Add visual feedback for notification expandability.

Change-Id: I0b82a465a126a6d0ec6cf6af87dc56817765b995

Author: cwren

packages/SystemUI/res/drawable-xhdpi/bottom_divider_glow.png

@@ -4,6 +4,15 @@
     android:background="@*android:drawable/notification_bg"
     >
 
+    <View
+        android:id="@+id/top_glow"
+        android:alpha="0"
+        android:layout_width="match_parent"
+        android:layout_height="@dimen/notification_divider_height"
+        android:layout_gravity="top|center_horizontal"
+        android:background="@drawable/top_divider_glow"
+        />
+
     <Button
         android:id="@+id/veto"
         android:layout_width="48dp"
@@ -19,6 +28,7 @@
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:layout_marginBottom="@dimen/notification_divider_height"
+        android:layout_marginTop="@dimen/notification_divider_height"
         android:focusable="true"
         android:clickable="true"
         >
@@ -31,10 +41,12 @@
     </com.android.systemui.statusbar.LatestItemView>
 
     <View
+        android:id="@+id/bottom_glow"
+        android:alpha="0"
         android:layout_width="match_parent"
         android:layout_height="@dimen/notification_divider_height"
-        android:gravity="bottom"
-        android:background="@*android:drawable/notification_bg"
+        android:layout_gravity="bottom|center_horizontal"
+        android:background="@drawable/bottom_divider_glow"
         />
 
 </FrameLayout>

packages/SystemUI/res/drawable-xhdpi/top_divider_glow.png

@@ -18,9 +18,9 @@
 <resources>
     <!-- thickness (height) of each notification row, including any separators or padding -->
     <!-- Note: this is 64dip + 1px divider = 97px. -->
-    <dimen name="notification_height">97px</dimen>
+    <dimen name="notification_height">99px</dimen>
 
     <!-- thickness (height) of dividers between each notification row; see math for
          notification_height above -->
-    <dimen name="notification_divider_height">1px</dimen>
+    <dimen name="notification_divider_height">4px</dimen>
 </resources>

packages/SystemUI/res/layout/status_bar_notification_row.xml

@@ -19,9 +19,9 @@
     <!-- thickness (height) of each notification row, including any separators or padding -->
     <!-- note: this is the same value as in values/dimens.xml; the value is overridden in
          values-hdpi/dimens.xml and so we need to re-assert the general value here -->
-    <dimen name="notification_height">65dp</dimen>
+    <dimen name="notification_height">68dp</dimen>
 
     <!-- thickness (height) of dividers between each notification row -->
     <!-- same as in values/dimens.xml; see note at notification_height -->
-    <dimen name="notification_divider_height">1dp</dimen>
+    <dimen name="notification_divider_height">2dp</dimen>
 </resources>

packages/SystemUI/res/values-hdpi/dimens.xml

@@ -50,7 +50,7 @@
     <dimen name="navigation_bar_deadzone_size">12dp</dimen>
 
     <!-- thickness (height) of each notification row, including any separators or padding -->
-    <dimen name="notification_height">65dp</dimen>
+    <dimen name="notification_height">68dp</dimen>
 
     <!-- Height of notification icons in the status bar -->
     <dimen name="status_bar_icon_size">@*android:dimen/status_bar_icon_size</dimen>
@@ -72,7 +72,7 @@
     <dimen name="status_bar_icon_padding">0dp</dimen>
 
     <!-- thickness (height) of dividers between each notification row -->
-    <dimen name="notification_divider_height">1dp</dimen>
+    <dimen name="notification_divider_height">4dp</dimen>
 
     <!-- Notification drawer tuning parameters (phone UI) -->
     <!-- Initial velocity of the shade when expanding on its own -->

packages/SystemUI/res/values-xhdpi/dimens.xml

@@ -0,0 +1,20 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+  Copyright (C) 2012 The Android Open Source Project
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+
+<resources>
+    <item type="id" name="expandable_tag" />
+</resources>

packages/SystemUI/res/values/dimens.xml

@@ -32,17 +32,28 @@ public class ExpandHelper implements Gefingerpoken, OnClickListener {
     public interface Callback {
         View getChildAtPosition(MotionEvent ev);
         View getChildAtPosition(float x, float y);
+        boolean canChildBeExpanded(View v);
     }
 
     private static final String TAG = "ExpandHelper";
     protected static final boolean DEBUG = false;
     private static final long EXPAND_DURATION = 250;
 
