Enable Tracing on content shell for Android

content/shell/android/java/src/org/chromium/content_shell/ContentShellActivity.java

 // Copyright (c) 2012 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.content_shell;
 
 import android.app.Activity;
+import android.content.BroadcastReceiver;
+import android.content.Context;
 import android.content.Intent;
+import android.content.IntentFilter;
 import android.os.Bundle;
 import android.text.TextUtils;
 import android.util.Log;
 import android.view.KeyEvent;
 
 import org.chromium.base.ChromiumActivity;
 import org.chromium.content.app.LibraryLoader;
 import org.chromium.content.browser.ActivityContentVideoViewDelegate;
 import org.chromium.content.browser.ContentVideoView;
 import org.chromium.content.browser.ContentView;
 import org.chromium.content.browser.DeviceUtils;
 import org.chromium.content.common.CommandLine;
 import org.chromium.ui.gfx.ActivityNativeWindow;
 
 /**
  * Activity for managing the Content Shell.
  */
 public class ContentShellActivity extends ChromiumActivity {
 
     public static final String COMMAND_LINE_FILE = "/data/local/tmp/content-shell-command-line";
     private static final String TAG = ContentShellActivity.class.getName();
 
     private static final String ACTIVE_SHELL_URL_KEY = "activeUrl";
+    private static final String ACTION_START_TRACE = "com.contentshell.action.PROFILE_START";

[Ted C, 2012/12/26 16:18:28]

This should probably be:

org.chromium.content_shell.action.PROFILE_START (don't know if the action is
required at all)

+    private static final String ACTION_STOP_TRACE = "com.contentshell.action.PROFILE_STOP";
     public static final String DEFAULT_SHELL_URL = "http://www.google.com";
     public static final String COMMAND_LINE_ARGS_KEY = "commandLineArgs";
 
     private ShellManager mShellManager;
     private ActivityNativeWindow mActivityNativeWindow;
+    private BroadcastReceiver mReceiver;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
 
         // Initializing the command line must occur before loading the library.
         if (!CommandLine.isInitialized()) {
             CommandLine.initFromFile(COMMAND_LINE_FILE);
             String[] commandLineParams = getCommandLineParamsFromIntent(getIntent());
             if (commandLineParams != null) {
@@ skipping 75 matching lines @@
             }
         }
     }
 
     @Override
     protected void onPause() {
         ContentView view = getActiveContentView();
         if (view != null) view.onActivityPause();
 
         super.onPause();
+        unregisterReceiver(mReceiver);
     }
 
     @Override
     protected void onResume() {
         super.onResume();
 
         ContentView view = getActiveContentView();
         if (view != null) view.onActivityResume();
+        IntentFilter intentFilter = new IntentFilter(ACTION_START_TRACE);
+        intentFilter.addAction(ACTION_STOP_TRACE);
+        mReceiver = new BroadcastReceiver() {
+            @Override
+            public void onReceive(Context context, Intent intent) {
+                String action = intent.getAction();
+                String extra = intent.getStringExtra("file");
+                if (action.equals(ACTION_START_TRACE) && (extra.length() > 0)) {

[Ted C, 2012/12/26 16:18:28]

When comparing against constants, I prefer to use the non-NPE-able format of:

ACTION_START_TRACE.equals(action)

Also, I would move the extraction of the file into this conditional as you
should probably print an error if people are passing this intent without a file
parameter.

Also, I would use TextUtils.isEmpty(extra) instead of explicitly checking the
length.

+                    Log.i("ContentShell", "start tracing");
+                    TraceController.beginTracing(extra);
+                } else if (action.equals(ACTION_STOP_TRACE)) {
+                    Log.i("ContentShell", "stop tracing");
+                    TraceController.endTracing();
+                }
+            }
+        };
+        registerReceiver(mReceiver, intentFilter);
     }
 
+

[Ted C, 2012/12/26 16:18:28]

no need for this extra line

     @Override
     public void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);
         mActivityNativeWindow.onActivityResult(requestCode, resultCode, data);
     }
 
     private static String getUrlFromIntent(Intent intent) {
         return intent != null ? intent.getDataString() : null;
     }
 
@@ skipping 18 matching lines @@
 
     /**
      * @return The {@link ContentView} owned by the currently visible {@link Shell} or null if one
      *         is not showing.
      */
     public ContentView getActiveContentView() {
         Shell shell = getActiveShell();
         return shell != null ? shell.getContentView() : null;
     }
 }