RecentApplicationsDialog.java revision 621e17de87f18003aba2dedb719a2941020a7902 
1/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package com.android.internal.policy.impl;
18
19import android.app.ActivityManager;
20import android.app.ActivityManagerNative;
21import android.app.Dialog;
22import android.app.IActivityManager;
23import android.app.StatusBarManager;
24import android.content.ActivityNotFoundException;
25import android.content.BroadcastReceiver;
26import android.content.Context;
27import android.content.Intent;
28import android.content.IntentFilter;
29import android.content.res.Resources;
30import android.content.pm.ActivityInfo;
31import android.content.pm.PackageManager;
32import android.content.pm.ResolveInfo;
33import android.graphics.drawable.Drawable;
34import android.os.Bundle;
35import android.os.Handler;
36import android.os.RemoteException;
37import android.util.Log;
38import android.view.View;
39import android.view.Window;
40import android.view.WindowManager;
41import android.view.View.OnClickListener;
42import android.widget.TextView;
43
44import java.util.List;
45
46public class RecentApplicationsDialog extends Dialog implements OnClickListener {
47    // Elements for debugging support
48//  private static final String LOG_TAG = "RecentApplicationsDialog";
49    private static final boolean DBG_FORCE_EMPTY_LIST = false;
50
51    static private StatusBarManager sStatusBar;
52
53    private static final int NUM_BUTTONS = 8;
54    private static final int MAX_RECENT_TASKS = NUM_BUTTONS * 2;    // allow for some discards
55
56    final TextView[] mIcons = new TextView[NUM_BUTTONS];
57    View mNoAppsText;
58    IntentFilter mBroadcastIntentFilter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
59
60    class RecentTag {
61        ActivityManager.RecentTaskInfo info;
62        Intent intent;
63    }
64
65    Handler mHandler = new Handler();
66    Runnable mCleanup = new Runnable() {
67        public void run() {
68            // dump extra memory we're hanging on to
69            for (TextView icon: mIcons) {
70                icon.setCompoundDrawables(null, null, null, null);
71                icon.setTag(null);
72            }
73        }
74    };
75
76    private int mIconSize;
77
78    public RecentApplicationsDialog(Context context) {
79        super(context, com.android.internal.R.style.Theme_Dialog_RecentApplications);
80
81        final Resources resources = context.getResources();
82        mIconSize = (int) resources.getDimension(android.R.dimen.app_icon_size);
83    }
84
85    /**
86     * We create the recent applications dialog just once, and it stays around (hidden)
87     * until activated by the user.
88     *
89     * @see PhoneWindowManager#showRecentAppsDialog
90     */
91    @Override
92    protected void onCreate(Bundle savedInstanceState) {
93        super.onCreate(savedInstanceState);
94
95        Context context = getContext();
96
97        if (sStatusBar == null) {
98            sStatusBar = (StatusBarManager)context.getSystemService(Context.STATUS_BAR_SERVICE);
99        }
100
101        Window window = getWindow();
102        window.requestFeature(Window.FEATURE_NO_TITLE);
103        window.setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
104        window.setFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM,
105                WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM);
106        window.setTitle("Recents");
107
108        setContentView(com.android.internal.R.layout.recent_apps_dialog);
109
110        final WindowManager.LayoutParams params = window.getAttributes();
111        params.width = WindowManager.LayoutParams.MATCH_PARENT;
112        params.height = WindowManager.LayoutParams.MATCH_PARENT;
113        window.setAttributes(params);
114        window.setFlags(0, WindowManager.LayoutParams.FLAG_DIM_BEHIND);
115
116        mIcons[0] = (TextView)findViewById(com.android.internal.R.id.button0);
117        mIcons[1] = (TextView)findViewById(com.android.internal.R.id.button1);
118        mIcons[2] = (TextView)findViewById(com.android.internal.R.id.button2);
119        mIcons[3] = (TextView)findViewById(com.android.internal.R.id.button3);
120        mIcons[4] = (TextView)findViewById(com.android.internal.R.id.button4);
121        mIcons[5] = (TextView)findViewById(com.android.internal.R.id.button5);
122        mIcons[6] = (TextView)findViewById(com.android.internal.R.id.button6);
123        mIcons[7] = (TextView)findViewById(com.android.internal.R.id.button7);
124        mNoAppsText = findViewById(com.android.internal.R.id.no_applications_message);
125
126        for (TextView b: mIcons) {
127            b.setOnClickListener(this);
128        }
129    }
130
131    /**
132     * Handler for user clicks.  If a button was clicked, launch the corresponding activity.
133     */
134    public void onClick(View v) {
135
136        for (TextView b: mIcons) {
137            if (b == v) {
138                RecentTag tag = (RecentTag)b.getTag();
139                if (tag.info.id >= 0) {
140                    // This is an active task; it should just go to the foreground.
