Peek new infobars behind existing ones

chrome/android/java/src/org/chromium/chrome/browser/infobar/InfoBarContainerLayout.java

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.chrome.browser.infobar;
 
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.AnimatorSet;
 import android.animation.ObjectAnimator;
 import android.animation.ValueAnimator;
 import android.annotation.SuppressLint;
 import android.content.Context;
 import android.content.res.Resources;
 import android.view.Gravity;
 import android.view.MotionEvent;
 import android.view.View;
 import android.widget.FrameLayout;
 
 import org.chromium.chrome.R;
 import org.chromium.chrome.browser.infobar.InfoBarContainer.InfoBarAnimationListener;
 
 import java.util.ArrayList;
+import java.util.List;
 
 /**
  * Layout that displays infobars in a stack. Handles all the animations when adding or removing
  * infobars and when swapping infobar contents.
  *
  * The first infobar to be added is visible at the front of the stack. Later infobars peek up just
  * enough behind the front infobar to signal their existence; their contents aren't visible at all.
  * The stack has a max depth of three infobars. If additional infobars are added beyond this, they
  * won't be visible at all until infobars in front of them are dismissed.
  *
@@ skipping 64 matching lines @@
     }
 
     /**
      * Creates an empty InfoBarContainerLayout.
      */
     InfoBarContainerLayout(Context context) {
         super(context);
         Resources res = context.getResources();
         mBackInfobarHeight = res.getDimensionPixelSize(R.dimen.infobar_peeking_height);
         mFloatingBehavior = new FloatingBehavior(this);
+        mBackgroundPeekSize = getResources().getDimensionPixelSize(R.dimen.min_touch_target_size);
+
+        setClipChildren(false);
     }
 
     /**
      * Adds an infobar to the container. The infobar appearing animation will happen after the
      * current animation, if any, finishes.
      */
     void addInfoBar(Item item) {
         if (item.isLegalDisclosure()) {
             mItems.add(0, item);
         } else {
@@ skipping 36 matching lines @@
 
     /////////////////////////////////////////
     // Implementation details
     /////////////////////////////////////////
 
     /** The maximum number of infobars visible at any time. */
     private static final int MAX_STACK_DEPTH = 3;
 
     // Animation durations.
     private static final int DURATION_SLIDE_UP_MS = 250;
+    private static final int DURATION_PEEK_MS = 500;
     private static final int DURATION_SLIDE_DOWN_MS = 250;
     private static final int DURATION_FADE_MS = 100;
     private static final int DURATION_FADE_OUT_MS = 200;
 
+    // The height that an infobar will peek when being added behind another one.
+    private final int mBackgroundPeekSize;
+
     /**
      * Base class for animations inside the InfoBarContainerLayout.
      *
      * Provides a standardized way to prepare for, run, and clean up after animations. Each subclass
      * should implement prepareAnimation(), createAnimator(), and onAnimationEnd() as needed.
      */
     private abstract class InfoBarAnimation {
         private Animator mAnimator;
 
         final boolean isStarted() {
@@ skipping 16 matching lines @@
             mAnimator = createAnimator();
             mAnimator.addListener(listener);
             mAnimator.start();
         }
 
         /**
          * Returns an animator that animates an InfoBarWrapper's y-translation from its current
          * value to endValue and updates the side shadow positions on each frame.
          */
         ValueAnimator createTranslationYAnimator(final InfoBarWrapper wrapper, float endValue) {
-            ValueAnimator animator = ValueAnimator.ofFloat(wrapper.getTranslationY(), endValue);
+            ValueAnimator animator = ObjectAnimator.ofFloat(wrapper, View.TRANSLATION_Y, endValue);
             animator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
                 @Override
                 public void onAnimationUpdate(ValueAnimator animation) {
-                    wrapper.setTranslationY((float) animation.getAnimatedValue());
                     mFloatingBehavior.updateShadowPosition();
                 }
             });
             return animator;
         }
 
