Introduce Queue-Based Notification Snackbars

chrome/android/java/src/org/chromium/chrome/browser/snackbar/SnackbarPopupWindow.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.snackbar;
 
 import android.graphics.Bitmap;
 import android.graphics.drawable.GradientDrawable;
 import android.view.LayoutInflater;
 import android.view.View;
 import android.view.View.OnClickListener;
 import android.view.ViewGroup;
 import android.widget.ImageView;
 import android.widget.PopupWindow;
 import android.widget.TextView;
 
 import org.chromium.base.ApiCompatibilityUtils;
 import org.chromium.chrome.R;
 import org.chromium.ui.base.DeviceFormFactor;
 
 /**
  * Visual representation of a snackbar. On phone it fills the width of the activity; on tablet it
  * has a fixed width and is anchored at the start-bottom corner of the current window.
  */
 class SnackbarPopupWindow extends PopupWindow {
     private final TemplatePreservingTextView mMessageView;
     private final TextView mActionButtonView;
     private final ImageView mProfileImageView;
     private final int mAnimationDuration;
+    private Snackbar mSnackbar;
 
     /**
      * Creates an instance of the {@link SnackbarPopupWindow}.
      * @param parent Parent View the popup window anchors to
      * @param listener An {@link OnClickListener} that will be called when the action button is
      *                 clicked.
      * @param snackbar The snackbar to be displayed.
      */
     SnackbarPopupWindow(View parent, OnClickListener listener, Snackbar snackbar) {
         View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.snackbar, null);
@@ skipping 14 matching lines @@
         setHeight(ViewGroup.LayoutParams.WRAP_CONTENT);
         update(snackbar, false);
     }
 
     @Override
     public void dismiss() {
         // Disable action button during animation.
         mActionButtonView.setEnabled(false);
         super.dismiss();
     }
+    /**

[newt (away), 2016/01/27 02:13:41]

newline before this

[Ian Wen, 2016/01/27 18:14:07]

Done.

+     * Updates the view to display data from the given snackbar. No-op if the popup is already
+     * showing the given snackbar.
+     * @param snackbar The snackbar to display
+     * @return Whether update has actually been executed.
+     */
+    boolean update(Snackbar snackbar) {
+        return update(snackbar, true);
+    }
 
-    /**
-     * Updates the view to display data from the given snackbar.
-     *
-     * @param snackbar The snackbar to display
-     * @param animate Whether or not to animate the text in or set it immediately
-     */
-    void update(Snackbar snackbar, boolean animate) {
+    private boolean update(Snackbar snackbar, boolean animate) {
+        if (mSnackbar == snackbar) return false;
+        mSnackbar = snackbar;
         mMessageView.setMaxLines(snackbar.getSingleLine() ? 1 : Integer.MAX_VALUE);
         mMessageView.setTemplate(snackbar.getTemplateText());
         setViewText(mMessageView, snackbar.getText(), animate);
         String actionText = snackbar.getActionText();
 
         View view = getContentView();
         int backgroundColor = snackbar.getBackgroundColor();
         if (backgroundColor == 0) {
             backgroundColor = ApiCompatibilityUtils.getColor(view.getResources(),
                     R.color.snackbar_background_color);
@@ skipping 15 matching lines @@
             setViewText(mActionButtonView, snackbar.getActionText(), animate);
         } else {
             mActionButtonView.setVisibility(View.GONE);
         }
         Bitmap profileImage = snackbar.getProfileImage();
         if (profileImage != null) {
             mProfileImageView.setImageBitmap(profileImage);
         } else {
             ((ViewGroup) view).removeView(mProfileImageView);
         }
+        return true;
     }
 
     private void setViewText(TextView view, CharSequence text, boolean animate) {
         if (view.getText().toString().equals(text)) return;
         view.animate().cancel();
         if (animate) {
             view.setAlpha(0.0f);
             view.setText(text);
             view.animate().alpha(1.f).setDuration(mAnimationDuration).setListener(null);
         } else {
             view.setText(text);
         }
     }
 
     /**
      * Sends an accessibility event to mMessageView announcing that this window was added so that
      * the mMessageView content description is read aloud if accessibility is enabled.
      */
     void announceforAccessibility() {
         mMessageView.announceForAccessibility(mMessageView.getContentDescription());
     }
 }