adroid 5.1鎖屏研究總結

Android 5.1 和6.0的鎖屏和以往的版本相比發生了很大變化，同時增加了新的特性：鎖屏上顯示通知。另一方面，Keyguard 不在是獨立的apk和systemUI 合併，做成了systemUI的一個lib ，如下Android.mk可以說明

Android 4.4 --SystemUI--Android.mk

<span style="font-size:14px;font-weight: normal;">LOCAL_JAVA_LIBRARIES := telephony-common
LOCAL_PACKAGE_NAME := SystemUI
LOCAL_CERTIFICATE := platform
LOCAL_PRIVILEGED_MODULE := true
LOCAL_PROGUARD_FLAG_FILES := proguard.flags
include $(BUILD_PACKAGE)
include $(call all-makefiles-under,$(LOCAL_PATH))</span>

Android5.1 systemUI Android.mk

<span style="font-weight: normal;">LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)
LOCAL_MODULE_TAGS := optional
LOCAL_SRC_FILES := $(call all-java-files-under, src) \
    src/com/android/systemui/EventLogTags.logtags
LOCAL_STATIC_JAVA_LIBRARIES := Keyguard
LOCAL_JAVA_LIBRARIES := telephony-common telephony-common2
LOCAL_PACKAGE_NAME := SystemUI
LOCAL_CERTIFICATE := platform
LOCAL_PRIVILEGED_MODULE := true
LOCAL_PROGUARD_FLAG_FILES := proguard.flags
LOCAL_RESOURCE_DIR := \
    frameworks/base/packages/Keyguard/res \
    $(LOCAL_PATH)/res
LOCAL_AAPT_FLAGS := --auto-add-overlay --extra-packages com.android.keyguard
include $(BUILD_PACKAGE)
include $(call all-makefiles-under,$(LOCAL_PATH))</span>

Adroid6.0 systemUI Android.mk

LOCAL_PATH:= $(call my-dir)
include $(CLEAR_VARS)

LOCAL_MODULE_TAGS := optional

LOCAL_SRC_FILES := $(call all-java-files-under, src) \
    src/com/android/systemui/EventLogTags.logtags

LOCAL_STATIC_JAVA_LIBRARIES := Keyguard
LOCAL_JAVA_LIBRARIES := telephony-common ims-common

LOCAL_PACKAGE_NAME := SystemUI
LOCAL_CERTIFICATE := platform
LOCAL_PRIVILEGED_MODULE := true

LOCAL_PROGUARD_FLAG_FILES := proguard.flags

LOCAL_RESOURCE_DIR := \
    frameworks/base/packages/Keyguard/res \
    $(LOCAL_PATH)/res
LOCAL_AAPT_FLAGS := --auto-add-overlay --extra-packages com.android.keyguard

ifneq ($(SYSTEM_UI_INCREMENTAL_BUILDS),)
    LOCAL_PROGUARD_ENABLED := disabled
    LOCAL_JACK_ENABLED := incremental
endif

include frameworks/base/packages/SettingsLib/common.mk

include $(BUILD_PACKAGE)

ifeq ($(EXCLUDE_SYSTEMUI_TESTS),)
    include $(call all-makefiles-under,$(LOCAL_PATH))
endif

對比上面既可以發現，差別顯而易見，其中

LOCAL_STATIC_JAVA_LIBRARIES := Keyguard #表示Keyguard是一個static lib。

LOCAL_AAPT_FLAGS := --auto-add-overlay --extra-packages com.android.keyguard #表示Keyguard 和 SystemUI被整合到一起，這樣修改源碼代碼以後，只要mm SystemUI。

Android4.4上，show Keyguard，KeyguardViewManager.java和KeyguardHostView.java比較重要，而在Android5.1上，這兩者直接被棄用了，Android5.1 Keyguard的root view是SystemUI下的StatusBarWindowView,KeyguardViewManager也被StatusBarKeyguardViewManager所取代，StatusBarKeyguardViewManager現在負責管理keyguard 在status bar中

創建、顯示、隱藏、重置。show keyguard 有兩個觸發點，一個是systemReady,意思是系統啓動完成以後show keyguard。另一個是screenOff，表示滅屏，手機要滅屏進入休眠狀態有兩個原因：手動按Power鍵滅屏（WindowManagerPolicy.OFF_BECAUSE_OF_USER）和系統自動滅屏（WindowManagerPolicy.OFF_BECAUSE_OF_TIMEOUT）。

SystemReady 顯示鎖屏大致流程圖：

screen off 顯示大致流程：

從流程上看，在決定顯示keygurad的時，還會判斷顯示 Bouncer 還是Keygurad：（StatusBarKeyguardViewManager.java）

/**
* Shows the notification keyguard or the bouncer depending on
* {@link KeyguardBouncer#needsFullscreenBouncer()}.
*/
private void showBouncerOrKeyguard() {
if (mBouncer.needsFullscreenBouncer()) {

// The keyguard might be showing (already). So we need to hide it.
mPhoneStatusBar.hideKeyguard();
mBouncer.show(true /* resetSecuritySelection */);
} else {
mPhoneStatusBar.showKeyguard();
mBouncer.hide(false /* destroyView */);
mBouncer.prepare();
}
}

