1/*
2 * Copyright (C) 2011 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.dialer.util;
18
19import android.app.LoaderManager.LoaderCallbacks;
20import android.content.Context;
21import android.content.Loader;
22import android.os.Bundle;
23
24/**
25 * A {@link Loader} only used to make use of the {@link android.app.Fragment#setStartDeferred}
26 * feature from an old-style fragment which doesn't use {@link Loader}s to load data.
27 *
28 * This loader never delivers results.  A caller fragment must destroy it when deferred fragments
29 * should be started.
30 */
31public class EmptyLoader extends Loader<Object> {
32    public EmptyLoader(Context context) {
33        super(context);
34    }
35
36    /**
37     * {@link LoaderCallbacks} which just generates {@link EmptyLoader}.  {@link #onLoadFinished}
38     * and {@link #onLoaderReset} are no-op.
39     */
40    public static class Callback implements LoaderCallbacks<Object> {
41        private final Context mContext;
42
43        public Callback(Context context) {
44            mContext = context.getApplicationContext();
45        }
46
47        @Override
48        public Loader<Object> onCreateLoader(int id, Bundle args) {
49            return new EmptyLoader(mContext);
50        }
51
52        @Override
53        public void onLoadFinished(Loader<Object> loader, Object data) {
54        }
55
56        @Override
57        public void onLoaderReset(Loader<Object> loader) {
58        }
59    }
60}
61