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.ActivityNotFoundException;
23import android.content.BroadcastReceiver;
24import android.content.Context;
25import android.content.Intent;
26import android.content.IntentFilter;
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.os.Handler;
33import android.util.Log;
34import android.view.KeyEvent;
35import android.view.SoundEffectConstants;
36import android.view.View;
37import android.view.Window;
38import android.view.WindowManager;
39import android.view.View.OnClickListener;
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 = 8;
52    private static final int MAX_RECENT_TASKS = NUM_BUTTONS * 2;    // allow for some discards
53
54    final TextView[] mIcons = new TextView[NUM_BUTTONS];
55    View mNoAppsText;
56    IntentFilter mBroadcastIntentFilter = new IntentFilter(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
57
58    class RecentTag {
59        ActivityManager.RecentTaskInfo info;
60        Intent intent;
61    }
62
63    Handler mHandler = new Handler();
64    Runnable mCleanup = new Runnable() {
65        public void run() {
66            // dump extra memory we're hanging on to
67            for (TextView icon: mIcons) {
68                icon.setCompoundDrawables(null, null, null, null);
69                icon.setTag(null);
70            }
71        }
72    };
73
74    public RecentApplicationsDialog(Context context) {
75        super(context, com.android.internal.R.style.Theme_Dialog_RecentApplications);
76
77    }
78
79    /**
80     * We create the recent applications dialog just once, and it stays around (hidden)
81     * until activated by the user.
82     *
83     * @see PhoneWindowManager#showRecentAppsDialog
84     */
85    @Override
86    protected void onCreate(Bundle savedInstanceState) {
87        super.onCreate(savedInstanceState);
88
89        Context context = getContext();
90
91        if (sStatusBar == null) {
92            sStatusBar = (StatusBarManager)context.getSystemService(Context.STATUS_BAR_SERVICE);
93        }
94
95        Window window = getWindow();
96        window.requestFeature(Window.FEATURE_NO_TITLE);
97        window.setType(WindowManager.LayoutParams.TYPE_RECENTS_OVERLAY);
98        window.setFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM,
99                WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM);
100        window.setTitle("Recents");
101
102        setContentView(com.android.internal.R.layout.recent_apps_dialog);
103
104        final WindowManager.LayoutParams params = window.getAttributes();
105        params.width = WindowManager.LayoutParams.MATCH_PARENT;
106        params.height = WindowManager.LayoutParams.MATCH_PARENT;
107        window.setAttributes(params);
108        window.setFlags(0, WindowManager.LayoutParams.FLAG_DIM_BEHIND);
109
110        mIcons[0] = (TextView)findViewById(com.android.internal.R.id.button0);
111        mIcons[1] = (TextView)findViewById(com.android.internal.R.id.button1);
112        mIcons[2] = (TextView)findViewById(com.android.internal.R.id.button2);
113        mIcons[3] = (TextView)findViewById(com.android.internal.R.id.button3);
114        mIcons[4] = (TextView)findViewById(com.android.internal.R.id.button4);
115        mIcons[5] = (TextView)findViewById(com.android.internal.R.id.button5);
116        mIcons[6] = (TextView)findViewById(com.android.internal.R.id.button6);
117        mIcons[7] = (TextView)findViewById(com.android.internal.R.id.button7);
118        mNoAppsText = findViewById(com.android.internal.R.id.no_applications_message);
119
120        for (TextView b: mIcons) {
121            b.setOnClickListener(this);
122        }
123    }
124
125    @Override
126    public boolean onKeyDown(int keyCode, KeyEvent event) {
127        if (keyCode == KeyEvent.KEYCODE_TAB) {
128            // Ignore all meta keys other than SHIFT.  The app switch key could be a
129            // fallback action chorded with ALT, META or even CTRL depending on the key map.
130            // DPad navigation is handled by the ViewRoot elsewhere.
