一直想要整理一下keyguard（锁屏）模块的相关流程，由于各种原因总是没真正着手开始做，一直拖也不是个办法，所以就索性开始了。
这篇内容会比较偏分析，所以闲话就少扯点了。
锁屏模块位于framework中，有别于一般的上层应用，它的逻辑代码和view视图，资源文件散布在framework的几处地方，这也给新手分析该模块带来也一点的麻烦。下面我会试着来捋捋这些散落的珠子。
1.文件目录：
a，逻辑是Frameworks/base/policy/src/com/android/internal/policy/ impl/目录下
b，视图view是在 Framework/base/core/java/com/android/internal/ widget/路径下：
文件夹multiwaveview就是从4.0开始加入的环形解锁视图及相应动画实现。
c，资源文件在Framework/base/core/res/res/下。
这个就不贴目录了，和一般android应用一样，图片资源，布局文件都很规矩的放在相应分辨率的文件夹下。大致了解了锁屏模块文件分布后，我们一般就要开始看源代码了。
2，keyguard锁屏流程图:
现在看不明白的没关系可以先跳过，先看下面，再更几遍源码就会发现该图就是个小菜了。
3，keyguard锁屏view层次图：
一般4.0真机都会有五种锁屏方式：
这里和2.3有明显区别了，2.3的view视图如下：
可以看出来以前的锁屏流程是分正常锁屏和图案锁屏方式。在选择图案解锁方式，是不会显示正常解锁slidingview的。但是选择密码解锁就会出现需要用户二次解锁的情况。三星2.2就对此进行了流程优化统一。本人也试着做了，有兴趣可以。。。
4.0以后该流程得到了官方的统一，选择任何锁屏方式，用户都只需要一次解锁。流程上也更直观了。相信Google，必须是越来越good。
4，keyguard锁屏重要类分析：
1，KeyguardScreenback.java和KeyguardViewCallback.java
说明：接口两个，等着被LockPatternKeyguardView.java实例化。注意Keyguard ViewCallback.java还偷偷捞外快，同时替KeyguardViewMediator.java服务。
public interface KeyguardScreenCallback extends KeyguardViewCallback {
void goToLockScreen();//Transition to the lock screen.
void goToUnlockScreen();//Transition to the unlock screen.
void forgotPattern(boolean isForgotten);// The user forgot their pattern
boolean isSecure();//Whether the keyguard requires some sort of PIN.
/**
* @return Whether we are in a mode where we only want to verify the
* user can get past the keyguard.
*/
boolean isVerifyUnlockOnly();
/**
* Stay on me, but recreate me (so I can use a different layout).
*/
void recreateMe(Configuration config);
void takeEmergencyCallAction();//Take action to send an emergency call
void reportFailedUnlockAttempt();//user had a failed attempt to unlock
void reportSuccessfulUnlockAttempt();//successfully entered their password
/**
* Report whether we there's another way to unlock the device.
* @return true
*/
boolean doesFallbackUnlockScreenExist();
}
public interface KeyguardViewCallback {
/**
* Request the wakelock to be poked for the default amount of time.
*/
void pokeWakelock();//使屏幕保持亮一段时间。
void pokeWakelock(int millis);
void keyguardDone(boolean authenticated);// Report keyguard is done.
/**
* Report that the keyguard is done drawing.
