1 /*
2  * Copyright 2018 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 
17 package androidx.leanback.preference;
18 
19 import android.os.Bundle;
20 
21 import androidx.fragment.app.Fragment;
22 import androidx.preference.DialogPreference;
23 
24 /**
25  * A fragment that shows {@link DialogPreference}, for example {@link
26  * androidx.preference.ListPreference} or {@link androidx.preference.MultiSelectListPreference}.
27  */
28 public class LeanbackPreferenceDialogFragmentCompat extends Fragment {
29 
30     public static final String ARG_KEY = "key";
31 
32     private DialogPreference mPreference;
33 
LeanbackPreferenceDialogFragmentCompat()34     public LeanbackPreferenceDialogFragmentCompat() {
35         LeanbackPreferenceFragmentTransitionHelperApi21.addTransitions(this);
36     }
37 
38     @Override
onCreate(Bundle savedInstanceState)39     public void onCreate(Bundle savedInstanceState) {
40         super.onCreate(savedInstanceState);
41 
42         final Fragment rawFragment = getTargetFragment();
43         if (!(rawFragment instanceof DialogPreference.TargetFragment)) {
44             throw new IllegalStateException("Target fragment " + rawFragment
45                     + " must implement TargetFragment interface");
46         }
47     }
48 
49     /**
50      * The {@link DialogPreference} that this dialog is showing.
51      * @return The {@link DialogPreference} that this dialog is showing.
52      */
getPreference()53     public DialogPreference getPreference() {
54         if (mPreference == null) {
55             final String key = getArguments().getString(ARG_KEY);
56             final DialogPreference.TargetFragment fragment =
57                     (DialogPreference.TargetFragment) getTargetFragment();
58             mPreference = (DialogPreference) fragment.findPreference(key);
59         }
60         return mPreference;
61     }
62 }
63