131            final boolean backward = event.isShiftPressed();
132            final int numIcons = mIcons.length;
133            int numButtons = 0;
134            while (numButtons < numIcons && mIcons[numButtons].getVisibility() == View.VISIBLE) {
135                numButtons += 1;
136            }
137            if (numButtons != 0) {
138                int nextFocus = backward ? numButtons - 1 : 0;
139                for (int i = 0; i < numButtons; i++) {
140                    if (mIcons[i].hasFocus()) {
141                        if (backward) {
142                            nextFocus = (i + numButtons - 1) % numButtons;
143                        } else {
144                            nextFocus = (i + 1) % numButtons;
145                        }
146                        break;
147                    }
148                }
149                final int direction = backward ? View.FOCUS_BACKWARD : View.FOCUS_FORWARD;
150                if (mIcons[nextFocus].requestFocus(direction)) {
151                    mIcons[nextFocus].playSoundEffect(
152                            SoundEffectConstants.getContantForFocusDirection(direction));
153                }
154            }
155
156            // The dialog always handles the key to prevent the ViewRoot from
157            // performing the default navigation itself.
158            return true;
159        }
160
161        return super.onKeyDown(keyCode, event);
162    }
163
164    /**
165     * Dismiss the dialog and switch to the selected application.
166     */
167    public void dismissAndSwitch() {
168        final int numIcons = mIcons.length;
169        RecentTag tag = null;
170        for (int i = 0; i < numIcons; i++) {
171            if (mIcons[i].getVisibility() != View.VISIBLE) {
172                break;
173            }
174            if (i == 0 || mIcons[i].hasFocus()) {
175                tag = (RecentTag) mIcons[i].getTag();
176                if (mIcons[i].hasFocus()) {
177                    break;
178                }
179            }
180        }
181        if (tag != null) {
182            switchTo(tag);
183        }
184        dismiss();
185    }
186
187    /**
188     * Handler for user clicks.  If a button was clicked, launch the corresponding activity.
189     */
190    public void onClick(View v) {
191        for (TextView b: mIcons) {
192            if (b == v) {
193                RecentTag tag = (RecentTag)b.getTag();
194                switchTo(tag);
195                break;
196            }
197        }
198        dismiss();
199    }
200
201    private void switchTo(RecentTag tag) {
202        if (tag.info.id >= 0) {
203            // This is an active task; it should just go to the foreground.
204            final ActivityManager am = (ActivityManager)
205                    getContext().getSystemService(Context.ACTIVITY_SERVICE);
206            am.moveTaskToFront(tag.info.id, ActivityManager.MOVE_TASK_WITH_HOME);
207        } else if (tag.intent != null) {
208            tag.intent.addFlags(Intent.FLAG_ACTIVITY_LAUNCHED_FROM_HISTORY
209                    | Intent.FLAG_ACTIVITY_TASK_ON_HOME);
210            try {
211                getContext().startActivity(tag.intent);
212            } catch (ActivityNotFoundException e) {
213                Log.w("Recent", "Unable to launch recent task", e);
214            }
215        }
216    }
217
218    /**
219     * Set up and show the recent activities dialog.
220     */
221    @Override
222    public void onStart() {
223        super.onStart();
224        reloadButtons();
225        if (sStatusBar != null) {
226            sStatusBar.disable(StatusBarManager.DISABLE_EXPAND);
227        }
228
229        // receive broadcasts
230        getContext().registerReceiver(mBroadcastReceiver, mBroadcastIntentFilter);
231
232        mHandler.removeCallbacks(mCleanup);
233    }
234
235    /**
236     * Dismiss the recent activities dialog.
