Make ExploreSites IPH pulse cover as large an area as possible

Bug: 977621
Change-Id: I78bfea20233d63b97dd48fd7cb6377476940ea3e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1698984
Commit-Queue: Cathy Li <chili@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#683346}

chrome/android/java/src/org/chromium/chrome/browser/explore_sites/ExploreSitesIPH.java

@@ -5,11 +5,13 @@
 package org.chromium.chrome.browser.explore_sites;
 
 import android.content.Context;
+import android.graphics.Rect;
 import android.view.View;
 
 import org.chromium.chrome.browser.ChromeActivity;
 import org.chromium.chrome.browser.feature_engagement.TrackerFactory;
 import org.chromium.chrome.browser.profiles.Profile;
+import org.chromium.chrome.browser.widget.PulseDrawable;
 import org.chromium.chrome.browser.widget.ViewHighlighter;
 import org.chromium.chrome.browser.widget.textbubble.TextBubble;
 import org.chromium.chrome.browser.widget.tile.TileView;
@@ -63,7 +65,23 @@ public class ExploreSitesIPH {
                 accessibilityString, true, rectProvider);
         textBubble.setDismissOnTouchInteraction(true);
         View foregroundView = tileView.findViewById(org.chromium.chrome.R.id.tile_view_highlight);
-        ViewHighlighter.turnOnHighlight(foregroundView, true);
+        if (foregroundView == null) return;
+
+        PulseDrawable pulseDrawable = PulseDrawable.createCustomCircle(
+                foregroundView.getContext(), new PulseDrawable.Bounds() {
+                    @Override
+                    public float getMaxRadiusPx(Rect bounds) {
+                        return Math.min(bounds.width(), bounds.height()) / 2.f;
+                    }
+                    @Override
+                    public float getMinRadiusPx(Rect bounds) {
+                        // Radius is half of the min of width and height, divided by 1.5.
+                        // This simplifies to min of width and height divided by 3.
+                        return Math.min(bounds.width(), bounds.height()) / 3.f;
+                    }
+                });
+        ViewHighlighter.attachViewAsHighlight(foregroundView, pulseDrawable);
+
         textBubble.addOnDismissListener(() -> {
             ViewHighlighter.turnOffHighlight(foregroundView);
 

chrome/android/java/src/org/chromium/chrome/browser/widget/PulseDrawable.java

@@ -61,6 +61,45 @@ public class PulseDrawable extends Drawable implements Animatable {
         void draw(PulseDrawable drawable, Paint paint, Canvas canvas, float interpolation);
     }
 
+    /**
+     * Interface for calculating the max and min bounds in a pulsing circle.
+     */
+    public interface Bounds {
+        /**
+         * Calculates the maximum radius of a pulsing circle.
+         * @param bounds the bounds of the canvas.
+         * @return floating point maximum radius.
+         */
+        float getMaxRadiusPx(Rect bounds);
+
+        /**
+         * @param bounds the bounds of the canvas.
+         * @return floating point minimum radius.
+         */
+        float getMinRadiusPx(Rect bounds);
+    }
+
+    private static Painter createCirclePainter(Bounds boundsFn) {
+        return new PulseDrawable.Painter() {
+            @Override
+            public void modifyDrawable(PulseDrawable drawable, float interpolation) {
+                drawable.invalidateSelf();
+            }
+
+            @Override
+            public void draw(
+                    PulseDrawable drawable, Paint paint, Canvas canvas, float interpolation) {
+                Rect bounds = drawable.getBounds();
+
+                float minRadiusPx = boundsFn.getMinRadiusPx(bounds);
+                float maxRadiusPx = boundsFn.getMaxRadiusPx(bounds);
+                float radius = MathUtils.interpolate(minRadiusPx, maxRadiusPx, interpolation);
+
+                canvas.drawCircle(bounds.exactCenterX(), bounds.exactCenterY(), radius, paint);
+            }
+        };
+    }
+
     /**
      * Creates a {@link PulseDrawable} that will fill the bounds with a pulsing color.
      * @param context The {@link Context} under which the drawable is created.
@@ -92,25 +131,28 @@ public class PulseDrawable extends Drawable implements Animatable {
         final int startingPulseRadiusPx =
                 context.getResources().getDimensionPixelSize(R.dimen.iph_pulse_baseline_radius);
 
-        PulseDrawable.Painter painter = new PulseDrawable.Painter() {
+        return createCustomCircle(context, new Bounds() {
             @Override
-            public void modifyDrawable(PulseDrawable drawable, float interpolation) {
-                drawable.invalidateSelf();
+            public float getMaxRadiusPx(Rect bounds) {
+                return Math.min(startingPulseRadiusPx * 1.2f,
+                        Math.min(bounds.width(), bounds.height()) / 2.f);
             }
-
             @Override
-            public void draw(
-                    PulseDrawable drawable, Paint paint, Canvas canvas, float interpolation) {
-                Rect bounds = drawable.getBounds();
-                float maxAvailRadiusPx = Math.min(bounds.width(), bounds.height()) / 2.f;
-
-                float minRadiusPx = Math.min(startingPulseRadiusPx, maxAvailRadiusPx);
-                float maxRadiusPx = Math.min(startingPulseRadiusPx * 1.2f, maxAvailRadiusPx);
-                float radius = MathUtils.interpolate(minRadiusPx, maxRadiusPx, interpolation);
-
-                canvas.drawCircle(bounds.exactCenterX(), bounds.exactCenterY(), radius, paint);
+            public float getMinRadiusPx(Rect bounds) {
+                return Math.min(
+                        startingPulseRadiusPx, Math.min(bounds.width(), bounds.height()) / 2.f);
             }
-        };
+        });
+    }
+
+    /**
+     * Creates a {@link PulseDrawable} that will draw a pulsing circle as large as possible inside
+     * the bounds.
+     * @param context The {@link Context} under which the drawable is created.
+     * @return A new {@link PulseDrawable} instance.
+     */
+    public static PulseDrawable createCustomCircle(Context context, Bounds boundsfn) {
+        Painter painter = createCirclePainter(boundsfn);
 
         PulseDrawable drawable = new PulseDrawable(
                 context, PathInterpolatorCompat.create(.8f, 0.f, .6f, 1.f), painter);

chrome/android/java/src/org/chromium/chrome/browser/widget/ViewHighlighter.java

@@ -35,16 +35,28 @@ public class ViewHighlighter {
     public static void turnOnHighlight(View view, boolean circular) {
         if (view == null) return;
 
+        PulseDrawable pulseDrawable = circular ? PulseDrawable.createCircle(view.getContext())
+                                               : PulseDrawable.createHighlight(view.getContext());
+
+        attachViewAsHighlight(view, pulseDrawable);
+    }
+
+    /**
+     * Attach a custom PulseDrawable as a highlight layer over the view.
+     *
+     * Will not highlight if the view is already highlighted.
+     *
+     * @param view The view to be highlighted.
+     * @param pulseDrawable The highlight.
+     */
+    public static void attachViewAsHighlight(View view, PulseDrawable pulseDrawable) {
         boolean highlighted = view.getTag(R.id.highlight_state) != null
                 ? (boolean) view.getTag(R.id.highlight_state)
                 : false;
         if (highlighted) return;
 
-        PulseDrawable pulseDrawable = circular ? PulseDrawable.createCircle(view.getContext())
-                                               : PulseDrawable.createHighlight(view.getContext());
-
         Resources resources = view.getContext().getResources();
-        Drawable background = (Drawable) view.getBackground();
+        Drawable background = view.getBackground();
         if (background != null) {
             background = background.getConstantState().newDrawable(resources);
         }