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.Dialog;
21import android.app.StatusBarManager;
22import android.content.BroadcastReceiver;
23import android.content.ComponentName;
24import android.content.Context;
25import android.content.Intent;
26import android.content.IntentFilter;
27import android.content.res.Resources;
28import android.content.pm.ActivityInfo;
29import android.content.pm.PackageManager;
30import android.content.pm.ResolveInfo;
31import android.graphics.drawable.Drawable;
32import android.os.Bundle;
33import android.os.Handler;
34import android.os.Message;
35import android.view.View;
36import android.view.Window;
37import android.view.WindowManager;
38import android.view.View.OnClickListener;
39import android.widget.ImageView;
40import android.widget.TextView;
41
42import java.util.List;
43
44public class RecentApplicationsDialog extends Dialog implements OnClickListener {
45    // Elements for debugging support
46//  private static final String LOG_TAG = "RecentApplicationsDialog";
47    private static final boolean DBG_FORCE_EMPTY_LIST = false;
48
49    static private StatusBarManager sStatusBar;
50
51    private static final int NUM_BUTTONS = 6;
52    private static final int MAX_RECENT_TASKS = NUM_BUTTONS * 2;    // allow for some discards
53
54    final View[] mButtons = new View[NUM_BUTTONS];
55    View mNoAppsText;
56    IntentFilter mBroadcastIntentFilter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
57
58
59    private int mIconSize;
60
61    public RecentApplicationsDialog(Context context) {
62        super(context);
63
64        final Resources resources = context.getResources();
65        mIconSize = (int) resources.getDimension(android.R.dimen.app_icon_size);
66    }
67
68    /**
69     * We create the recent applications dialog just once, and it stays around (hidden)
70     * until activated by the user.
71     *
72     * @see PhoneWindowManager#showRecentAppsDialog
73     */
74    @Override
75    protected void onCreate(Bundle savedInstanceState) {
76        super.onCreate(savedInstanceState);
77
78        Context context = getContext();
79
80        if (sStatusBar == null) {
81            sStatusBar = (StatusBarManager)context.getSystemService(Context.STATUS_BAR_SERVICE);
82        }
83
84        Window theWindow = getWindow();
85        theWindow.requestFeature(Window.FEATURE_NO_TITLE);
86        theWindow.setType(WindowManager.LayoutParams.TYPE_SYSTEM_DIALOG);
87        theWindow.setFlags(WindowManager.LayoutParams.FLAG_BLUR_BEHIND,
88                WindowManager.LayoutParams.FLAG_BLUR_BEHIND);
89        theWindow.setFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM,
90                WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM);
91        theWindow.setTitle("Recents");
92
93        setContentView(com.android.internal.R.layout.recent_apps_dialog);
94
95        mButtons[0] = findViewById(com.android.internal.R.id.button1);
96        mButtons[1] = findViewById(com.android.internal.R.id.button2);
97        mButtons[2] = findViewById(com.android.internal.R.id.button3);
98        mButtons[3] = findViewById(com.android.internal.R.id.button4);
99        mButtons[4] = findViewById(com.android.internal.R.id.button5);
100        mButtons[5] = findViewById(com.android.internal.R.id.button6);
101        mNoAppsText = findViewById(com.android.internal.R.id.no_applications_message);
102
103        for (View b : mButtons) {
104            b.setOnClickListener(this);
105        }
106    }
107
108    /**
109     * Handler for user clicks.  If a button was clicked, launch the corresponding activity.
110     */
111    public void onClick(View v) {
112
113        for (View b : mButtons) {
114            if (b == v) {
115                // prepare a launch intent and send it
116                Intent intent = (Intent)b.getTag();
117                intent.addFlags(Intent.FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY);
118                getContext().startActivity(intent);
119            }
120        }
121        dismiss();
122    }
123
124    /**
125     * Set up and show the recent activities dialog.
126     */
127    @Override
128    public void onStart() {
129        super.onStart();
130        reloadButtons();
131        if (sStatusBar != null) {
132            sStatusBar.disable(StatusBarManager.DISABLE_EXPAND);
133        }
134
135        // receive broadcasts
136        getContext().registerReceiver(mBroadcastReceiver, mBroadcastIntentFilter);
137    }
138
139    /**
140     * Dismiss the recent activities dialog.
