1/*
2 * Copyright (C) 2013 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.settings.accessibility;
18
19import android.accessibilityservice.AccessibilityServiceInfo;
20import android.app.Activity;
21import android.app.AlertDialog;
22import android.app.Dialog;
23import android.app.admin.DevicePolicyManager;
24import android.content.ComponentName;
25import android.content.Context;
26import android.content.DialogInterface;
27import android.content.Intent;
28import android.content.pm.ResolveInfo;
29import android.net.Uri;
30import android.os.Bundle;
31import android.os.Handler;
32import android.os.UserHandle;
33import android.provider.Settings;
34import android.text.TextUtils;
35import android.view.LayoutInflater;
36import android.view.MotionEvent;
37import android.view.View;
38import android.view.accessibility.AccessibilityManager;
39import android.widget.ImageView;
40import android.widget.LinearLayout;
41import android.widget.TextView;
42import android.widget.Toast;
43
44import com.android.internal.logging.MetricsLogger;
45import com.android.internal.widget.LockPatternUtils;
46import com.android.settings.ConfirmDeviceCredentialActivity;
47import com.android.settings.R;
48import com.android.settings.widget.ToggleSwitch;
49import com.android.settings.widget.ToggleSwitch.OnBeforeCheckedChangeListener;
50
51import java.util.Collections;
52import java.util.HashSet;
53import java.util.List;
54import java.util.Set;
55
56public class ToggleAccessibilityServicePreferenceFragment
57        extends ToggleFeaturePreferenceFragment implements DialogInterface.OnClickListener {
58
59    private static final int DIALOG_ID_ENABLE_WARNING = 1;
60    private static final int DIALOG_ID_DISABLE_WARNING = 2;
61
62    public static final int ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION = 1;
63
64    private LockPatternUtils mLockPatternUtils;
65
66    private final SettingsContentObserver mSettingsContentObserver =
67            new SettingsContentObserver(new Handler()) {
68            @Override
69                public void onChange(boolean selfChange, Uri uri) {
70                    updateSwitchBarToggleSwitch();
71                }
72            };
73
74    private ComponentName mComponentName;
75
76    private int mShownDialogId;
77
78    @Override
79    protected int getMetricsCategory() {
80        return MetricsLogger.ACCESSIBILITY_SERVICE;
81    }
82
83    @Override
84    public void onCreate(Bundle savedInstanceState) {
85        super.onCreate(savedInstanceState);
86        mLockPatternUtils = new LockPatternUtils(getActivity());
87    }
88
89    @Override
90    public void onResume() {
91        mSettingsContentObserver.register(getContentResolver());
92        updateSwitchBarToggleSwitch();
93        super.onResume();
94    }
95
96    @Override
97    public void onPause() {
98        mSettingsContentObserver.unregister(getContentResolver());
99        super.onPause();
100    }
101
102    @Override
103    public void onPreferenceToggled(String preferenceKey, boolean enabled) {
104        // Parse the enabled services.
105        Set<ComponentName> enabledServices = AccessibilityUtils.getEnabledServicesFromSettings(
106                getActivity());
107
108        if (enabledServices == (Set<?>) Collections.emptySet()) {
109            enabledServices = new HashSet<ComponentName>();
110        }
111
112        // Determine enabled services and accessibility state.
113        ComponentName toggledService = ComponentName.unflattenFromString(preferenceKey);
114        boolean accessibilityEnabled = false;
115        if (enabled) {
116            enabledServices.add(toggledService);
117            // Enabling at least one service enables accessibility.
118            accessibilityEnabled = true;
119        } else {
120            enabledServices.remove(toggledService);
121            // Check how many enabled and installed services are present.
122            Set<ComponentName> installedServices = AccessibilitySettings.sInstalledServices;
123            for (ComponentName enabledService : enabledServices) {
124                if (installedServices.contains(enabledService)) {
125                    // Disabling the last service disables accessibility.
126                    accessibilityEnabled = true;
127                    break;
128                }
129            }
130        }
131
132        // Update the enabled services setting.
133        StringBuilder enabledServicesBuilder = new StringBuilder();
134        // Keep the enabled services even if they are not installed since we
135        // have no way to know whether the application restore process has
136        // completed. In general the system should be responsible for the
137        // clean up not settings.