+    // amount of overstretch for maximum brightness expressed in U
+    // 2f: maximum brightness is stretching a 1U to 3U, or a 4U to 6U
+    private static final float STRETCH_INTERVAL = 2f;
+
+    // level of glow for a touch, without overstretch
+    // overstretch fills the range (GLOW_BASE, 1.0]
+    private static final float GLOW_BASE = 0.5f;
+
     @SuppressWarnings("unused")
     private Context mContext;
 
     private boolean mStretching;
     private View mCurrView;
+    private View mCurrViewTopGlow;
+    private View mCurrViewBottomGlow;
     private float mOldHeight;
     private float mNaturalHeight;
     private float mInitialTouchSpan;
@@ -53,7 +64,7 @@ public interface Callback {
 
     private int mSmallSize;
     private int mLargeSize;
-
+    private float mMaximumStretch;
 
     private class ViewScaler {
         View mView;
@@ -62,7 +73,7 @@ public void setView(View v) {
             mView = v;
         }
         public void setHeight(float h) {
-            Log.v(TAG, "SetHeight: setting to " + h);
+            if (DEBUG) Log.v(TAG, "SetHeight: setting to " + h);
             ViewGroup.LayoutParams lp = mView.getLayoutParams();
             lp.height = (int)h;
             mView.setLayoutParams(lp);
@@ -94,6 +105,7 @@ public int getNaturalHeight(int maximum) {
 
     public ExpandHelper(Context context, Callback callback, int small, int large) {
         mSmallSize = small;
+        mMaximumStretch = mSmallSize * STRETCH_INTERVAL;
         mLargeSize = large;
         mContext = context;
         mCallback = callback;
@@ -120,10 +132,16 @@ public boolean onScale(ScaleGestureDetector detector) {
                 float h = Math.abs(detector.getCurrentSpanY());
                 if (DEBUG) Log.d(TAG, "current span is: " + h);
                 h = h + mOldHeight - mInitialTouchSpan;
+                float target = h;
+                if (DEBUG) Log.d(TAG, "target is: " + target);
                 h = h<mSmallSize?mSmallSize:(h>mLargeSize?mLargeSize:h);
                 h = h>mNaturalHeight?mNaturalHeight:h;
                 if (DEBUG) Log.d(TAG, "scale continues: h=" + h);
                 mScaler.setHeight(h);
+                float stretch = (float) Math.abs((target - h) / mMaximumStretch);
+                float strength = 1f / (1f + (float) Math.pow(Math.E, -1 * ((8f * stretch) - 5f)));
+                if (DEBUG) Log.d(TAG, "stretch: " + stretch + " strength: " + strength);
+                setGlow(GLOW_BASE + strength * (1f - GLOW_BASE));
                 return true;
             }
 
@@ -136,6 +154,14 @@ public void onScaleEnd(ScaleGestureDetector detector) {
             }
         });
     }
+    public void setGlow(float glow) {
+        if (mCurrViewTopGlow != null) {
+            mCurrViewTopGlow.setAlpha(glow);
+        }
+        if (mCurrViewBottomGlow != null) {
+            mCurrViewBottomGlow.setAlpha(glow);
+        }
+    }
 
