Expand bottom sheet when URL bar is focused

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

 // Copyright 2017 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.widget;
 
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.animation.ObjectAnimator;
 import android.content.Context;
@@ skipping 214 matching lines @@
      * @param controlContainer The container for the toolbar.
      */
     public void init(View root, View controlContainer) {
         mToolbarHeight = controlContainer.getHeight();
         mCurrentState = SHEET_STATE_PEEK;
 
         // Listen to height changes on the root.
         root.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
             public void onLayoutChange(View v, int left, int top, int right, int bottom,
                     int oldLeft, int oldTop, int oldRight, int oldBottom) {
+                // Make sure the size of the layout actually changed.

[gone, 2017/01/20 19:04:08]

Can't you just do equality checks?  Subtraction of two ints and comparing to
zero implies they're the same value, no?

[mdjones, 2017/01/20 20:11:47]

Yeah, not really sure what I was thinking here. Fixed.

+                if (top - oldTop == 0 && bottom - oldBottom == 0 && left - oldLeft == 0
+                        && right - oldRight == 0) {
+                    return;
+                }
+
                 mContainerHeight = bottom - top;
                 updateSheetPeekHeight();
+
+                cancelAnimation();
                 setSheetState(mCurrentState, false);
             }
         });
 
         // Listen to height changes on the toolbar.
         controlContainer.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
             public void onLayoutChange(View v, int left, int top, int right, int bottom,
                     int oldLeft, int oldTop, int oldRight, int oldBottom) {
+                // Make sure the size of the layout actually changed.
+                if (top - oldTop == 0 && bottom - oldBottom == 0 && left - oldLeft == 0
+                        && right - oldRight == 0) {
+                    return;
+                }
+
                 mToolbarHeight = bottom - top;
                 updateSheetPeekHeight();
+
+                cancelAnimation();
                 setSheetState(mCurrentState, false);
             }
         });
     }
 
     /**
      * Creates an unadjusted version of a MotionEvent.
      * @param e The original event.
      * @return The unadjusted version of the event.
      */
@@ skipping 86 matching lines @@
     private void setSheetOffsetFromBottom(float offset) {
         setTranslationY(mContainerHeight - offset);
     }
 
     /**
      * Moves the sheet to the provided state.
      * @param state The state to move the panel to.
      * @param animate If true, the sheet will animate to the provided state, otherwise it will
      *                move there instantly.
      */
-    private void setSheetState(@SheetState int state, boolean animate) {
+    public void setSheetState(@SheetState int state, boolean animate) {
         mCurrentState = state;
 
         if (animate) {
             createSettleAnimation(state);
         } else {
             setSheetOffsetFromBottom(getSheetHeightForState(state));
         }
     }
 
     /**
+     * @return The current state of the bottom sheet. If the sheet is animating, this will be the
+     *         state the sheet is animating to.
+     */
+    public int getSheetState() {
+        return mCurrentState;
+    }
+
+    /**
+     * If the animation to settle the sheet in one of its states is running.
+     * @return True if the animation is running.
+     */
+    private boolean isRunningSettleAnimation() {
+        return mSettleAnimator != null;
+    }
+
+    /**
      * Gets the height of the bottom sheet based on a provided state.
      * @param state The state to get the height from.
      * @return The height of the sheet at the provided state.
      */
     private float getSheetHeightForState(@SheetState int state) {
         return mStateRatios[state] * mContainerHeight;
     }
 
     /**
      * Gets the target state of the sheet based on the sheet's height and velocity.
@@ skipping 27 matching lines @@
         float distance = getSheetHeightForState(nextState) - lowerBound;
         float thresholdToNextState =
                 yVelocity < 0.0f ? THRESHOLD_TO_NEXT_STATE : 1.0f - THRESHOLD_TO_NEXT_STATE;
         if ((sheetHeight - lowerBound) / distance > thresholdToNextState) {
             return nextState;
         } else {
             return prevState;
         }
     }
 }