         /**
          * Called before the animation begins. This is the time to add views to the hierarchy and
          * adjust layout parameters.
          */
@@ skipping 158 matching lines @@
 
     /**
      * The animation to show a back infobar. The infobar slides up behind the existing infobars, so
      * its top edge peeks out just a bit.
      */
     private class BackInfoBarAppearingAnimation extends InfoBarAnimation {
         private InfoBarWrapper mAppearingWrapper;
 
         BackInfoBarAppearingAnimation(Item appearingItem) {
             mAppearingWrapper = new InfoBarWrapper(getContext(), appearingItem);
+            mAppearingWrapper.addView(appearingItem.getView());
         }
 
         @Override
         void prepareAnimation() {
             addWrapper(mAppearingWrapper);
         }
 
         @Override
         Animator createAnimator() {
+            AnimatorSet set = new AnimatorSet();
+            List<Animator> animators = new ArrayList<>();
+
             mAppearingWrapper.setTranslationY(mAppearingWrapper.getHeight());
-            return createTranslationYAnimator(mAppearingWrapper, 0f)
-                    .setDuration(DURATION_SLIDE_UP_MS);
+            ValueAnimator animator =
+                    createTranslationYAnimator(mAppearingWrapper, -mBackgroundPeekSize);
+            animator.setDuration(DURATION_PEEK_MS);

[Ted C, 2017/05/17 17:55:54]

We should be able to set the duration on the set since it is the same.

Hmm...or maybe playSequentially doesn't play nicely with that

[mdjones, 2017/05/17 21:05:19]

Setting duration on the set ends up working just fine. Done.

+            animators.add(animator);
+
+            animators.add(
+                    createTranslationYAnimator(mAppearingWrapper, 0).setDuration(DURATION_PEEK_MS));
+
+            set.addListener(new AnimatorListenerAdapter() {

[Ted C, 2017/05/17 17:55:54]

Do you want the view to be removed even if the set were cancelled?  It is
probably ok in this case.

[mdjones, 2017/05/17 21:05:19]

When cancel is called on the animator set, cancel is called on each of its
constituent animations. Canceling an animation will call onAnimationEnd, so this
is run in any case.

+                @Override
+                public void onAnimationEnd(Animator animation) {
+                    mAppearingWrapper.removeView(mAppearingWrapper.getItem().getView());
+                }
+            });
+
+            set.playSequentially(animators);
+
+            return set;
         }
 
         @Override
         int getAnimationType() {
             return InfoBarAnimationListener.ANIMATION_TYPE_SHOW;
         }
     }
 
     /**
      * The animation to hide the front infobar and reveal the second-to-front infobar. The front
@@ skipping 399 matching lines @@
             LayoutParams lp = (LayoutParams) child.getLayoutParams();
             lp.topMargin = (childCount - 1 - i) * mBackInfobarHeight;
             child.setLayoutParams(lp);
         }
     }
 
     @Override
     protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
         widthMeasureSpec = mFloatingBehavior.beforeOnMeasure(widthMeasureSpec);
         super.onMeasure(widthMeasureSpec, heightMeasureSpec);
-        mFloatingBehavior.afterOnMeasure(getMeasuredHeight());
+
+        // Make sure the shadow is tall enough to compensate for the peek animation of other
+        // infboars.
+        mFloatingBehavior.afterOnMeasure(getMeasuredHeight() + mBackgroundPeekSize);
     }
 
     @Override
     protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
         super.onLayout(changed, left, top, right, bottom);
         mFloatingBehavior.updateShadowPosition();
 
         // Animations start after a layout has completed, at which point all views are guaranteed
         // to have valid sizes and positions.
         if (mAnimation != null && !mAnimation.isStarted()) {
@@ skipping 19 matching lines @@
 
     @Override
     public boolean onHoverEvent(MotionEvent event) {
         super.onHoverEvent(event);
         // Consume all hover events so they do not reach the ContentView. In touch exploration mode,
         // this prevents the user from interacting with the part of the ContentView behind the
         // infobars. http://crbug.com/430701
         return true;
     }
 }