RestrictedSettingsFragment.java revision 8b72e563ec882839ef97baec17581af097abf8fa 
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;
18
19import android.app.Activity;
20import android.app.admin.DevicePolicyManager;
21import android.content.BroadcastReceiver;
22import android.content.Context;
23import android.content.Intent;
24import android.content.IntentFilter;
25import android.content.RestrictionsManager;
26import android.os.Bundle;
27import android.os.PersistableBundle;
28import android.os.UserHandle;
29import android.os.UserManager;
30import android.view.Gravity;
31import android.view.View;
32import android.widget.TextView;
33
34import com.android.settingslib.RestrictedLockUtils;
35
36import static com.android.settingslib.RestrictedLockUtils.EnforcedAdmin;
37
38/**
39 * Base class for settings screens that should be pin protected when in restricted mode or
40 * that will display an admin support message in case an admin has disabled the options.
41 * The constructor for this class will take the restriction key that this screen should be
42 * locked by.  If {@link RestrictionsManager.hasRestrictionsProvider()} and
43 * {@link UserManager.hasUserRestriction()}, then the user will have to enter the restrictions
44 * pin before seeing the Settings screen.
45 *
46 * If this settings screen should be pin protected whenever
47 * {@link RestrictionsManager.hasRestrictionsProvider()} returns true, pass in
48 * {@link RESTRICT_IF_OVERRIDABLE} to the constructor instead of a restrictions key.
49 */
50public abstract class RestrictedSettingsFragment extends SettingsPreferenceFragment {
51
52    protected static final String RESTRICT_IF_OVERRIDABLE = "restrict_if_overridable";
53
54    // No RestrictedSettingsFragment screens should use this number in startActivityForResult.
55    private static final int REQUEST_PIN_CHALLENGE = 12309;
56
57    private static final String KEY_CHALLENGE_SUCCEEDED = "chsc";
58    private static final String KEY_CHALLENGE_REQUESTED = "chrq";
59
60    // If the restriction PIN is entered correctly.
61    private boolean mChallengeSucceeded;
62    private boolean mChallengeRequested;
63
64    private UserManager mUserManager;
65    private RestrictionsManager mRestrictionsManager;
66
67    private final String mRestrictionKey;
68    private View mAdminSupportDetails;
69    private EnforcedAdmin mEnforcedAdmin;
70    private TextView mEmptyTextView;
71
72    private boolean mOnlyAvailableForAdmins = false;
73    private boolean mIsAdminUser;
74
75    // Receiver to clear pin status when the screen is turned off.
76    private BroadcastReceiver mScreenOffReceiver = new BroadcastReceiver() {
77        @Override
78        public void onReceive(Context context, Intent intent) {
79            if (!mChallengeRequested) {
80                mChallengeSucceeded = false;
81                mChallengeRequested = false;
82            }
83        }
84    };
85
86    /**
87     * @param restrictionKey The restriction key to check before pin protecting
88     *            this settings page. Pass in {@link RESTRICT_IF_OVERRIDABLE} if it should
89     *            be protected whenever a restrictions provider is set. Pass in
90     *            null if it should never be protected.
91     */
92    public RestrictedSettingsFragment(String restrictionKey) {
93        mRestrictionKey = restrictionKey;
94    }
95
96    @Override
97    public void onCreate(Bundle icicle) {
98        super.onCreate(icicle);
99
100        mRestrictionsManager = (RestrictionsManager) getSystemService(Context.RESTRICTIONS_SERVICE);
101        mUserManager = (UserManager) getSystemService(Context.USER_SERVICE);
102        mIsAdminUser = mUserManager.isAdminUser();
103
104        if (icicle != null) {
105            mChallengeSucceeded = icicle.getBoolean(KEY_CHALLENGE_SUCCEEDED, false);
106            mChallengeRequested = icicle.getBoolean(KEY_CHALLENGE_REQUESTED, false);
107        }
108
109        IntentFilter offFilter = new IntentFilter(Intent.ACTION_SCREEN_OFF);
110        offFilter.addAction(Intent.ACTION_USER_PRESENT);
111        getActivity().registerReceiver(mScreenOffReceiver, offFilter);
112    }
113
114    @Override
115    public void onActivityCreated(Bundle savedInstanceState) {
116        super.onActivityCreated(savedInstanceState);
117        mAdminSupportDetails = initAdminSupportDetailsView();
118        mEmptyTextView = initEmptyTextView();
119    }
120
121    @Override
122    public void onSaveInstanceState(Bundle outState) {
123        super.onSaveInstanceState(outState);
124
125        if (getActivity().isChangingConfigurations()) {
126            outState.putBoolean(KEY_CHALLENGE_REQUESTED, mChallengeRequested);
127            outState.putBoolean(KEY_CHALLENGE_SUCCEEDED, mChallengeSucceeded);
128        }
129    }
130
131    @Override
132    public void onResume() {
133        super.onResume();
134
