一直想要整理一下keyguard（鎖屏）模塊的相關流程，由於各種原因總是沒真正着手開始做，一直拖也不是個辦法，所以就索性開始了。
這篇內容會比較偏分析，所以閑話就少扯點了。
鎖屏模塊位於framework中，有別於一般的上層應用，它的邏輯代碼和view視圖，資源文件散布在framework的幾處地方，這也給新手分析該模塊帶來也一點的麻煩。下面我會試着來捋捋這些散落的珠子。
1.文件目錄：
a，邏輯是Frameworks/base/policy/src/com/android/internal/policy/ impl/目錄下
b，視圖view是在 Framework/base/core/java/com/android/internal/ widget/路徑下：
文件夾multiwaveview就是從4.0開始加入的環形解鎖視圖及相應動畫實現。
c，資源文件在Framework/base/core/res/res/下。
這個就不貼目錄了，和一般android應用一樣，圖片資源，布局文件都很規矩的放在相應分辨率的文件夾下。大致了解了鎖屏模塊文件分布后，我們一般就要開始看源代碼了。
2，keyguard鎖屏流程圖:
現在看不明白的沒關系可以先跳過，先看下面，再更幾遍源碼就會發現該圖就是個小菜了。
3，keyguard鎖屏view層次圖：
一般4.0真機都會有五種鎖屏方式：
這里和2.3有明顯區別了，2.3的view視圖如下：
可以看出來以前的鎖屏流程是分正常鎖屏和圖案鎖屏方式。在選擇圖案解鎖方式，是不會顯示正常解鎖slidingview的。但是選擇密碼解鎖就會出現需要用戶二次解鎖的情況。三星2.2就對此進行了流程優化統一。本人也試着做了，有興趣可以。。。
4.0以后該流程得到了官方的統一，選擇任何鎖屏方式，用戶都只需要一次解鎖。流程上也更直觀了。相信Google，必須是越來越good。
4，keyguard鎖屏重要類分析：
1，KeyguardScreenback.java和KeyguardViewCallback.java
說明：接口兩個，等着被LockPatternKeyguardView.java實例化。注意Keyguard ViewCallback.java還偷偷撈外快，同時替KeyguardViewMediator.java服務。
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();//使屏幕保持亮一段時間。
void pokeWakelock(int millis);
void keyguardDone(boolean authenticated);// Report keyguard is done.
/**
* Report that the keyguard is done drawing.
*/
void keyguardDoneDrawing();//所有鎖屏視圖完成draw時調用該方法。
}
google的注釋實在是太優雅了，都翻譯成中文反而會有所誤導且影響美觀，單詞看不明白的，有道去。實在懶的話，意會也行的；）
2． KeyguardScreen.java
說明：接口一個，坐等LockScreen.java等具體鎖屏方式來實現它。
public interface KeyguardScreen {
boolean needsInput();//是否需要鍵盤進行輸入
void onPause();//view不在最上層時被系統調用。
void onResume();//view重新掌權時被系統調用
void cleanUp();//view被掃地出門。
}
3． KeyguardStatusViewManager.java
說明：這個類是4.0后新增加的，其實它是從2.3的LockScreen.java分離了出來，所以它還是擺脫不了命運的束縛，依然要為LockScreen.java服務，而且它比以前更累了，如果條件需要它還要服侍其他如密碼解鎖，圖形解鎖等方式。功能就是狀態視圖總管。
/***
* 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; //視圖容器
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);//運營商標識
mDateView = (TextView) findViewById(R.id.date);//日期
mStatus1View = (TextView) findViewById(R.id.status1);//sim卡狀態
mAlarmStatusView = (TextView) findViewById(R.id.alarm_status);//鬧鈴狀態
mOwnerInfoView = (TextView) findViewById(R.id.propertyOf);
mTransportView = (TransportControlView) findViewById(R.id.transport);
mEmergencyCallButton = (Button) findViewById(R.id.emergencyCallButton);
mShowEmergencyButtonByDefault = showEmergencyButtonByDefault;
//緊急呼叫按鈕
// 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();//更新電池狀態信息
refreshDate();//刷新時間
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
說明：五種鎖屏方式之一，為系統默認設置選用，名為滑動解鎖，也就是4.0的那個帶鎖的圓。它繼承於LinearLayout並實現了KeyguardScreen接口，所以他具備了接受視圖的解鎖事件並作出響應。
/**
* 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() {
.......