*/
void keyguardDoneDrawing();//所有锁屏视图完成draw时调用该方法。
}
google的注释实在是太优雅了，都翻译成中文反而会有所误导且影响美观，单词看不明白的，有道去。实在懒的话，意会也行的；）
2． KeyguardScreen.java
说明：接口一个，坐等LockScreen.java等具体锁屏方式来实现它。
public interface KeyguardScreen {
boolean needsInput();//是否需要键盘进行输入
void onPause();//view不在最上层时被系统调用。
void onResume();//view重新掌权时被系统调用
void cleanUp();//view被扫地出门。
}
3． KeyguardStatusViewManager.java
说明：这个类是4.0后新增加的，其实它是从2.3的LockScreen.java分离了出来，所以它还是摆脱不了命运的束缚，依然要为LockScreen.java服务，而且它比以前更累了，如果条件需要它还要服侍其他如密码解锁，图形解锁等方式。功能就是状态视图总管。
/***
* Manages a number of views inside of LockScreen layouts. See below for a list of widgets
*/
class KeyguardStatusViewManager implements OnClickListener {
public KeyguardStatusViewManager(View view, KeyguardUpdateMonitor updateMonitor,LockPatternUtils lockPatternUtils, KeyguardScreenCallback callback,boolean showEmergencyButtonByDefault) {
if (DEBUG) Log.v(TAG, "KeyguardStatusViewManager()");
mContainer = view; //视图容器
mDateFormatString = getContext().getString(R.string.full_wday_month_day_no_year);//格式日期
mLockPatternUtils = lockPatternUtils;
mUpdateMonitor = updateMonitor;
mCallback = callback;
mCarrierView = (TextView) findViewById(R.id.carrier);//运营商标识
mDateView = (TextView) findViewById(R.id.date);//日期
mStatus1View = (TextView) findViewById(R.id.status1);//sim卡状态
mAlarmStatusView = (TextView) findViewById(R.id.alarm_status);//闹铃状态
mOwnerInfoView = (TextView) findViewById(R.id.propertyOf);
mTransportView = (TransportControlView) findViewById(R.id.transport);
mEmergencyCallButton = (Button) findViewById(R.id.emergencyCallButton);
mShowEmergencyButtonByDefault = showEmergencyButtonByDefault;
//紧急呼叫按钮
// Hide transport control view until we know we need to show it.
if (mTransportView != null) {
mTransportView.setVisibility(View.GONE);
}
if (mEmergencyCallButton != null) {
mEmergencyCallButton.setText(R.string.lockscreen_emergency_call);
mEmergencyCallButton.setOnClickListener(this);
mEmergencyCallButton.setFocusable(false); // touch only!
}
mTransientTextManager = new TransientTextManager(mCarrierView);
mUpdateMonitor.registerInfoCallback(mInfoCallback);
mUpdateMonitor.registerSimStateCallback(mSimStateCallback);
resetStatusInfo();//更新电池状态信息
refreshDate();//刷新时间
updateOwnerInfo();//更新所有者的信息
// Required to get Marquee to work.
final View scrollableViews[] = { mCarrierView, mDateView, mStatus1View, mOwnerInfoView,
mAlarmStatusView };
for (View v : scrollableViews) {
if (v != null) {
v.setSelected(true);
}
}
}
4． LockScreen.java
说明：五种锁屏方式之一，为系统默认设置选用，名为滑动解锁，也就是4.0的那个带锁的圆。它继承于LinearLayout并实现了KeyguardScreen接口，所以他具备了接受视图的解锁事件并作出响应。
/**
* The screen within {@link LockPatternKeyguardView} that shows general
* information about the device depending on its state, and how to get
* past it, as applicable.
*/
class LockScreen extends LinearLayout implements KeyguardScreen {
class SlidingTabMethods implements SlidingTab.OnTriggerListener, UnlockWidgetCommonMethods {
private final SlidingTab mSlidingTab;
SlidingTabMethods(SlidingTab slidingTab) {
mSlidingTab = slidingTab;
}
public void updateResources() {
.......
}
/** 解锁响应*/
public void onTrigger(View v, int whichHandle) {
if (whichHandle == SlidingTab.OnTriggerListener.LEFT_HANDLE) {
mCallback.goToUnlockScreen();
} else if (whichHandle == SlidingTab.OnTriggerListener.RIGHT_HANDLE) {
toggleRingMode();
mCallback.pokeWakelock();
}
}
/** {@inheritDoc} */
public void onGrabbedStateChange(View v, int grabbedState) {
.......
}
public View getView() {
return mSlidingTab;
}
public void reset(boolean animate) {
mSlidingTab.reset(animate);
}
public void ping() {
}
}
class WaveViewMethods implements WaveView.OnTriggerListener, UnlockWidgetCommonMethods {
private final WaveView mWaveView;
WaveViewMethods(WaveView waveView) {
mWaveView = waveView;
}
/** {@inheritDoc} */
public void onTrigger(View v, int whichHandle) {
if (whichHandle == WaveView.OnTriggerListener.CENTER_HANDLE) {
requestUnlockScreen();
}
}
/** {@inheritDoc} */
public void onGrabbedStateChange(View v, int grabbedState) {
// Don't poke the wake lock when returning to a state where the handle is
// not grabbed since that can happen when the system (instead of the user)
// cancels the grab.
