Add edgeEffectType attribute and type property

Bug: 178807038

This adds the edgeEffectType property and
type attribute. These will be used to
enable stretchy edge effect for overscroll.

Merged-In: I16f20b36d9a15c08e0a37f98572ef9c9f8fbc88f
Test: new CTS test for setting/retrieving the effect type.
Test: Ic363f71d241649d15faa86434516457e62b261f4
Change-Id: I16f20b36d9a15c08e0a37f98572ef9c9f8fbc88f

core/api/current.txt

@@ -573,6 +573,7 @@ package android {
     field public static final int dropDownWidth = 16843362; // 0x1010262
     field public static final int duplicateParentState = 16842985; // 0x10100e9
     field public static final int duration = 16843160; // 0x1010198
+    field public static final int edgeEffectType = 16844329; // 0x1010629
     field public static final int editTextBackground = 16843602; // 0x1010352
     field public static final int editTextColor = 16843601; // 0x1010351
     field public static final int editTextPreferenceStyle = 16842898; // 0x1010092
@@ -53561,6 +53562,7 @@ package android.widget {
     method @Nullable public android.graphics.BlendMode getBlendMode();
     method @ColorInt public int getColor();
     method public int getMaxHeight();
+    method public int getType();
     method public boolean isFinished();
     method public void onAbsorb(int);
     method public void onPull(float);
@@ -53569,7 +53571,10 @@ package android.widget {
     method public void setBlendMode(@Nullable android.graphics.BlendMode);
     method public void setColor(@ColorInt int);
     method public void setSize(int, int);
+    method public void setType(int);
     field public static final android.graphics.BlendMode DEFAULT_BLEND_MODE;
+    field public static final int TYPE_GLOW = 0; // 0x0
+    field public static final int TYPE_STRETCH = 1; // 0x1
   }
 
   public class EditText extends android.widget.TextView {

core/java/android/widget/EdgeEffect.java

@@ -17,6 +17,7 @@
 package android.widget;
 
 import android.annotation.ColorInt;
+import android.annotation.IntDef;
 import android.annotation.Nullable;
 import android.compat.annotation.UnsupportedAppUsage;
 import android.content.Context;
@@ -30,6 +31,9 @@ import android.view.animation.AnimationUtils;
 import android.view.animation.DecelerateInterpolator;
 import android.view.animation.Interpolator;
 
+import java.lang.annotation.Retention;
+import java.lang.annotation.RetentionPolicy;
+
 /**
  * This class performs the graphical effect used at the edges of scrollable widgets
  * when the user scrolls beyond the content bounds in 2D space.
@@ -55,6 +59,24 @@ public class EdgeEffect {
      */
     public static final BlendMode DEFAULT_BLEND_MODE = BlendMode.SRC_ATOP;
 
+    /**
+     * Use a color edge glow for the edge effect. From XML, use
+     * <code>android:edgeEffectType="glow"</code>.
+     */
+    public static final int TYPE_GLOW = 0;
+
+    /**
+     * Use a stretch for the edge effect. From XML, use
+     * <code>android:edgeEffectType="stretch"</code>.
+     */
+    public static final int TYPE_STRETCH = 1;
+
+    /** @hide */
+    @IntDef({TYPE_GLOW, TYPE_STRETCH})
+    @Retention(RetentionPolicy.SOURCE)
+    public @interface EdgeEffectType {
+    }
+
     @SuppressWarnings("UnusedDeclaration")
     private static final String TAG = "EdgeEffect";
 
@@ -121,6 +143,7 @@ public class EdgeEffect {
     private float mBaseGlowScale;
     private float mDisplacement = 0.5f;
     private float mTargetDisplacement = 0.5f;
+    private @EdgeEffectType int mEdgeEffectType = TYPE_GLOW;
 
     /**
      * Construct a new EdgeEffect with a theme appropriate for the provided context.
@@ -132,6 +155,8 @@ public class EdgeEffect {
                 com.android.internal.R.styleable.EdgeEffect);
         final int themeColor = a.getColor(
                 com.android.internal.R.styleable.EdgeEffect_colorEdgeEffect, 0xff666666);
+        mEdgeEffectType = a.getInt(
+                com.android.internal.R.styleable.EdgeEffect_edgeEffectType, TYPE_GLOW);
         a.recycle();
         mPaint.setColor((themeColor & 0xffffff) | 0x33000000);
         mPaint.setStyle(Paint.Style.FILL);
@@ -308,6 +333,17 @@ public class EdgeEffect {
         mPaint.setColor(color);
     }
 
+    /**
+     * Sets the edge effect type to use. The default without a theme attribute set is
+     * {@link EdgeEffect#TYPE_GLOW}.
+     *
+     * @param type The edge effect type to use.
+     * @attr ref android.R.styleable#EdgeEffect_edgeEffectType
+     */
+    public void setType(@EdgeEffectType int type) {
+        mEdgeEffectType = type;
+    }
+
     /**
      * Set or clear the blend mode. A blend mode defines how source pixels
      * (generated by a drawing command) are composited with the destination pixels
@@ -333,6 +369,15 @@ public class EdgeEffect {
         return mPaint.getColor();
     }
 
+    /**
+     * Return the edge effect type to use.
+     *
+     * @return The edge effect type to use.
+     * @attr ref android.R.styleable#EdgeEffect_edgeEffectType
+     */
+    public @EdgeEffectType int getType() {
+        return mEdgeEffectType;
+    }
 
     /**
      * Returns the blend mode. A blend mode defines how source pixels

core/res/res/values/attrs.xml

@@ -1140,6 +1140,15 @@
         <!-- The color applied to the edge effect on scrolling containers. -->
         <attr name="colorEdgeEffect" format="color" />
 
+        <!-- The type of the edge effect. The default is glow. -->
+        <attr name="edgeEffectType">
+            <!-- Use a colored glow at the edge. -->
+            <enum name="glow" value="0" />
+
+            <!-- Stretch the content. -->
+            <enum name="stretch" value="1" />
+        </attr>
+
         <!-- =================== -->
         <!-- Lighting properties -->
         <!-- =================== -->
@@ -9050,6 +9059,7 @@
     <!-- Used as a filter array on the theme to pull out only the EdgeEffect-relevant bits. -->
     <declare-styleable name="EdgeEffect">
         <attr name="colorEdgeEffect" />
+        <attr name="edgeEffectType" />
     </declare-styleable>
 
     <!-- Use <code>tv-input</code> as the root tag of the XML resource that describes a

core/res/res/values/public.xml

@@ -3063,6 +3063,7 @@
     <public name="hotwordDetectionService" />
     <public name="previewLayout" />
     <public name="clipToOutline" />
+    <public name="edgeEffectType" />
   </public-group>
 
   <public-group type="drawable" first-id="0x010800b5">