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 204 matching lines @@
     public void init(View root, View controlContainer) {
         mToolbarHeight = controlContainer.getHeight();
         mCurrentState = 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) {
                 mContainerHeight = bottom - top;
                 updateSheetPeekHeight(mToolbarHeight, mContainerHeight);
-                setSheetState(mCurrentState, false);
+
+                // If animating, don't reset the sheet position.
+                if (!isRunningSettleAnimation()) setSheetState(mCurrentState, false);

[Ian Wen, 2017/01/17 19:23:59]

I think you could cancel the current animation, and then call setSheetState().

If you simply check if animation is running, I bet you will encounter some edge
case where after an orientation change the sheet is in wrong state or so.

[mdjones, 2017/01/17 21:59:31]

This was for when the keyboard shows, onLayoutChange is called without the
dimensions actually changing. I have updated the code to reflect this and
address your comment.

             }
         });
 
         // 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) {
                 mToolbarHeight = bottom - top;
                 updateSheetPeekHeight(mToolbarHeight, mContainerHeight);
-                setSheetState(mCurrentState, false);
+
+                // If animating, don't reset the sheet position.
+                if (!isRunningSettleAnimation()) setSheetState(mCurrentState, false);
             }
         });
     }
 
     /**
      * Get the unadjusted version of a MotionEvent.
      * @param e The original event.
      * @return The unadjusted version of the event.
      */
     private MotionEvent getRawMotionEvent(MotionEvent e) {
@@ skipping 87 matching lines @@
     private void setSheetOffsetFromBottom(float offset) {
         setTranslationY(mContainerHeight - offset);
     }
 
     /**
      * Move 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(int state, boolean animate) {
+    public void setSheetState(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;
+    }
+
+    /**
      * Get 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(int state) {
         return mStateRatios[state] * mContainerHeight;
     }
 
     /**
      * Get 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;
         }
     }
 }