237     */
238    @Override
239    public void onStop() {
240        super.onStop();
241
242        if (sStatusBar != null) {
243            sStatusBar.disable(StatusBarManager.DISABLE_NONE);
244        }
245
246        // stop receiving broadcasts
247        getContext().unregisterReceiver(mBroadcastReceiver);
248
249        mHandler.postDelayed(mCleanup, 100);
250     }
251
252    /**
253     * Reload the 6 buttons with recent activities
254     */
255    private void reloadButtons() {
256
257        final Context context = getContext();
258        final PackageManager pm = context.getPackageManager();
259        final ActivityManager am = (ActivityManager)
260                context.getSystemService(Context.ACTIVITY_SERVICE);
261        final List<ActivityManager.RecentTaskInfo> recentTasks =
262                am.getRecentTasks(MAX_RECENT_TASKS, ActivityManager.RECENT_IGNORE_UNAVAILABLE);
263
264        ActivityInfo homeInfo =
265            new Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
266                    .resolveActivityInfo(pm, 0);
267
268        IconUtilities iconUtilities = new IconUtilities(getContext());
269
270        // Performance note:  Our android performance guide says to prefer Iterator when
271        // using a List class, but because we know that getRecentTasks() always returns
272        // an ArrayList<>, we'll use a simple index instead.
273        int index = 0;
274        int numTasks = recentTasks.size();
275        for (int i = 0; i < numTasks && (index < NUM_BUTTONS); ++i) {
276            final ActivityManager.RecentTaskInfo info = recentTasks.get(i);
277
278            // for debug purposes only, disallow first result to create empty lists
279            if (DBG_FORCE_EMPTY_LIST && (i == 0)) continue;
280
281            Intent intent = new Intent(info.baseIntent);
282            if (info.origActivity != null) {
283                intent.setComponent(info.origActivity);
284            }
285
286            // Skip the current home activity.
287            if (homeInfo != null) {
288                if (homeInfo.packageName.equals(
289                        intent.getComponent().getPackageName())
290                        && homeInfo.name.equals(
291                                intent.getComponent().getClassName())) {
292                    continue;
293                }
294            }
295
296            intent.setFlags((intent.getFlags()&~Intent.FLAG_ACTIVITY_RESET_TASK_IF_NEEDED)
297                    | Intent.FLAG_ACTIVITY_NEW_TASK);
298            final ResolveInfo resolveInfo = pm.resolveActivity(intent, 0);
299            if (resolveInfo != null) {
300                final ActivityInfo activityInfo = resolveInfo.activityInfo;
301                final String title = activityInfo.loadLabel(pm).toString();
302                Drawable icon = activityInfo.loadIcon(pm);
303
304                if (title != null && title.length() > 0 && icon != null) {
305                    final TextView tv = mIcons[index];
306                    tv.setText(title);
307                    icon = iconUtilities.createIconDrawable(icon);
308                    tv.setCompoundDrawables(null, icon, null, null);
309                    RecentTag tag = new RecentTag();
310                    tag.info = info;
311                    tag.intent = intent;
312                    tv.setTag(tag);
313                    tv.setVisibility(View.VISIBLE);
314                    tv.setPressed(false);
315                    tv.clearFocus();
316                    ++index;
317                }
318            }
319        }
320
321        // handle the case of "no icons to show"
322        mNoAppsText.setVisibility((index == 0) ? View.VISIBLE : View.GONE);
323
324        // hide the rest
325        for (; index < NUM_BUTTONS; ++index) {
326            mIcons[index].setVisibility(View.GONE);
327        }
328    }
329
330    /**
331     * This is the listener for the ACTION_CLOSE_SYSTEM_DIALOGS intent.  It's an indication that
332     * we should close ourselves immediately, in order to allow a higher-priority UI to take over
333     * (e.g. phone call received).
334     */
335    private BroadcastReceiver mBroadcastReceiver = new BroadcastReceiver() {
336        @Override
337        public void onReceive(Context context, Intent intent) {
338            String action = intent.getAction();
339            if (Intent.ACTION_CLOSE_SYSTEM_DIALOGS.equals(action)) {
340                String reason = intent.getStringExtra(PhoneWindowManager.SYSTEM_DIALOG_REASON_KEY);
341                if (! PhoneWindowManager.SYSTEM_DIALOG_REASON_RECENT_APPS.equals(reason)) {
342                    dismiss();
343                }
344            }
345        }
346    };
347}
348