Have the stable layout take into account the window's fullscreen flag.
When using stable layouts, you are typically expected to hide and
show the status bar through the system UI fullscreen flag. This hides
both the status bar and the action bar. The stable layout assumed
that when not hiding the status bar through the system UI flags, that
the status bar would be visible.
This change makes things a little smarter, also looking at the
window's fullscreen flag (which only hides the status bar). If this
flag is set on the window, then the stable layout now assumes that
the status bar will never be shown. This allows us to position the
action bar correctly in the situation where the application has set
the window to fullscreen and requested a stable layout, instead of
always leaving room for the status bar above it.
Change-Id: I757072ae99cd3741753af7210dbf51afe94d3db5
diff --git a/core/java/android/view/View.java b/core/java/android/view/View.java
index a4fcd41..b73b093 100644
--- a/core/java/android/view/View.java
+++ b/core/java/android/view/View.java
@@ -2255,9 +2255,27 @@
* flags, we would like a stable view of the content insets given to
* {@link #fitSystemWindows(Rect)}. This means that the insets seen there
* will always represent the worst case that the application can expect
- * as a continue state. In practice this means with any of system bar,
- * nav bar, and status bar shown, but not the space that would be needed
- * for an input method.
+ * as a continuous state. In the stock Android UI this is the space for
+ * the system bar, nav bar, and status bar, but not more transient elements
+ * such as an input method.
+ *
+ * The stable layout your UI sees is based on the system UI modes you can
+ * switch to. That is, if you specify {@link #SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN}
+ * then you will get a stable layout for changes of the
+ * {@link #SYSTEM_UI_FLAG_FULLSCREEN} mode; if you specify
+ * {@link #SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN} and
+ * {@link #SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION}, then you can transition
+ * to {@link #SYSTEM_UI_FLAG_FULLSCREEN} and {@link #SYSTEM_UI_FLAG_HIDE_NAVIGATION}
+ * with a stable layout. (Note that you should avoid using
+ * {@link #SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION} by itself.)
+ *
+ * If you have set the window flag {@ WindowManager.LayoutParams#FLAG_FULLSCREEN}
+ * to hide the status bar (instead of using {@link #SYSTEM_UI_FLAG_FULLSCREEN}),
+ * then a hidden status bar will be considered a "stable" state for purposes
+ * here. This allows your UI to continually hide the status bar, while still
+ * using the system UI flags to hide the action bar while still retaining
+ * a stable layout. Note that changing the window fullscreen flag will never
+ * provide a stable layout for a clean transition.
*
* <p>If you are using ActionBar in
* overlay mode with {@link Window#FEATURE_ACTION_BAR_OVERLAY