView.onPause();
-
oldView.setKeyguardCallback(mNullCallback); // ignore requests from old view
-
}
-
if (securityMode != SecurityMode.None) {
-
newView.onResume(KeyguardSecurityView.VIEW_REVEALED);
-
newView.setKeyguardCallback(mCallback);
-
}
-
-
// Find and show this child.
-
final int childCount = mSecurityViewFlipper.getChildCount();
-
-
final int securityViewIdForMode = getSecurityViewIdForMode(securityMode);
-
for (int i = 0; i < childCount; i++) {
-
if (mSecurityViewFlipper.getChildAt(i).getId() == securityViewIdForMode) {
-
mSecurityViewFlipper.setDisplayedChild(i);
-
break;
-
}
-
}
-
-
mCurrentSecuritySelection = securityMode;
-
mSecurityCallback.onSecurityModeChanged(securityMode,
-
securityMode != SecurityMode.None && newView.needsInput());
-
}
-
...
-
}
到这里锁屏就启动完成了，这里简单总结一下：
1. 在KeyguardServiceDelegate里绑定KeyguardService，并调用onSystemReady方法。
2. KeyguardViewMediator里调用doKeyguardLocked来决定是否需要显示锁屏界面；如果显示则调用StatusBarKeyguardViewManager的show，最后调用到KeyguardHostView的showPrimarySecurityScreen()。
3. 在KeyguardSecurityContainer的showPrimarySecurityScreen利用mSecurityModel.getSecurityMode()获取当前的securityMode，传入showSecurityScreen来显示不同锁屏界面。
原文地址： http://blog.csdn.net/yin1031468524/article/details/56284449