Speed up user-switching wallpaper changes
Previous work in ImageWallpaper cached the bitmap for a user
to avoid reloading it (an expensive operation on large-display devices)
when we could simply re-use it. User switching still caused a reload, however,
since the place where we cache the bitmap (ImageWallpaper) is in an instance
that is re-created on user-switch.
A simple fix is to have the ImageWallpaper stop telling the WallpaperManager
to erase its own cache of the bitmap prior to re-loading it. That step is
unnecessary, since a bitmap that is cached can be assumed to be valid. A wallpaper
change will correctly null out that cached version, so if the cached bitmap
is non-null, then we can simply use it as-is.
The fix is to remove the call to forgetLoadedWallpaper() and allow the caching
mechanism to do its job.
Issue #7986933 user switching on lock screen is slow (sometimes like molasses)
Change-Id: I447754ab85337bc8ae59b4ad6c3e6c2b30e13735
diff --git a/packages/SystemUI/src/com/android/systemui/ImageWallpaper.java b/packages/SystemUI/src/com/android/systemui/ImageWallpaper.java
index 627235f..cdd3d84 100644
--- a/packages/SystemUI/src/com/android/systemui/ImageWallpaper.java
+++ b/packages/SystemUI/src/com/android/systemui/ImageWallpaper.java
@@ -388,7 +388,6 @@
private void updateWallpaperLocked() {
Throwable exception = null;
try {
- mWallpaperManager.forgetLoadedWallpaper(); // force reload
mBackground = null;
mBackground = mWallpaperManager.getBitmap();
} catch (RuntimeException e) {