}
/** 解鎖響應*/
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;
}
}
這個類的主要作用就是提供了三種不同時期的滑動解鎖方案重載，具體用哪種已經在keyguard_screen_tab_unlock.xml中配置好了。
5． KeyguardViewBase.java
說明：一個抽象類，里面封裝了一些抽象方法,並完成對各種按鍵的監聽。條件允許的話他還會攔截keyEvent，從中作梗。
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
說明：1-6的最終boss，上面的零碎都直接或間接為它工作，他的作用呢，可以參考上面的鎖屏view層次圖。一句話它是鎖屏的最高權威，該整那樣，它說了算，鑒於它太過NB，這里就不貼代碼了，讀者必須親自膜拜三遍。
7． KeyguardViewManager.java
說明：封裝了WindowManager，可以隨性改變鎖屏視圖的創建，顯示，隱藏及重新設定。
/**
* 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
說明：監聽系統狀態值的改變如時間、SIM卡狀態、電池電量等，狀態值的改變會回調監聽了該狀態信息的對象實例。如果只是關注功能的話只需要看hadle里面的每個消息調用的方法即可。
/**
* 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卡狀態改變捕獲賦值。
* 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
說明：也是boss級別的，雖然明面上不及LockPatternKeyguardView.java，但論實權，是個深藏不露的實力派。奈何可能有把柄在他人之手，所以他必須低調，任勞任怨，為PhoneWindowManager.java所各種差遣。看它的話先把開頭的50來行英文注釋整清楚，然后在跳到handle里面看一下每個消息對應的執行函數，這樣對這個所謂調度者就有個大概的理解了。然后就可以具體功能流程具體分析了。
/**
*有關鍵盤鎖請求的調度者。包括鍵盤鎖狀態的查詢，power management事件影響鍵盤鎖是否應該被顯示或者重置，特定的回調函數來
*通知window manager鍵盤鎖是什么時候顯示，以及接受view視圖傳過來的消息表明已經成功完成解鎖。
*請注意鍵盤鎖是在滅屏后立即被調用顯示的。這樣當你點亮屏幕，鎖屏才能第一時間顯示出來。
*例如外部事件調度鎖屏視圖流程：
*
*-滅屏動作-》重置鎖屏並顯示它為下次點亮屏幕做好准備。
*-鎖屏很自然流暢的打開了-》如果他不是安全的，隱藏之。
*
*來自於鎖屏視圖的事件：
*-用戶成功完成解鎖條件-》隱藏鎖屏視圖，不再對輸入事件進行攔截。
*請再注意：第三方應用通過條用power managment實例可以屏蔽系統的鍵盤鎖。
*
*線程和同步：
*該類是由WindowManagerPolicy創建並運行在它的線程里，鎖屏UI也是這個類的構造函數里面產生。這個apis也可以被其他線程所調用。
*然而，這個類的方法手勢同步的，同時任何一個鎖屏視圖都會發消息到handle來保證它是在鎖屏UI線程里面執行的。
*/
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() {
......//控制是否能在鎖屏界面下拉狀態欄。
}
}
10． PhoneWindowManager.java
說明：在Android中的地位猶如封疆之王爺，此等人物，豈能一眼看透並妄加揣測。需時日翻閱各種資料假以研究才能得出個大概.......此乃后話，當另謀篇幅。
5，2.3keyguard鎖屏解的幾個小問題，貼上僅供娛樂：
后續待補充。
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