141     */
142    @Override
143    public void onStop() {
144        super.onStop();
145
146        // dump extra memory we're hanging on to
147        for (View b : mButtons) {
148            setButtonAppearance(b, null, null);
149            b.setTag(null);
150        }
151
152        if (sStatusBar != null) {
153            sStatusBar.disable(StatusBarManager.DISABLE_NONE);
154        }
155
156        // stop receiving broadcasts
157        getContext().unregisterReceiver(mBroadcastReceiver);
158     }
159
160    /**
161     * Reload the 6 buttons with recent activities
162     */
163    private void reloadButtons() {
164
165        final Context context = getContext();
166        final PackageManager pm = context.getPackageManager();
167        final ActivityManager am = (ActivityManager)
168                                        context.getSystemService(Context.ACTIVITY_SERVICE);
169        final List<ActivityManager.RecentTaskInfo> recentTasks =
170                                        am.getRecentTasks(MAX_RECENT_TASKS, 0);
171
172        ResolveInfo homeInfo = pm.resolveActivity(
173                new Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME),
174                0);
175
176        // Performance note:  Our android performance guide says to prefer Iterator when
177        // using a List class, but because we know that getRecentTasks() always returns
178        // an ArrayList<>, we'll use a simple index instead.
179        int button = 0;
180        int numTasks = recentTasks.size();
181        for (int i = 0; i < numTasks && (button < NUM_BUTTONS); ++i) {
182            final ActivityManager.RecentTaskInfo info = recentTasks.get(i);
183
184            // for debug purposes only, disallow first result to create empty lists
185            if (DBG_FORCE_EMPTY_LIST && (i == 0)) continue;
186
187            Intent intent = new Intent(info.baseIntent);
188            if (info.origActivity != null) {
189                intent.setComponent(info.origActivity);
190            }
191
192            // Skip the current home activity.
193            if (homeInfo != null) {
194                if (homeInfo.activityInfo.packageName.equals(
195                        intent.getComponent().getPackageName())
196                        && homeInfo.activityInfo.name.equals(
197                                intent.getComponent().getClassName())) {
198                    continue;
199                }
200            }
201
202            intent.setFlags((intent.getFlags()&~Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED)
203                    | Intent.FLAG_ACTIVITY_NEW_TASK);
204            final ResolveInfo resolveInfo = pm.resolveActivity(intent, 0);
205            if (resolveInfo != null) {
206                final ActivityInfo activityInfo = resolveInfo.activityInfo;
207                final String title = activityInfo.loadLabel(pm).toString();
208                final Drawable icon = activityInfo.loadIcon(pm);
209
210                if (title != null && title.length() > 0 && icon != null) {
211                    final View b = mButtons[button];
212                    setButtonAppearance(b, title, icon);
213                    b.setTag(intent);
214                    b.setVisibility(View.VISIBLE);
215                    b.setPressed(false);
216                    b.clearFocus();
217                    ++button;
218                }
219            }
220        }
221
222        // handle the case of "no icons to show"
223        mNoAppsText.setVisibility((button == 0) ? View.VISIBLE : View.GONE);
224
225        // hide the rest
226        for ( ; button < NUM_BUTTONS; ++button) {
227            mButtons[button].setVisibility(View.GONE);
228        }
229    }
230
231    /**
232     * Adjust appearance of each icon-button
233     */
234    private void setButtonAppearance(View theButton, final String theTitle, final Drawable icon) {
235        TextView tv = (TextView) theButton;
236        tv.setText(theTitle);
237        if (icon != null) {
238            icon.setBounds(0, 0, mIconSize, mIconSize);
239        }
240        tv.setCompoundDrawables(null, icon, null, null);
241    }
242
243    /**
244     * This is the listener for the ACTION_CLOSE_SYSTEM_DIALOGS intent.  It's an indication that
245     * we should close ourselves immediately, in order to allow a higher-priority UI to take over
246     * (e.g. phone call received).
247     */
248    private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
249        @Override
250        public void onReceive(Context context, Intent intent) {
251            String action = intent.getAction();
252            if (Intent.ACTION_CLOSE_SYSTEM_DIALOGS.equals(action)) {
253                String reason = intent.getStringExtra(PhoneWindowManager.SYSTEM_DIALOG_REASON_KEY);
254                if (! PhoneWindowManager.SYSTEM_DIALOG_REASON_RECENT_APPS.equals(reason)) {
255                    dismiss();
256                }
257            }
258        }
259    };
260}
261