Android 12中系统Wallpaper详解1

您所在的位置:网站首页 简约壁纸图片锁屏和桌面不一样 Android 12中系统Wallpaper详解1

Android 12中系统Wallpaper详解1

2024-07-11 15:17| 来源: 网络整理| 查看: 265

1 桌面壁纸

先看桌面情况下壁纸,这个情况应该属于我们最为熟悉的,那么就不用多说,大概就是因为桌面Activity的配置主题xml设置一个类似showallpaper的属性既可以,就可以让桌面后面显示壁纸了 在这里插入图片描述

2 aosp编译后版本锁屏后点亮屏幕也可以看到桌面壁纸(注意这里还不是专门锁屏壁纸) 大家发现锁屏点亮后确实看到的壁纸和桌面的壁纸一模一样 在这里插入图片描述

3 疑惑

这里是不是大家就开始比较疑惑了,请问普通Activity是通过属性配置的,而且壁纸窗口又是在wms属于最底层的状态,他依附于桌面这个可以理解,但是为啥锁屏时候又可以看到壁纸呢?锁屏理论上也只是一个window盖在最顶层,理论即使这个锁屏window透明,那么透看到的也是有桌面Activity的情况,但现实情况是我们只看到了壁纸,并没有看到桌面

针对以上的疑惑,那接下来我们就需要去解答这个疑惑。 首先我们知道壁纸属于系统中一个特殊窗口,一直处于系统最底层。这个窗口在系统中有专门类进行他的显示情况,那就我们的WallpaperController类 这个WallpaperController.java中有log打印,但需要我们将对应标志位给设置一下:

if (DEBUG_WALLPAPER) { Slog.v(TAG, "Wallpaper visibility: " + visible + " at display " + mDisplayContent.getDisplayId()); }

这里我们把DEBUG_WALLPAPER就可以把log打开了

10-23 22:55:41.115 5313 6475 V WindowManager: Win Window{60c77f1 u0 ScreenDecorOverlayBottom}: isOnScreen=true mDrawState=4 10-23 22:55:41.115 5313 6475 V WindowManager: Win Window{df0a78b u0 ScreenDecorOverlay}: isOnScreen=true mDrawState=4 10-23 22:55:41.115 5313 6475 V WindowManager: Win Window{b7a35a u0 NavigationBar0}: isOnScreen=true mDrawState=4 10-23 22:55:41.115 5313 6475 V WindowManager: Win Window{3cd76e8 u0 NotificationShade}: isOnScreen=true mDrawState=4 10-23 22:55:41.115 5313 6475 V WindowManager: Found wallpaper target: Window{3cd76e8 u0 NotificationShade} 10-23 22:55:41.115 5313 6475 V WindowManager: New wallpaper target: Window{3cd76e8 u0 NotificationShade} prevTarget: null 10-23 22:55:41.116 5313 6475 V WindowManager: Report new wp offset Window{803c2b8 u0 com.android.systemui.ImageWallpaper} x=0.0 y=0.5 zoom=0.0 10-23 22:55:41.116 5313 6475 V WindowManager: Wallpaper visibility: true at display 0 10-23 22:55:41.116 5313 6475 D WindowManager: Wallpaper token android.os.Binder@3a6eda2 visible=true 10-23 22:55:41.118 5313 6475 D WindowManager: New wallpaper: target=Window{3cd76e8 u0 NotificationShade} prev=null 10-23 22:55:41.163 5313 5313 D WindowManager: powerPress: eventTime=118823847 interactive=true count=0 beganFromNonInteractive=true mShortPressOnPowerBehavior=1

打开后我们点亮锁屏和在桌面锁屏发现都有类似以下打印 WindowManager: Found wallpaper target: Window{3cd76e8 u0 NotificationShade} 看名字大家大概就知道这个log是在寻找一个wallpaper target:,而且找到的是NotificationShade即锁屏窗口 前面疑惑中就写到正常应该是桌面 10-24 00:18:50.543 10429 10450 V WindowManager: Found wallpaper target: Window{8d79f3 u0 com.android.launcher3/com.android.launcher3.uioverrides.QuickstepLauncher} 这日志其实就可以给我们非常重要线索,可以找出对应代码在哪