141                    final ActivityManager am = (ActivityManager)
142                            getContext().getSystemService(Context.ACTIVITY_SERVICE);
143                    am.moveTaskToFront(tag.info.id, ActivityManager.MOVE_TASK_WITH_HOME);
144                } else if (tag.intent != null) {
145                    tag.intent.addFlags(Intent.FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY
146                            | Intent.FLAG_ACTIVITY_TASK_ON_HOME);
147                    try {
148                        getContext().startActivity(tag.intent);
149                    } catch (ActivityNotFoundException e) {
150                        Log.w("Recent", "Unable to launch recent task", e);
151                    }
152                }
153                break;
154            }
155        }
156        dismiss();
157    }
158
159    /**
160     * Set up and show the recent activities dialog.
161     */
162    @Override
163    public void onStart() {
164        super.onStart();
165        reloadButtons();
166        if (sStatusBar != null) {
167            sStatusBar.disable(StatusBarManager.DISABLE_EXPAND);
168        }
169
170        // receive broadcasts
171        getContext().registerReceiver(mBroadcastReceiver, mBroadcastIntentFilter);
172
173        mHandler.removeCallbacks(mCleanup);
174    }
175
176    /**
177     * Dismiss the recent activities dialog.
178     */
179    @Override
180    public void onStop() {
181        super.onStop();
182
183        if (sStatusBar != null) {
184            sStatusBar.disable(StatusBarManager.DISABLE_NONE);
185        }
186
187        // stop receiving broadcasts
188        getContext().unregisterReceiver(mBroadcastReceiver);
189
190        mHandler.postDelayed(mCleanup, 100);
191     }
192
193    /**
194     * Reload the 6 buttons with recent activities
195     */
196    private void reloadButtons() {
197
198        final Context context = getContext();
199        final PackageManager pm = context.getPackageManager();
200        final ActivityManager am = (ActivityManager)
201                context.getSystemService(Context.ACTIVITY_SERVICE);
202        final List<ActivityManager.RecentTaskInfo> recentTasks =
203                am.getRecentTasks(MAX_RECENT_TASKS, ActivityManager.RECENT_IGNORE_UNAVAILABLE);
204
205        ActivityInfo homeInfo =
206            new Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
207                    .resolveActivityInfo(pm, 0);
208
209        IconUtilities iconUtilities = new IconUtilities(getContext());
210
211        // Performance note:  Our android performance guide says to prefer Iterator when
212        // using a List class, but because we know that getRecentTasks() always returns
213        // an ArrayList<>, we'll use a simple index instead.
214        int index = 0;
215        int numTasks = recentTasks.size();
216        for (int i = 0; i < numTasks && (index < NUM_BUTTONS); ++i) {
217            final ActivityManager.RecentTaskInfo info = recentTasks.get(i);
218
219            // for debug purposes only, disallow first result to create empty lists
220            if (DBG_FORCE_EMPTY_LIST && (i == 0)) continue;
221
222            Intent intent = new Intent(info.baseIntent);
223            if (info.origActivity != null) {
224                intent.setComponent(info.origActivity);
225            }
226
227            // Skip the current home activity.
228            if (homeInfo != null) {
229                if (homeInfo.packageName.equals(
230                        intent.getComponent().getPackageName())
231                        && homeInfo.name.equals(
232                                intent.getComponent().getClassName())) {
233                    continue;
234                }
235            }
236
237            intent.setFlags((intent.getFlags()&~Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED)
238                    | Intent.FLAG_ACTIVITY_NEW_TASK);
239            final ResolveInfo resolveInfo = pm.resolveActivity(intent, 0);
240            if (resolveInfo != null) {
241                final ActivityInfo activityInfo = resolveInfo.activityInfo;
242                final String title = activityInfo.loadLabel(pm).toString();
243                Drawable icon = activityInfo.loadIcon(pm);
244
245                if (title != null && title.length() > 0 && icon != null) {
246                    final TextView tv = mIcons[index];
247                    tv.setText(title);
248                    icon = iconUtilities.createIconDrawable(icon);
249                    tv.setCompoundDrawables(null, icon, null, null);
250                    RecentTag tag = new RecentTag();
251                    tag.info = info;
252                    tag.intent = intent;
253                    tv.setTag(tag);
254                    tv.setVisibility(View.VISIBLE);
255                    tv.setPressed(false);
256                    tv.clearFocus();
257                    ++index;
258                }
259            }
260        }
261
262        // handle the case of "no icons to show"
263        mNoAppsText.setVisibility((index == 0) ? View.VISIBLE : View.GONE);
264
265        // hide the rest
266        for (; index < NUM_BUTTONS; ++index) {
267            mIcons[index].setVisibility(View.GONE);
268        }
269    }
270
271    /**
272     * This is the listener for the ACTION_CLOSE_SYSTEM_DIALOGS intent.  It's an indication that
273     * we should close ourselves immediately, in order to allow a higher-priority UI to take over
274     * (e.g. phone call received).
275     */
276    private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
277        @Override
278        public void onReceive(Context context, Intent intent) {
279            String action = intent.getAction();
280            if (Intent.ACTION_CLOSE_SYSTEM_DIALOGS.equals(action)) {
281                String reason = intent.getStringExtra(PhoneWindowManager.SYSTEM_DIALOG_REASON_KEY);
282                if (! PhoneWindowManager.SYSTEM_DIALOG_REASON_RECENT_APPS.equals(reason)) {
283                    dismiss();
284                }
285            }
286        }
287    };
288}
289