Bouncer是用來顯示安全鎖屏，比如圖案鎖屏、密碼鎖屏、PIN碼鎖屏等，

從代碼中可以看出，show Bouncer的時候纔會調用到Keygurad那邊的KeyguardViewBase來show Security Screen，（eyguardBouncer.java）

public void show(boolean resetSecuritySelection) {
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;
}

// Try to dismiss the Keyguard. If no security pattern is set, this will dismiss the whole
// Keyguard. If we need to authenticate, show the bouncer.
if (!mKeyguardView.dismiss()) {
mShowingSoon = true;

// Split up the work over multiple frames.
mChoreographer.postCallbackDelayed(Choreographer.CALLBACK_ANIMATION, mShowRunnable,
null, 16);
}
}

下面安全鎖屏跟以前基本相同，而普通的鎖屏和StatusBar 融合到了一塊(PhoneStatusBar.java)

public void showKeyguard() {
if (mLaunchTransitionFadingAway) {
mNotificationPanel.animate().cancel();
mNotificationPanel.setAlpha(1f);
runLaunchTransitionEndRunnable();
mLaunchTransitionFadingAway = false;
}
mHandler.removeMessages(MSG_LAUNCH_TRANSITION_TIMEOUT);
setBarState(StatusBarState.KEYGUARD);
updateKeyguardState(false /* goingToFullShade */, false /* fromShadeLocked */);
if (!mScreenOnFromKeyguard) {
// If the screen is off already, we need to disable touch events because these might
// collapse the panel after we expanded it, and thus we would end up with a blank
// Keyguard.
mNotificationPanel.setTouchDisabled(true);
}
instantExpandNotificationsPanel();
mLeaveOpenOnKeyguardHide = false;
if (mDraggedDownRow != null) {
mDraggedDownRow.setUserLocked(false);
mDraggedDownRow.notifyHeightChanged();
mDraggedDownRow = null;
}
}

從showKeyguard()方法中可以看到，並沒有addView() 和 TYPE_KEYGUARD。而只是setBarState(StatusBarState.KEYGUARD)。

/**
* Class to encapsulate all possible status bar states regarding Keyguard.
*/
public class StatusBarState {
/**
* The status bar is in the "normal" shade mode.
*/
public static final int SHADE = 0;
/**
* Status bar is currently the Keyguard.
*/
public static final int KEYGUARD = 1;
/**
* Status bar is in the special mode, where it is fully interactive but still locked. So
* dismissing the shade will still show the bouncer.
*/
public static final int SHADE_LOCKED = 2;
}

說到TYPE_KEYGUARD，在Android5.1版本中並沒有使用這個window type來show keyguard，而是使用PRIVATE_FLAG_KEYGUARD。

private void applyKeyguardFlags(State state) {
if (state.keyguardShowing) {
mLpChanged.flags |= WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
mLpChanged.privateFlags |= WindowManager.LayoutParams.PRIVATE_FLAG_KEYGUARD;
} else {
mLpChanged.flags &= ~WindowManager.LayoutParams.FLAG_SHOW_WALLPAPER;
mLpChanged.privateFlags &= ~WindowManager.LayoutParams.PRIVATE_FLAG_KEYGUARD;
}
}

鎖屏上增加了Notification，在鎖屏是否顯示Notification，這個在設置中可以設置。

SystemUI通過監聽設置決定是否顯示Notification，這部分邏輯在BaseStatusBar.java中。

public void start() {
...
mContext.getContentResolver().registerContentObserver(
Settings.Secure.getUriFor(Settings.Secure.LOCK_SCREEN_SHOW_NOTIFICATIONS), false,
mSettingsObserver,
UserHandle.USER_ALL);

mContext.getContentResolver().registerContentObserver(
Settings.Secure.getUriFor(Settings.Secure.LOCK_SCREEN_ALLOW_PRIVATE_NOTIFICATIONS),
true,
mLockscreenSettingsObserver,
UserHandle.USER_ALL);
...
}

protected final ContentObserver mSettingsObserver = new ContentObserver(mHandler) {
@Override
public void onChange(boolean selfChange) {
final boolean provisioned = 0 != Settings.Global.getInt(
mContext.getContentResolver(), Settings.Global.DEVICE_PROVISIONED, 0);
if (provisioned != mDeviceProvisioned) {
mDeviceProvisioned = provisioned;
updateNotifications();
}
final int mode = Settings.Global.getInt(mContext.getContentResolver(),
Settings.Global.ZEN_MODE, Settings.Global.ZEN_MODE_OFF);
setZenMode(mode);

updateLockscreenNotificationSetting();
}
};

private final ContentObserver mLockscreenSettingsObserver = new ContentObserver(mHandler) {
@Override
public void onChange(boolean selfChange) {
// We don't know which user changed LOCK_SCREEN_ALLOW_PRIVATE_NOTIFICATIONS,
// so we just dump our cache ...
mUsersAllowingPrivateNotifications.clear();
// ... and refresh all the notifications
updateNotifications();
}
};

Android 6.0還沒有仔細研究，以後補充。。。