fb: Show heads up at the bottom of the screen (1/2)

Due of user requests and indeed especially on hw key devices for a better
workflow we add an option to show heads up notifications on the bottom instead
of the top.

Animation we leave as is due that if it slide from the bottom into the screen it happens
to often that the user accidentaly interacts with it. If it comes from the top of the
container we add, the user has enough time to realize it. Sometimes a ms can make a big difference.

As well this commit fixes the wrong gap on the top if user boots up directly
into immersive mode.

PS:
- if IME keyboard is showing show the heads up on the top to do not disturb the typing.
PS:
- NPE if updatePosition is called to early from the system.

core/java/android/provider/Settings.java

@@ -4641,6 +4641,13 @@ public static void setShowGTalkServiceStatusForUser(ContentResolver cr, boolean
          */
         public static final String APP_SIDEBAR_SHOW_TRIGGER = "app_sidebar_show_trigger";
 
+        /**
+         * Whether heads up notification is shown on the bottom of the screen (default = disabled)
+         *
+         * @hide
+         */
+        public static final String HEADS_UP_GRAVITY_BOTTOM = "heads_up_gravity_bottom";
+
 	/**
 	* Whether heads up notification is expanded by default (default = disabled)
 	*

packages/SystemUI/res/values/probam_dimens.xml

@@ -132,4 +132,7 @@
 
     <!-- Weather -->
     <dimen name="weather_text_margin">56dp</dimen>
+
+    <!-- Heads up -->
+    <dimen name="heads_up_bottom_gap">5dp</dimen>
 </resources>

packages/SystemUI/src/com/android/systemui/statusbar/phone/PhoneStatusBar.java

@@ -330,6 +330,9 @@ public class PhoneStatusBar extends BaseStatusBar implements DemoMode,
     private int mHeadsUpNotificationDecay;
     private boolean mHeadsUpExpandedByDefault;
     private boolean mHeadsUpNotificationViewAttached;
+    private boolean mHeadsUpGravityBottom;
+    private boolean mStatusBarShows = true;
+    private boolean mImeIsShowing;
 
     // on-screen navigation buttons
     private NavigationBarView mNavigationBarView = null;
@@ -472,6 +475,9 @@ void observe() {
             resolver.registerContentObserver(Settings.System.getUriFor(
                 Settings.System.HEADS_UP_SHOW_UPDATE), false, this,
                 UserHandle.USER_ALL);
+            resolver.registerContentObserver(Settings.System.getUriFor(
+                Settings.System.HEADS_UP_GRAVITY_BOTTOM), false, this,
+                UserHandle.USER_ALL);
 
             updateSettings();
         }
@@ -912,6 +918,14 @@ public boolean onTouch(View v, MotionEvent event) {
                 mContext.getContentResolver(),
                 Settings.System.HEADS_UP_SHOW_UPDATE, 0,
                 UserHandle.USER_CURRENT) == 1;
+        mHeadsUpGravityBottom = Settings.System.getIntForUser(
+                mContext.getContentResolver(),
+                Settings.System.HEADS_UP_GRAVITY_BOTTOM, 0,
+                UserHandle.USER_CURRENT) == 1;
+        mHeadsUpGravityBottom = Settings.System.getIntForUser(
+                mContext.getContentResolver(),
+                Settings.System.HEADS_UP_GRAVITY_BOTTOM, 0,
+                UserHandle.USER_CURRENT) == 1;
 
         if (MULTIUSER_DEBUG) {
             mNotificationPanelDebugText = (TextView) mNotificationPanel.findViewById(R.id.header_debug_info);
@@ -1480,6 +1494,10 @@ public void onClick(View v) {
         }
     };
 
+    private int getBottomGap() {
+        return mContext.getResources().getDimensionPixelSize(R.dimen.heads_up_bottom_gap);
+    }
+
     private int mShowSearchHoldoff = 0;
     private Runnable mShowSearchPanel = new Runnable() {
         public void run() {
@@ -1611,8 +1629,9 @@ private void addHeadsUpView() {
         if (ActivityManager.isHighEndGfx()) {
             lp.flags |= WindowManager.LayoutParams.FLAG_HARDWARE_ACCELERATED;
         }
-        lp.gravity = Gravity.TOP;
-        lp.y = getStatusBarHeight();
+        lp.gravity = mHeadsUpGravityBottom && !mImeIsShowing ? Gravity.BOTTOM : Gravity.TOP;
+        lp.y = mHeadsUpGravityBottom && !mImeIsShowing
+                ? getBottomGap() : (mStatusBarShows ? getStatusBarHeight() : 0);
         lp.setTitle("Heads Up");
         lp.packageName = mContext.getPackageName();
         lp.windowAnimations = R.style.Animation_StatusBar_HeadsUp;
@@ -1744,6 +1763,7 @@ public void hideHeadsUp() {
 
     @Override // CommandQueue
     public void updateHeadsUpPosition(boolean statusBarShows) {
+        mStatusBarShows = statusBarShows;
         // Change y layoutparams of heads up view when statusbar
         // visibility changes.
         // ToDo: We may want to animate this in future in the rare
@@ -1755,9 +1775,13 @@ public void updateHeadsUpPosition(boolean statusBarShows) {
         if (mHeadsUpNotificationView != null) {
             WindowManager.LayoutParams lp = (WindowManager.LayoutParams)
                     mHeadsUpNotificationView.getLayoutParams();
-            lp.y = statusBarShows ? getStatusBarHeight() : 0;
-            mWindowManager.updateViewLayout(mHeadsUpNotificationView, lp);
-       }
+            if (lp != null) {
+                lp.gravity = mHeadsUpGravityBottom && !mImeIsShowing ? Gravity.BOTTOM : Gravity.TOP;
+                lp.y = mHeadsUpGravityBottom && !mImeIsShowing
+                        ? getBottomGap() : (mStatusBarShows ? getStatusBarHeight() : 0);
+                mWindowManager.updateViewLayout(mHeadsUpNotificationView, lp);
+            }
+        }
     }
 
     public void removeNotification(IBinder key) {
@@ -3142,6 +3166,12 @@ public void setImeWindowStatus(IBinder token, int vis, int backDisposition) {
         boolean altBack = (backDisposition == InputMethodService.BACK_DISPOSITION_WILL_DISMISS)
             || mImeShowing;
 
+        // If IME shows and heads up gravity is at the bottom, move it to the top.
+        if (mImeIsShowing != altBack) {
+            mImeIsShowing = altBack;
+            updateHeadsUpPosition(mStatusBarShows);
+        }
+
         setNavigationIconHints(
                 altBack ? (mNavigationIconHints | NAVIGATION_HINT_BACK_ALT)
                         : (mNavigationIconHints & ~NAVIGATION_HINT_BACK_ALT));
@@ -4457,6 +4487,13 @@ public void onChange(boolean selfChange, Uri uri) {
                             mContext.getContentResolver(),
                             Settings.System.HEADS_UP_SHOW_UPDATE, 0,
                             UserHandle.USER_CURRENT) == 1;
+            } else if (uri.equals(Settings.System.getUriFor(
+                Settings.System.HEADS_UP_GRAVITY_BOTTOM))) {
+                mHeadsUpGravityBottom = Settings.System.getIntForUser(
+                    mContext.getContentResolver(),
+                    Settings.System.HEADS_UP_GRAVITY_BOTTOM, 0,
+                    UserHandle.USER_CURRENT) == 1;
+                updateHeadsUpPosition(mStatusBarShows);
             }
             updateSettings();
 	    }