     public boolean onInterceptTouchEvent(MotionEvent ev) {
         if (DEBUG) Log.d(TAG, "interceptTouch: act=" + (ev.getAction()) +
@@ -154,7 +180,7 @@ public boolean onTouchEvent(MotionEvent ev) {
             case MotionEvent.ACTION_UP:
             case MotionEvent.ACTION_CANCEL:
                 mStretching = false;
-                mCurrView = null;
+                clearView();
                 break;
         }
         return true;
@@ -163,14 +189,20 @@ private boolean initScale(View v) {
         if (v != null) {
             if (DEBUG) Log.d(TAG, "scale begins on view: " + v);
             mStretching = true;
-            mCurrView = v;
+            setView(v);
+            setGlow(GLOW_BASE);
             mScaler.setView(v);
             mOldHeight = mScaler.getHeight();
-            mNaturalHeight = mScaler.getNaturalHeight(mLargeSize);
+            if (mCallback.canChildBeExpanded(v)) {
+                if (DEBUG) Log.d(TAG, "working on an expandable child");
+                mNaturalHeight = mScaler.getNaturalHeight(mLargeSize);
+            } else {
+                if (DEBUG) Log.d(TAG, "working on a non-expandable child");
+                mNaturalHeight = mOldHeight;
+            }
             if (DEBUG) Log.d(TAG, "got mOldHeight: " + mOldHeight +
                         " mNaturalHeight: " + mNaturalHeight);
             v.getParent().requestDisallowInterceptTouchEvent(true);
-            if (DEBUG) v.setBackgroundColor(0xFFFFFF00);
         }
         return mStretching;
     }
@@ -183,11 +215,33 @@ private void finishScale(boolean force) {
         } else {
             h = (force || h < mNaturalHeight) ? mSmallSize : mNaturalHeight;
         }
-        if (DEBUG) mCurrView.setBackgroundColor(0);
+        if (DEBUG && mCurrView != null) mCurrView.setBackgroundColor(0);
         mAnimation = ObjectAnimator.ofFloat(mScaler, "height", h).setDuration(EXPAND_DURATION);
         mAnimation.start();
         mStretching = false;
+        setGlow(0f);
+        clearView();
+    }
+
+    private void clearView() {
         mCurrView = null;
+        mCurrViewTopGlow = null;
+        mCurrViewBottomGlow = null;
+    }
+
+    private void setView(View v) {
+        mCurrView = null;
+        if (v instanceof ViewGroup) {
+            ViewGroup g = (ViewGroup) v;
+            mCurrViewTopGlow = g.findViewById(R.id.top_glow);
+            mCurrViewBottomGlow = g.findViewById(R.id.bottom_glow);
+	    if (DEBUG) {
+                String debugLog = "Looking for glows: " + 
+                        (mCurrViewTopGlow != null ? "found top " : "didn't find top") +
+                        (mCurrViewBottomGlow != null ? "found bottom " : "didn't find bottom");
+                Log.v(TAG,  debugLog);
+            }
+        }
     }
 
     @Override

packages/SystemUI/res/values/ids.xml

@@ -397,12 +397,15 @@ protected  boolean inflateViews(NotificationData.Entry entry, ViewGroup parent)
 
         // XXX: temporary: while testing big notifications, auto-expand all of them
         ViewGroup.LayoutParams lp = row.getLayoutParams();
+        Boolean expandable = Boolean.FALSE;
         if (large != null) {
             lp.height = ViewGroup.LayoutParams.WRAP_CONTENT;
+            expandable = Boolean.TRUE;
         } else {
             lp.height = minHeight;
         }
         row.setLayoutParams(lp);
+        row.setTag(R.id.expandable_tag, expandable);
         workAroundBadLayerDrawableOpacity(row);
         View vetoButton = updateNotificationVetoButton(row, sbn);
         vetoButton.setContentDescription(mContext.getString(

packages/SystemUI/src/com/android/systemui/ExpandHelper.java

@@ -165,6 +165,12 @@ public boolean canChildBeDismissed(View v) {
         return (veto != null && veto.getVisibility() != View.GONE);
     }
 
+    public boolean canChildBeExpanded(View v) {
+        Object isExpandable = v.getTag(R.id.expandable_tag);
+        return isExpandable != null && isExpandable instanceof Boolean &&
+                ((Boolean)isExpandable).booleanValue();
+    }
+
     public void onChildDismissed(View v) {
         final View veto = v.findViewById(R.id.veto);
         if (veto != null && veto.getVisibility() != View.GONE && mRemoveViews) {