138        for (ComponentName enabledService : enabledServices) {
139            enabledServicesBuilder.append(enabledService.flattenToString());
140            enabledServicesBuilder.append(
141                    AccessibilitySettings.ENABLED_ACCESSIBILITY_SERVICES_SEPARATOR);
142        }
143        final int enabledServicesBuilderLength = enabledServicesBuilder.length();
144        if (enabledServicesBuilderLength > 0) {
145            enabledServicesBuilder.deleteCharAt(enabledServicesBuilderLength - 1);
146        }
147        Settings.Secure.putString(getContentResolver(),
148                Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES,
149                enabledServicesBuilder.toString());
150
151        // Update accessibility enabled.
152        Settings.Secure.putInt(getContentResolver(),
153                Settings.Secure.ACCESSIBILITY_ENABLED, accessibilityEnabled ? 1 : 0);
154    }
155
156    // IMPORTANT: Refresh the info since there are dynamically changing
157    // capabilities. For
158    // example, before JellyBean MR2 the user was granting the explore by touch
159    // one.
160    private AccessibilityServiceInfo getAccessibilityServiceInfo() {
161        List<AccessibilityServiceInfo> serviceInfos = AccessibilityManager.getInstance(
162                getActivity()).getInstalledAccessibilityServiceList();
163        final int serviceInfoCount = serviceInfos.size();
164        for (int i = 0; i < serviceInfoCount; i++) {
165            AccessibilityServiceInfo serviceInfo = serviceInfos.get(i);
166            ResolveInfo resolveInfo = serviceInfo.getResolveInfo();
167            if (mComponentName.getPackageName().equals(resolveInfo.serviceInfo.packageName)
168                    && mComponentName.getClassName().equals(resolveInfo.serviceInfo.name)) {
169                return serviceInfo;
170            }
171        }
172        return null;
173    }
174
175    @Override
176    public Dialog onCreateDialog(int dialogId) {
177        switch (dialogId) {
178            case DIALOG_ID_ENABLE_WARNING: {
179                mShownDialogId = DIALOG_ID_ENABLE_WARNING;
180
181                final AccessibilityServiceInfo info = getAccessibilityServiceInfo();
182                if (info == null) {
183                    return null;
184                }
185
186                final AlertDialog ad = new AlertDialog.Builder(getActivity())
187                        .setTitle(getString(R.string.enable_service_title,
188                                info.getResolveInfo().loadLabel(getPackageManager())))
189                        .setView(createEnableDialogContentView(info))
190                        .setCancelable(true)
191                        .setPositiveButton(android.R.string.ok, this)
192                        .setNegativeButton(android.R.string.cancel, this)
193                        .create();
194
195                final View.OnTouchListener filterTouchListener = new View.OnTouchListener() {
196                    @Override
197                    public boolean onTouch(View v, MotionEvent event) {
198                        // Filter obscured touches by consuming them.
199                        if ((event.getFlags() & MotionEvent.FLAG_WINDOW_IS_OBSCURED) != 0) {
200                            if (event.getAction() == MotionEvent.ACTION_UP) {
201                                Toast.makeText(v.getContext(), R.string.touch_filtered_warning,
202                                        Toast.LENGTH_SHORT).show();
203                            }
204                            return true;
205                        }
206                        return false;
207                    }
208                };
209
210                ad.create();
211                ad.getButton(AlertDialog.BUTTON_POSITIVE).setOnTouchListener(filterTouchListener);
212                return ad;
213            }
214            case DIALOG_ID_DISABLE_WARNING: {
215                mShownDialogId = DIALOG_ID_DISABLE_WARNING;
216                AccessibilityServiceInfo info = getAccessibilityServiceInfo();
217                if (info == null) {
218                    return null;
219                }
220                return new AlertDialog.Builder(getActivity())
221                        .setTitle(getString(R.string.disable_service_title,
222                                info.getResolveInfo().loadLabel(getPackageManager())))
223                        .setMessage(getString(R.string.disable_service_message,
224                                info.getResolveInfo().loadLabel(getPackageManager())))
225                        .setCancelable(true)
226                        .setPositiveButton(android.R.string.ok, this)
227                        .setNegativeButton(android.R.string.cancel, this)
