From bac679b0d47aee0c9f3228ce2957ab4fe5b3609e Mon Sep 17 00:00:00 2001
From: Winson Chung <winsonc@google.com>
Date: Mon, 20 Oct 2014 14:11:12 -0700
Subject: [PATCH] Preloading task metadata to improve Recents startup time
 after reboot. (Bug 18057321)

Change-Id: I7fc627c79fe369e444ab411d109c439f796d67ff
---
 .../recents/AlternateRecentsComponent.java    |  3 +++
 .../systemui/recents/RecentsActivity.java     | 21 ++++++++++++++-----
 .../recents/model/RecentsTaskLoader.java      | 16 ++++++++++++--
 3 files changed, 33 insertions(+), 7 deletions(-)

diff --git a/packages/SystemUI/src/com/android/systemui/recents/AlternateRecentsComponent.java b/packages/SystemUI/src/com/android/systemui/recents/AlternateRecentsComponent.java
index d66add5c63228..1d748fadc3fa2 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/AlternateRecentsComponent.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/AlternateRecentsComponent.java
@@ -126,6 +126,9 @@ public class AlternateRecentsComponent {
                 }
             }
         }
+
+        // When we start, preload the metadata associated with the previous tasks
+        RecentsTaskLoader.getInstance().preload(mContext);
     }
 
     public void onBootCompleted() {
diff --git a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
index 2b55c1f27f110..d2c55f71ca467 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/RecentsActivity.java
@@ -28,6 +28,8 @@ import android.content.Intent;
 import android.content.IntentFilter;
 import android.content.SharedPreferences;
 import android.os.Bundle;
+import android.os.Handler;
+import android.os.Looper;
 import android.os.UserHandle;
 import android.util.Pair;
 import android.view.KeyEvent;
@@ -102,8 +104,7 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
         @Override
         public void run() {
             // Mark Recents as no longer visible
-            AlternateRecentsComponent.notifyVisibilityChanged(false);
-            mVisible = false;
+            onRecentsActivityVisibilityChanged(false);
             // Finish Recents
             if (mLaunchIntent != null) {
                 if (mLaunchOpts != null) {
@@ -155,6 +156,8 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
             if (action.equals(Intent.ACTION_SCREEN_OFF)) {
                 // When the screen turns off, dismiss Recents to Home
                 dismissRecentsToHome(false);
+                // Start preloading some tasks in the background
+                RecentsTaskLoader.getInstance().preload(RecentsActivity.this);
             } else if (action.equals(SearchManager.INTENT_GLOBAL_SEARCH_ACTIVITY_CHANGED)) {
                 // When the search activity changes, update the Search widget
                 refreshSearchWidget();
@@ -425,6 +428,7 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
         }
     }
 
+    /** Called when the configuration changes. */
     void onConfigurationChange() {
         // Update RecentsConfiguration
         mConfig = RecentsConfiguration.reinitialize(this,
@@ -437,6 +441,14 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
         mScrimViews.startEnterRecentsAnimation();
     }
 
+    /** Handles changes to the activity visibility. */
+    void onRecentsActivityVisibilityChanged(boolean visible) {
+        if (!visible) {
+            AlternateRecentsComponent.notifyVisibilityChanged(visible);
+        }
+        mVisible = visible;
+    }
+
     @Override
     protected void onNewIntent(Intent intent) {
         super.onNewIntent(intent);
@@ -473,7 +485,7 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
         super.onResume();
 
         // Mark Recents as visible
-        mVisible = true;
+        onRecentsActivityVisibilityChanged(true);
     }
 
     @Override
@@ -605,8 +617,7 @@ public class RecentsActivity extends Activity implements RecentsView.RecentsView
     @Override
     public void onTaskViewClicked() {
         // Mark recents as no longer visible
-        AlternateRecentsComponent.notifyVisibilityChanged(false);
-        mVisible = false;
+        onRecentsActivityVisibilityChanged(false);
     }
 
     @Override
diff --git a/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoader.java b/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoader.java
index 114e93f329d91..594eb0e43c125 100644
--- a/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoader.java
+++ b/packages/SystemUI/src/com/android/systemui/recents/model/RecentsTaskLoader.java
@@ -418,13 +418,25 @@ public class RecentsTaskLoader {
         root.setStack(stack);
 
         // Start the task loader and add all the tasks we need to load
-        mLoader.start(context);
         mLoadQueue.addTasks(tasksToLoad);
+        mLoader.start(context);
+
         return root;
     }
 
+    /** Preloads the set of recent tasks (not including thumbnails). */
+    public void preload(Context context) {
+        ArrayList<Task> tasksToLoad = new ArrayList<Task>();
+        getTaskStack(mSystemServicesProxy, context.getResources(),
+                -1, -1, true, true, null, tasksToLoad);
+
+        // Start the task loader and add all the tasks we need to load
+        mLoadQueue.addTasks(tasksToLoad);
+        mLoader.start(context);
+    }
+
     /** Creates a lightweight stack of the current recent tasks, without thumbnails and icons. */
-    public TaskStack getTaskStack(SystemServicesProxy ssp, Resources res,
+    public synchronized TaskStack getTaskStack(SystemServicesProxy ssp, Resources res,
             int preloadTaskId, int preloadTaskCount,
             boolean loadTaskThumbnails, boolean isTopTaskHome,
             List<Task.TaskKey> taskKeysOut, List<Task> tasksToLoadOut) {