FallbackThemeWrapper.java revision d3ffc713be68823409d5dc6d2d44bb21bde5bfd0 
1/*
2 * Copyright (C) 2017 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.setupwizardlib.util;
18
19import android.content.Context;
20import android.content.res.Resources.Theme;
21import android.support.annotation.StyleRes;
22import android.view.ContextThemeWrapper;
23
24/**
25 * Same as {@link ContextThemeWrapper}, but the base context's theme attributes take precedence
26 * over the wrapper context's. This is used to provide default values for theme attributes
27 * referenced in layouts, to remove the risk of crashing the client because of using the wrong
28 * theme.
29 */
30public class FallbackThemeWrapper extends ContextThemeWrapper {
31
32    /**
33     * Creates a new context wrapper with the specified theme.
34     *
35     * The specified theme will be applied as fallbacks to the base context's theme. Any attributes
36     * defined in the base context's theme will retain their original values. Otherwise values in
37     * {@code themeResId} will be used.
38     *
39     * @param base The base context.
40     * @param themeResId The theme to use as fallback.
41     */
42    public FallbackThemeWrapper(Context base, @StyleRes int themeResId) {
43        super(base, themeResId);
44    }
45
46    /**
47     * {@inheritDoc}
48     */
49    @Override
50    protected void onApplyThemeResource(Theme theme, int resId, boolean first) {
51        theme.applyStyle(resId, false /* force */);
52    }
53}
54