ActionBarPolicy.java revision 4207fda51babb3892652fcdc901295c81876a38f 
1/*
2 * Copyright (C) 2012 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.internal.view;
18
19import com.android.internal.R;
20
21import android.content.Context;
22import android.content.res.Configuration;
23import android.content.res.Resources;
24import android.content.res.TypedArray;
25import android.os.Build;
26import android.view.ViewConfiguration;
27
28/**
29 * Allows components to query for various configuration policy decisions
30 * about how the action bar should lay out and behave on the current device.
31 */
32public class ActionBarPolicy {
33    private Context mContext;
34
35    public static ActionBarPolicy get(Context context) {
36        return new ActionBarPolicy(context);
37    }
38
39    private ActionBarPolicy(Context context) {
40        mContext = context;
41    }
42
43    public int getMaxActionButtons() {
44        return mContext.getResources().getInteger(R.integer.max_action_buttons);
45    }
46
47    public boolean showsOverflowMenuButton() {
48        return !ViewConfiguration.get(mContext).hasPermanentMenuKey() ||
49                ((mContext.getResources().getConfiguration().uiMode &
50                        Configuration.UI_MODE_TYPE_TELEVISION) ==
51                        Configuration.UI_MODE_TYPE_TELEVISION);
52    }
53
54    public int getEmbeddedMenuWidthLimit() {
55        return mContext.getResources().getDisplayMetrics().widthPixels / 2;
56    }
57
58    public boolean hasEmbeddedTabs() {
59        final int targetSdk = mContext.getApplicationInfo().targetSdkVersion;
60        if (targetSdk >= Build.VERSION_CODES.JELLY_BEAN) {
61            return mContext.getResources().getBoolean(R.bool.action_bar_embed_tabs);
62        }
63
64        // The embedded tabs policy changed in Jellybean; give older apps the old policy
65        // so they get what they expect.
66        return mContext.getResources().getBoolean(R.bool.action_bar_embed_tabs_pre_jb);
67    }
68
69    public int getTabContainerHeight() {
70        TypedArray a = mContext.obtainStyledAttributes(null, R.styleable.ActionBar,
71                com.android.internal.R.attr.actionBarStyle, 0);
72        int height = a.getLayoutDimension(R.styleable.ActionBar_height, 0);
73        Resources r = mContext.getResources();
74        if (!hasEmbeddedTabs()) {
75            // Stacked tabs; limit the height
76            height = Math.min(height,
77                    r.getDimensionPixelSize(R.dimen.action_bar_stacked_max_height));
78        }
79        a.recycle();
80        return height;
81    }
82
83    public boolean enableHomeButtonByDefault() {
84        // Older apps get the home button interaction enabled by default.
85        // Newer apps need to enable it explicitly.
86        return mContext.getApplicationInfo().targetSdkVersion <
87                Build.VERSION_CODES.ICE_CREAM_SANDWICH;
88    }
89
90    public int getStackedTabMaxWidth() {
91        return mContext.getResources().getDimensionPixelSize(
92                R.dimen.action_bar_stacked_tab_max_width);
93    }
94}
95