if (grabbedState == WaveView.OnTriggerListener.CENTER_HANDLE) {
mCallback.pokeWakelock(STAY_ON_WHILE_GRABBED_TIMEOUT);
}
}
public void updateResources() {
}
public View getView() {
return mWaveView;
}
public void reset(boolean animate) {
mWaveView.reset();
}
public void ping() {
}
}
class MultiWaveViewMethods implements MultiWaveView.OnTriggerListener,
UnlockWidgetCommonMethods {
private final MultiWaveView mMultiWaveView;
private boolean mCameraDisabled;
MultiWaveViewMethods(MultiWaveView multiWaveView) {
mMultiWaveView = multiWaveView;
final boolean cameraDisabled = mLockPatternUtils.getDevicePolicyManager()
.getCameraDisabled(null);
if (cameraDisabled) {
Log.v(TAG, "Camera disabled by Device Policy");
mCameraDisabled = true;
} else {
// Camera is enabled if resource is initially defined for MultiWaveView
// in the lockscreen layout file
mCameraDisabled = mMultiWaveView.getTargetResourceId()
!= R.array.lockscreen_targets_with_camera;
}
}
这个类的主要作用就是提供了三种不同时期的滑动解锁方案重载，具体用哪种已经在keyguard_screen_tab_unlock.xml中配置好了。
5． KeyguardViewBase.java
说明：一个抽象类，里面封装了一些抽象方法,并完成对各种按键的监听。条件允许的话他还会拦截keyEvent，从中作梗。
public abstract class KeyguardViewBase extends FrameLayout {
public boolean dispatchKeyEvent(KeyEvent event) {
if (shouldEventKeepScreenOnWhileKeyguardShowing(event)) {
mCallback.pokeWakelock();
}
if (interceptMediaKey(event)) {
return true;
}
return super.dispatchKeyEvent(event);
}
private boolean shouldEventKeepScreenOnWhileKeyguardShowing(KeyEvent event) {
if (event.getAction() != KeyEvent.ACTION_DOWN) {
return false;
}
switch (event.getKeyCode()) {
case KeyEvent.KEYCODE_DPAD_DOWN:
case KeyEvent.KEYCODE_DPAD_LEFT:
case KeyEvent.KEYCODE_DPAD_RIGHT:
case KeyEvent.KEYCODE_DPAD_UP:
return false;
default:
return true;
}
}
private boolean interceptMediaKey(KeyEvent event) {
final int keyCode = event.getKeyCode();
if (event.getAction() == KeyEvent.ACTION_DOWN) {
switch (keyCode) {
case KeyEvent.KEYCODE_MEDIA_PLAY:
case KeyEvent.KEYCODE_MEDIA_PAUSE:
case KeyEvent.KEYCODE_MEDIA_PLAY_PAUSE:
......
}
6．LockPatternKeyguardView.java
说明：1-6的最终boss，上面的零碎都直接或间接为它工作，他的作用呢，可以参考上面的锁屏view层次图。一句话它是锁屏的最高权威，该整那样，它说了算，鉴于它太过NB，这里就不贴代码了，读者必须亲自膜拜三遍。
7． KeyguardViewManager.java
说明：封装了WindowManager，可以随性改变锁屏视图的创建，显示，隐藏及重新设定。
/**
* Manages creating, showing, hiding and resetting the keyguard. Calls back
* via {@link com.android.internal.policy.impl.KeyguardViewCallback} to poke
* the wake lock and report that the keyguard is done, which is in turn,
* reported to this class by the current {@link KeyguardViewBase}.
*/
public class KeyguardViewManager implements KeyguardWindowController {
private final KeyguardViewProperties mKeyguardViewProperties;
private final KeyguardUpdateMonitor mUpdateMonitor;
private WindowManager.LayoutParams mWindowLayoutParams;
private boolean mNeedsInput = false;
private FrameLayout mKeyguardHost;
private KeyguardViewBase mKeyguardView;
.....
protected void dispatchDraw(Canvas canvas) {
super.dispatchDraw(canvas);
mCallback.keyguardDoneDrawing();
}
}
/**
* Show the keyguard. Will handle creating and attaching to the view manager
* lazily.
*/
public synchronized void show() {
.....
if (mScreenOn) {
mKeyguardView.show();
}
}
// Disable aspects of the system/status/navigation bars that are not appropriate or
// useful for the lockscreen but can be re-shown by dialogs or SHOW_WHEN_LOCKED activities.