private final ToBooleanFunction mFindWallpaperTargetFunction = w -> { if ((w.mAttrs.type == TYPE_WALLPAPER)) { if (mFindResults.topWallpaper == null || mFindResults.resetTopWallpaper) { mFindResults.setTopWallpaper(w); mFindResults.resetTopWallpaper = false; } return false; } mFindResults.resetTopWallpaper = true; if (mService.mAtmService.getTransitionController().getTransitionPlayer() == null) { if (w.mActivityRecord != null && !w.mActivityRecord.isVisible() && !w.mActivityRecord.isAnimating(TRANSITION | PARENTS)) { // If this window's app token is hidden and not animating, it is of no interest. if (DEBUG_WALLPAPER) Slog.v(TAG, "Skipping hidden and not animating token: " + w); return false; } } else { if (w.mActivityRecord != null && !w.mActivityRecord.isVisibleRequested()) { // An activity that is not going to remain visible shouldn't be the target. return false; } } if (DEBUG_WALLPAPER) Slog.v(TAG, "Win " + w + ": isOnScreen=" + w.isOnScreen() + " mDrawState=" + w.mWinAnimator.mDrawState + " w.mWillReplaceWindow = " + w.mWillReplaceWindow); if (w.toString().contains("NotificationShade")) { Slog.v(TAG, "1111 Win " + w + ": isOnScreen=" + w.isOnScreen() + " mDrawState=" + w.mWinAnimator.mDrawState + " w.mWillReplaceWindow = " + w.mWillReplaceWindow); } if (w.mWillReplaceWindow && mWallpaperTarget == null && !mFindResults.useTopWallpaperAsTarget) { // When we are replacing a window and there was wallpaper before replacement, we want to // keep the window until the new windows fully appear and can determine the visibility, // to avoid flickering. mFindResults.setUseTopWallpaperAsTarget(true); } final WindowContainer animatingContainer = w.mActivityRecord != null ? w.mActivityRecord.getAnimatingContainer() : null; final boolean keyguardGoingAwayWithWallpaper = (animatingContainer != null && animatingContainer.isAnimating(TRANSITION | PARENTS) && AppTransition.isKeyguardGoingAwayTransitOld(animatingContainer.mTransit) && (animatingContainer.mTransitFlags & TRANSIT_FLAG_KEYGUARD_GOING_AWAY_WITH_WALLPAPER) != 0); boolean needsShowWhenLockedWallpaper = false; if ((w.mAttrs.flags & FLAG_SHOW_WHEN_LOCKED) != 0 && mService.mPolicy.isKeyguardLocked() && (mService.mPolicy.isKeyguardOccluded() || mService.mPolicy.isKeyguardUnoccluding())) { // The lowest show when locked window decides whether we need to put the wallpaper // behind. needsShowWhenLockedWallpaper = !isFullscreen(w.mAttrs) || (w.mActivityRecord != null && !w.mActivityRecord.fillsParent()); } if (keyguardGoingAwayWithWallpaper || needsShowWhenLockedWallpaper) { // Keep the wallpaper during Keyguard exit but also when it's needed for a // non-fullscreen show when locked activity. mFindResults.setUseTopWallpaperAsTarget(true); } final RecentsAnimationController recentsAnimationController = mService.getRecentsAnimationController(); final boolean animationWallpaper = animatingContainer != null && animatingContainer.getAnimation() != null && animatingContainer.getAnimation().getShowWallpaper(); final boolean hasWallpaper = w.hasWallpaper() || animationWallpaper; final boolean isRecentsTransitionTarget = (recentsAnimationController != null && recentsAnimationController.isWallpaperVisible(w)); if (isRecentsTransitionTarget) { if (DEBUG_WALLPAPER) Slog.v(TAG, "Found recents animation wallpaper target: " + w); mFindResults.setWallpaperTarget(w); return true; } else if (hasWallpaper && w.isOnScreen() && (mWallpaperTarget == w || w.isDrawFinishedLw())) { if (DEBUG_WALLPAPER) Slog.v(TAG, "Found wallpaper target: " + w); mFindResults.setWallpaperTarget(w); if (w == mWallpaperTarget && w.isAnimating(TRANSITION | PARENTS)) { // The current wallpaper target is animating, so we'll look behind it for // another possible target and figure out what is going on later. if (DEBUG_WALLPAPER) Slog.v(TAG, "Win " + w + ": token animating, looking behind."); } // Found a target! End search. return true; } return false; };

上面最关键判断代码:

if (hasWallpaper && w.isOnScreen() && (mWallpaperTarget == w || w.isDrawFinishedLw()))

这里的 hasWallpaper非常关键

final boolean hasWallpaper = w.hasWallpaper() || animationWallpaper;

主要调用是WindowState的方法

boolean hasWallpaper() { return (mAttrs.flags & FLAG_SHOW_WALLPAPER) != 0 || (mActivityRecord != null && mActivityRecord.hasWallpaperBackgroudForLetterbox()); }

这里其实也就是判断window中是否有FLAG_SHOW_WALLPAPER属性,而且经过额外加log打印发现hasWallpaper值变化在锁屏window解锁前后

那么其实我们可以猜测是不是锁屏window会去动态改变自己的FLAG_SHOW_WALLPAPER属性,在有桌面显示时候锁屏的window实际是没有这个属性,在锁屏状态下是有这个属性。根据猜想去systemui代码中grep相关FLAG_SHOW_WALLPAPER关键字 果然发现有如下: frameworks/base/packages/SystemUI/src/com/android/systemui/statusbar/phone/NotificationShadeWindowControllerImpl.java

private void applyKeyguardFlags(State state) { final boolean scrimsOccludingWallpaper = state.mScrimsVisibility == ScrimController.OPAQUE || state.mLightRevealScrimOpaque; final boolean keyguardOrAod = state.mKeyguardShowing || (state.mDozing && mDozeParameters.getAlwaysOn()); if ((keyguardOrAod && !state.mBackdropShowing && !scrimsOccludingWallpaper) || mKeyguardViewMediator.isAnimatingBetweenKeyguardAndSurfaceBehindOrWillBe()) { // Show the wallpaper if we're on keyguard/AOD and the wallpaper is not occluded by a // solid backdrop or scrim. Also, show it if we are currently animating between the // keyguard and the surface behind the keyguard - we want to use the wallpaper as a // backdrop for this animation. mLpChanged.flags |= LayoutParams.FLAG_SHOW_WALLPAPER; } else { mLpChanged.flags &= ~LayoutParams.FLAG_SHOW_WALLPAPER; }

这里其实就是代表有锁屏时候需要有 mLpChanged.flags |= LayoutParams.FLAG_SHOW_WALLPAPER; 锁屏退出时清除锁屏的FLAG_SHOW_WALLPAPER mLpChanged.flags &= ~LayoutParams.FLAG_SHOW_WALLPAPER;



【本文地址】


今日新闻


推荐新闻


CopyRight 2018-2019 办公设备维修网 版权所有 豫ICP备15022753号-3