228                        .create();
229            }
230            default: {
231                throw new IllegalArgumentException();
232            }
233        }
234    }
235
236    private void updateSwitchBarToggleSwitch() {
237        final String settingValue = Settings.Secure.getString(getContentResolver(),
238                Settings.Secure.ENABLED_ACCESSIBILITY_SERVICES);
239        final boolean checked = settingValue != null
240                && settingValue.contains(mComponentName.flattenToString());
241        mSwitchBar.setCheckedInternal(checked);
242    }
243
244    private View createEnableDialogContentView(AccessibilityServiceInfo info) {
245        LayoutInflater inflater = (LayoutInflater) getSystemService(
246                Context.LAYOUT_INFLATER_SERVICE);
247
248        View content = inflater.inflate(R.layout.enable_accessibility_service_dialog_content,
249                null);
250
251        TextView encryptionWarningView = (TextView) content.findViewById(
252                R.id.encryption_warning);
253        if (LockPatternUtils.isDeviceEncrypted()) {
254            String text = getString(R.string.enable_service_encryption_warning,
255                    info.getResolveInfo().loadLabel(getPackageManager()));
256            encryptionWarningView.setText(text);
257            encryptionWarningView.setVisibility(View.VISIBLE);
258        } else {
259            encryptionWarningView.setVisibility(View.GONE);
260        }
261
262        TextView capabilitiesHeaderView = (TextView) content.findViewById(
263                R.id.capabilities_header);
264        capabilitiesHeaderView.setText(getString(R.string.capabilities_list_title,
265                info.getResolveInfo().loadLabel(getPackageManager())));
266
267        LinearLayout capabilitiesView = (LinearLayout) content.findViewById(R.id.capabilities);
268
269        // This capability is implicit for all services.
270        View capabilityView = inflater.inflate(
271                com.android.internal.R.layout.app_permission_item_old, null);
272
273        ImageView imageView = (ImageView) capabilityView.findViewById(
274                com.android.internal.R.id.perm_icon);
275        imageView.setImageDrawable(getActivity().getDrawable(
276                com.android.internal.R.drawable.ic_text_dot));
277
278        TextView labelView = (TextView) capabilityView.findViewById(
279                com.android.internal.R.id.permission_group);
280        labelView.setText(getString(R.string.capability_title_receiveAccessibilityEvents));
281
282        TextView descriptionView = (TextView) capabilityView.findViewById(
283                com.android.internal.R.id.permission_list);
284        descriptionView.setText(getString(R.string.capability_desc_receiveAccessibilityEvents));
285
286        List<AccessibilityServiceInfo.CapabilityInfo> capabilities =
287                info.getCapabilityInfos();
288
289        capabilitiesView.addView(capabilityView);
290
291        // Service specific capabilities.
292        final int capabilityCount = capabilities.size();
293        for (int i = 0; i < capabilityCount; i++) {
294            AccessibilityServiceInfo.CapabilityInfo capability = capabilities.get(i);
295
296            capabilityView = inflater.inflate(
297                    com.android.internal.R.layout.app_permission_item_old, null);
298
299            imageView = (ImageView) capabilityView.findViewById(
300                    com.android.internal.R.id.perm_icon);
301            imageView.setImageDrawable(getActivity().getDrawable(
302                    com.android.internal.R.drawable.ic_text_dot));
303
304            labelView = (TextView) capabilityView.findViewById(
305                    com.android.internal.R.id.permission_group);
306            labelView.setText(getString(capability.titleResId));
307
308            descriptionView = (TextView) capabilityView.findViewById(
309                    com.android.internal.R.id.permission_list);
310            descriptionView.setText(getString(capability.descResId));
311
312            capabilitiesView.addView(capabilityView);
313        }
314
315        return content;
316    }
317
318    @Override
319    public void onActivityResult(int requestCode, int resultCode, Intent data) {
320        if (requestCode == ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION) {
321            if (resultCode == Activity.RESULT_OK) {
322                handleConfirmServiceEnabled(true);
323                // The user confirmed that they accept weaker encryption when
324                // enabling the accessibility service, so change encryption.
325                // Since we came here asynchronously, check encryption again.