// Other disabled bits are handled by the KeyguardViewMediator talking directly to the
// status bar service.
int visFlags =
( View.STATUS_BAR_DISABLE_BACK
| View.STATUS_BAR_DISABLE_HOME
);
mKeyguardHost.setSystemUiVisibility(visFlags);
mViewManager.updateViewLayout(mKeyguardHost, mWindowLayoutParams);
mKeyguardHost.setVisibility(View.VISIBLE);
mKeyguardView.requestFocus();
}
public void setNeedsInput(boolean needsInput) {
...
}
/**
* Reset the state of the view.
*/
public synchronized void reset() {
}
public synchronized void onScreenTurnedOff() {
}
public synchronized void onScreenTurnedOn(
final KeyguardViewManager.ShowListener showListener) {
// Caller should wait for this window to be shown before turning
// on the screen.
}
public synchronized void verifyUnlock() {
if (DEBUG) Log.d(TAG, "verifyUnlock()");
show();
mKeyguardView.verifyUnlock();
}
/**
* A key has woken the device.
*/
public boolean wakeWhenReadyTq(int keyCode) {
.....
}
/**
* Hides the keyguard view
*/
public synchronized void hide() {
.....
}
/**
* @return Whether the keyguard is showing
*/
public synchronized boolean isShowing() {
return (mKeyguardHost != null && mKeyguardHost.getVisibility() == View.VISIBLE);
}
8． KeyguardUpdateMonitor.java
说明：监听系统状态值的改变如时间、SIM卡状态、电池电量等，状态值的改变会回调监听了该状态信息的对象实例。如果只是关注功能的话只需要看hadle里面的每个消息调用的方法即可。
/**
* Watches for updates that may be interesting to the keyguard, and provides
* the up to date information as well as a registration for callbacks that care
* to be updated.
*
* Note: under time crunch, this has been extended to include some stuff that
* doesn't really belong here. see {@link #handleBatteryUpdate} where it shutdowns
* the device, and {@link #getFailedAttempts()}, {@link #reportFailedAttempt()}
* and {@link #clearFailedAttempts()}. Maybe we should rename this 'KeyguardContext'...
*/
public class KeyguardUpdateMonitor {
private Handler mHandler;
private ContentObserver mContentObserver;
private int mRingMode;
private int mPhoneState;
......
/**
* SIM卡状态改变捕获赋值。
* the intent and provide a {@link SimCard.State} result.
*/
private static class SimArgs {
public final IccCard.State simState;
private SimArgs(Intent intent) {
if (!TelephonyIntents.ACTION_SIM_STATE_CHANGED.equals(intent.getAction())) {
throw new IllegalArgumentException("only handles intent ACTION_SIM_STATE_CHANGED");
}
String stateExtra = intent.getStringExtra(IccCard.INTENT_KEY_ICC_STATE);
if (IccCard.INTENT_VALUE_ICC_ABSENT.equals(stateExtra)) {
final String absentReason = intent
.getStringExtra(IccCard.INTENT_KEY_LOCKED_REASON);
if (IccCard.INTENT_VALUE_ABSENT_ON_PERM_DISABLED.equals(
absentReason)) {
this.simState = IccCard.State.PERM_DISABLED;
} else {
this.simState = IccCard.State.ABSENT;
}
} else if (IccCard.INTENT_VALUE_ICC_READY.equals(stateExtra)) {
this.simState = IccCard.State.READY;
} else if (IccCard.INTENT_VALUE_ICC_LOCKED.equals(stateExtra)) {
final String lockedReason = intent
.getStringExtra(IccCard.INTENT_KEY_LOCKED_REASON);
if (IccCard.INTENT_VALUE_LOCKED_ON_PIN.equals(lockedReason)) {
this.simState = IccCard.State.PIN_REQUIRED;
} else if (IccCard.INTENT_VALUE_LOCKED_ON_PUK.equals(lockedReason)) {
this.simState = IccCard.State.PUK_REQUIRED;
} else {
this.simState = IccCard.State.UNKNOWN;
}