135        if (shouldBeProviderProtected(mRestrictionKey)) {
136            ensurePin();
137        }
138    }
139
140    @Override
141    public void onDestroy() {
142        getActivity().unregisterReceiver(mScreenOffReceiver);
143        super.onDestroy();
144    }
145
146    @Override
147    public void onActivityResult(int requestCode, int resultCode, Intent data) {
148        if (requestCode == REQUEST_PIN_CHALLENGE) {
149            if (resultCode == Activity.RESULT_OK) {
150                mChallengeSucceeded = true;
151                mChallengeRequested = false;
152            } else {
153                mChallengeSucceeded = false;
154            }
155            return;
156        }
157
158        super.onActivityResult(requestCode, resultCode, data);
159    }
160
161    private void ensurePin() {
162        if (!mChallengeSucceeded && !mChallengeRequested
163                && mRestrictionsManager.hasRestrictionsProvider()) {
164            Intent intent = mRestrictionsManager.createLocalApprovalIntent();
165            if (intent != null) {
166                mChallengeRequested = true;
167                mChallengeSucceeded = false;
168                PersistableBundle request = new PersistableBundle();
169                request.putString(RestrictionsManager.REQUEST_KEY_MESSAGE,
170                        getResources().getString(R.string.restr_pin_enter_admin_pin));
171                intent.putExtra(RestrictionsManager.EXTRA_REQUEST_BUNDLE, request);
172                startActivityForResult(intent, REQUEST_PIN_CHALLENGE);
173            }
174        }
175    }
176
177    /**
178     * Returns true if this activity is restricted, but no restrictions provider has been set.
179     * Used to determine if the settings UI should disable UI.
180     */
181    protected boolean isRestrictedAndNotProviderProtected() {
182        if (mRestrictionKey == null || RESTRICT_IF_OVERRIDABLE.equals(mRestrictionKey)) {
183            return false;
184        }
185        return mUserManager.hasUserRestriction(mRestrictionKey)
186                && !mRestrictionsManager.hasRestrictionsProvider();
187    }
188
189    protected boolean hasChallengeSucceeded() {
190        return (mChallengeRequested && mChallengeSucceeded) || !mChallengeRequested;
191    }
192
193    /**
194     * Returns true if this restrictions key is locked down.
195     */
196    protected boolean shouldBeProviderProtected(String restrictionKey) {
197        if (restrictionKey == null) {
198            return false;
199        }
200        boolean restricted = RESTRICT_IF_OVERRIDABLE.equals(restrictionKey)
201                || mUserManager.hasUserRestriction(mRestrictionKey);
202        return restricted && mRestrictionsManager.hasRestrictionsProvider();
203    }
204
205    private View initAdminSupportDetailsView() {
206        return getActivity().findViewById(R.id.admin_support_details);
207    }
208
209    protected TextView initEmptyTextView() {
210        TextView emptyView = (TextView) getActivity().findViewById(android.R.id.empty);
211        return emptyView;
212    }
213
214    public EnforcedAdmin getRestrictionEnforcedAdmin() {
215        mEnforcedAdmin = RestrictedLockUtils.checkIfRestrictionEnforced(getActivity(),
216                mRestrictionKey, UserHandle.myUserId());
217        if (mEnforcedAdmin != null && mEnforcedAdmin.userId == UserHandle.USER_NULL) {
218            mEnforcedAdmin.userId = UserHandle.myUserId();
219        }
220        return mEnforcedAdmin;
221    }
222
223    public TextView getEmptyTextView() {
224        return mEmptyTextView;
225    }
226
227    @Override
228    protected void onDataSetChanged() {
229        highlightPreferenceIfNeeded();
230        if (mAdminSupportDetails != null && isUiRestrictedByOnlyAdmin()) {
231            final EnforcedAdmin admin = getRestrictionEnforcedAdmin();
232            ShowAdminSupportDetailsDialog.setAdminSupportDetails(getActivity(),
233                    mAdminSupportDetails, admin, false);
234            setEmptyView(mAdminSupportDetails);
235        } else if (mEmptyTextView != null) {
236            setEmptyView(mEmptyTextView);
237        }
238        super.onDataSetChanged();
239    }
240
241    public void setIfOnlyAvailableForAdmins(boolean onlyForAdmins) {
242        mOnlyAvailableForAdmins = onlyForAdmins;
243    }
244
245    /**
246     * Returns whether restricted or actionable UI elements should be removed or disabled.
247     */
248    protected boolean isUiRestricted() {
249        return isRestrictedAndNotProviderProtected() || !hasChallengeSucceeded()
250                || (!mIsAdminUser && mOnlyAvailableForAdmins);
251    }
252
253    protected boolean isUiRestrictedByOnlyAdmin() {
254        return isUiRestricted() && !mUserManager.hasBaseUserRestriction(mRestrictionKey,
255                UserHandle.of(UserHandle.myUserId())) && (mIsAdminUser || !mOnlyAvailableForAdmins);
256    }
257}
258