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