[Smart Lock] Auto sign-in snackbar UI.

chrome/android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java

Index: chrome/android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java b/chrome/android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java
new file mode 100644
index 0000000000000000000000000000000000000000..faef22544b1c81820a6e026772aca3528d8cf096
--- /dev/null
+++ b/chrome/android/java/src/org/chromium/chrome/browser/snackbar/smartlockautosignin/AutoSigninSnackbarController.java
@@ -0,0 +1,91 @@
+// 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.smartlockautosignin;
+
+import android.content.Context;
+
+import org.chromium.base.annotations.CalledByNative;
+import org.chromium.chrome.R;
+import org.chromium.chrome.browser.snackbar.Snackbar;
+import org.chromium.chrome.browser.snackbar.SnackbarManager;
+import org.chromium.chrome.browser.tab.EmptyTabObserver;
+import org.chromium.chrome.browser.tab.Tab;
+import org.chromium.chrome.browser.tab.TabObserver;
+
+/**
+ * A controller that triggers an auto sign-in snackbar. Auto sign-in snackbar is
+ * triggered on a request credentials call of a Credential Manager API.
+ */
+public class AutoSigninSnackbarController
+        implements SnackbarManager.SnackbarController {
+
+    private final SnackbarManager mSnackbarManager;
+    private final TabObserver mTabObserver;
+    private final Tab mTab;
+
+    @CalledByNative
+    private static void showSnackbar(Tab tab, String username) {
+        AutoSigninSnackbarController snackbar = new AutoSigninSnackbarController(tab);
+        snackbar.show(username);
+    }
+
+    /**
+     * Creates an instance of a {@link AutoSigninSnackbarController}.
+     * @param snackbarManager The manager that helps to show up snackbar.
+     */
+    private AutoSigninSnackbarController(Tab tab) {
+        mTab = tab;
+        mSnackbarManager = tab.getSnackbarManager();
+        mTabObserver = new EmptyTabObserver() {
+            @Override
+            public void onHidden(Tab tab) {
+                AutoSigninSnackbarController.this.dismissAutoSigninSnackbar();
+            }
+
+            @Override
+            public void onDestroyed(Tab tab) {
+                AutoSigninSnackbarController.this.dismissAutoSigninSnackbar();
+            }
+
+            @Override
+            public void onCrash(Tab tab, boolean sadTabShown) {
+                AutoSigninSnackbarController.this.dismissAutoSigninSnackbar();
+            }
+        };
+        mTab.addObserver(mTabObserver);
+    }
+
+    /**
+     * Displays Auto sign-in snackbar, which communicates to the users that they
+     * were signed in to the web site. Displays the |username| in the message.
+     */
+    private void show(String username) {
+        if (mSnackbarManager != null) {

[newt (away), 2015/08/21 16:47:32]

If mSnackbarManager, then the AutoSigninSnackbarController won't be shown, and
hence onDismissForEachType() will never be called, and the
AutoSigninSnackbarController will stick around indefinitely as a TabObserver.

I'd structure the class like this to avoid this problem:

  private static void showSnackbar(Tab tab, String username) {
      SnackbarManager snackbarManager = tab.getSnackbarManager();
      if (snackbarManager == null) return;

      AutoSigninSnackbarController controller = new
AutoSigninSnackbarController(snackbarManager, tab);
      Context context = mTab.getWindowAndroid().getApplicationContext();
      String text = context.getString(R.string.passwords_auto_signin_message);
      snackbarManager.showSnackbar(Snackbar.make(username,
controller).setTemplateText(text));
  }

[melandory, 2015/08/21 19:04:09]

Done.

+            Context context = mTab.getWindowAndroid().getApplicationContext();
+            String text = context.getString(R.string.passwords_auto_signin_message);
+            mSnackbarManager.showSnackbar(Snackbar.make(username, this).setTemplateText(text));
+        }
+    }
+
+    /**
+     * Dismisses the snackbar.
+     */
+    public void dismissAutoSigninSnackbar() {
+        if (mSnackbarManager.isShowing()) {
+            mSnackbarManager.removeMatchingSnackbars(this);
+        }
+    }
+
+    @Override
+    public void onAction(Object actionData) {}
+
+    @Override
+    public void onDismissNoAction(Object actionData) {}
+
+    @Override
+    public void onDismissForEachType(boolean isTimeout) {
+        mTab.removeObserver(mTabObserver);
+    }
+}