} else if (IccCard.INTENT_VALUE_LOCKED_NETWORK.equals(stateExtra)) {
this.simState = IccCard.State.NETWORK_LOCKED;
} else {
this.simState = IccCard.State.UNKNOWN;
}
}
public String toString() {
return simState.toString();
}
}
public KeyguardUpdateMonitor(Context context) {
mContext = context;
mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case MSG_TIME_UPDATE:
handleTimeUpdate();
break;
case MSG_BATTERY_UPDATE:
handleBatteryUpdate(msg.arg1, msg.arg2);
break;
case MSG_CARRIER_INFO_UPDATE:
handleCarrierInfoUpdate();
break;
case MSG_SIM_STATE_CHANGE:
handleSimStateChange((SimArgs) msg.obj);
break;
case MSG_RINGER_MODE_CHANGED:
handleRingerModeChange(msg.arg1);
break;
case MSG_PHONE_STATE_CHANGED:
handlePhoneStateChanged((String)msg.obj);
break;
case MSG_CLOCK_VISIBILITY_CHANGED:
handleClockVisibilityChanged();
break;
case MSG_DEVICE_PROVISIONED:
handleDeviceProvisioned();
break;
}
}
};
9．KeyguardViewMediator.java
说明：也是boss级别的，虽然明面上不及LockPatternKeyguardView.java，但论实权，是个深藏不露的实力派。奈何可能有把柄在他人之手，所以他必须低调，任劳任怨，为PhoneWindowManager.java所各种差遣。看它的话先把开头的50来行英文注释整清楚，然后在跳到handle里面看一下每个消息对应的执行函数，这样对这个所谓调度者就有个大概的理解了。然后就可以具体功能流程具体分析了。
/**
*有关键盘锁请求的调度者。包括键盘锁状态的查询，power management事件影响键盘锁是否应该被显示或者重置，特定的回调函数来
*通知window manager键盘锁是什么时候显示，以及接受view视图传过来的消息表明已经成功完成解锁。
*请注意键盘锁是在灭屏后立即被调用显示的。这样当你点亮屏幕，锁屏才能第一时间显示出来。
*例如外部事件调度锁屏视图流程：
*
*-灭屏动作-》重置锁屏并显示它为下次点亮屏幕做好准备。
*-锁屏很自然流畅的打开了-》如果他不是安全的，隐藏之。
*
*来自于锁屏视图的事件：
*-用户成功完成解锁条件-》隐藏锁屏视图，不再对输入事件进行拦截。
*请再注意：第三方应用通过条用power managment实例可以屏蔽系统的键盘锁。
*
*线程和同步：
*该类是由WindowManagerPolicy创建并运行在它的线程里，锁屏UI也是这个类的构造函数里面产生。这个apis也可以被其他线程所调用。
*然而，这个类的方法手势同步的，同时任何一个锁屏视图都会发消息到handle来保证它是在锁屏UI线程里面执行的。
*/
public class KeyguardViewMediator implements KeyguardViewCallback,
KeyguardUpdateMonitor.InfoCallback, KeyguardUpdateMonitor.SimStateCallback {
private static final int KEYGUARD_DISPLAY_TIMEOUT_DELAY_DEFAULT = 30000;
/**
* This handler will be associated with the policy thread, which will also
* be the UI thread of the keyguard. Since the apis of the policy, and therefore
* this class, can be called by other threads, any action that directly
* interacts with the keyguard ui should be posted to this handler, rather
* than called directly.
*/
private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
switch (msg.what) {
case TIMEOUT:
handleTimeout(msg.arg1);
return ;
case SHOW:
handleShow();
return ;
case HIDE:
handleHide();
return ;
case RESET:
handleReset();
return ;
case VERIFY_UNLOCK:
handleVerifyUnlock();
return;
case NOTIFY_SCREEN_OFF:
handleNotifyScreenOff();
return;
case NOTIFY_SCREEN_ON:
handleNotifyScreenOn((KeyguardViewManager.ShowListener)msg.obj);
return;
case WAKE_WHEN_READY:
handleWakeWhenReady(msg.arg1);
return;
case KEYGUARD_DONE:
handleKeyguardDone(msg.arg1 != 0);
return;
case KEYGUARD_DONE_DRAWING:
handleKeyguardDoneDrawing();
return;
case KEYGUARD_DONE_AUTHENTICATING:
keyguardDone(true);
return;
case SET_HIDDEN:
handleSetHidden(msg.arg1 != 0);
break;
case KEYGUARD_TIMEOUT:
synchronized (KeyguardViewMediator.this) {
doKeyguardLocked();
}
break;
}
}
};
private void adjustStatusBarLocked() {
......//控制是否能在锁屏界面下拉状态栏。
}
}
10． PhoneWindowManager.java
说明：在Android中的地位犹如封疆之王爷，此等人物，岂能一眼看透并妄加揣测。需时日翻阅各种资料假以研究才能得出个大概.......此乃后话，当另谋篇幅。
5，2.3keyguard锁屏解的几个小问题，贴上仅供娱乐：
后续待补充。
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