326                if (LockPatternUtils.isDeviceEncrypted()) {
327                    mLockPatternUtils.clearEncryptionPassword();
328                    Settings.Global.putInt(getContentResolver(),
329                            Settings.Global.REQUIRE_PASSWORD_TO_DECRYPT, 0);
330                }
331            } else {
332                handleConfirmServiceEnabled(false);
333            }
334        }
335    }
336
337    @Override
338    public void onClick(DialogInterface dialog, int which) {
339        final boolean checked;
340        switch (which) {
341            case DialogInterface.BUTTON_POSITIVE:
342                if (mShownDialogId == DIALOG_ID_ENABLE_WARNING) {
343                    if (LockPatternUtils.isDeviceEncrypted()) {
344                        String title = createConfirmCredentialReasonMessage();
345                        Intent intent = ConfirmDeviceCredentialActivity.createIntent(title, null);
346                        startActivityForResult(intent,
347                                ACTIVITY_REQUEST_CONFIRM_CREDENTIAL_FOR_WEAKER_ENCRYPTION);
348                    } else {
349                        handleConfirmServiceEnabled(true);
350                    }
351                } else {
352                    handleConfirmServiceEnabled(false);
353                }
354                break;
355            case DialogInterface.BUTTON_NEGATIVE:
356                checked = (mShownDialogId == DIALOG_ID_DISABLE_WARNING);
357                handleConfirmServiceEnabled(checked);
358                break;
359            default:
360                throw new IllegalArgumentException();
361        }
362    }
363
364    private void handleConfirmServiceEnabled(boolean confirmed) {
365        mSwitchBar.setCheckedInternal(confirmed);
366        getArguments().putBoolean(AccessibilitySettings.EXTRA_CHECKED, confirmed);
367        onPreferenceToggled(mPreferenceKey, confirmed);
368    }
369
370    private String createConfirmCredentialReasonMessage() {
371        int resId = R.string.enable_service_password_reason;
372        switch (mLockPatternUtils.getKeyguardStoredPasswordQuality(UserHandle.myUserId())) {
373            case DevicePolicyManager.PASSWORD_QUALITY_SOMETHING: {
374                resId = R.string.enable_service_pattern_reason;
375            } break;
376            case DevicePolicyManager.PASSWORD_QUALITY_NUMERIC:
377            case DevicePolicyManager.PASSWORD_QUALITY_NUMERIC_COMPLEX: {
378                resId = R.string.enable_service_pin_reason;
379            } break;
380        }
381        return getString(resId, getAccessibilityServiceInfo().getResolveInfo()
382                .loadLabel(getPackageManager()));
383    }
384
385    @Override
386    protected void onInstallSwitchBarToggleSwitch() {
387        super.onInstallSwitchBarToggleSwitch();
388        mToggleSwitch.setOnBeforeCheckedChangeListener(new OnBeforeCheckedChangeListener() {
389                @Override
390            public boolean onBeforeCheckedChanged(ToggleSwitch toggleSwitch, boolean checked) {
391                if (checked) {
392                    mSwitchBar.setCheckedInternal(false);
393                    getArguments().putBoolean(AccessibilitySettings.EXTRA_CHECKED, false);
394                    showDialog(DIALOG_ID_ENABLE_WARNING);
395                } else {
396                    mSwitchBar.setCheckedInternal(true);
397                    getArguments().putBoolean(AccessibilitySettings.EXTRA_CHECKED, true);
398                    showDialog(DIALOG_ID_DISABLE_WARNING);
399                }
400                return true;
401            }
402        });
403    }
404
405    @Override
406    protected void onProcessArguments(Bundle arguments) {
407        super.onProcessArguments(arguments);
408        // Settings title and intent.
409        String settingsTitle = arguments.getString(AccessibilitySettings.EXTRA_SETTINGS_TITLE);
410        String settingsComponentName = arguments.getString(
411                AccessibilitySettings.EXTRA_SETTINGS_COMPONENT_NAME);
412        if (!TextUtils.isEmpty(settingsTitle) && !TextUtils.isEmpty(settingsComponentName)) {
413            Intent settingsIntent = new Intent(Intent.ACTION_MAIN).setComponent(
414                    ComponentName.unflattenFromString(settingsComponentName.toString()));
415            if (!getPackageManager().queryIntentActivities(settingsIntent, 0).isEmpty()) {
416                mSettingsTitle = settingsTitle;
417                mSettingsIntent = settingsIntent;
418                setHasOptionsMenu(true);
419            }
420        }
421
422        mComponentName = arguments.getParcelable(AccessibilitySettings.EXTRA_COMPONENT_NAME);
423    }
424}
425