ActionBarPolicy.java revision b8139af3dcae80c0030afd0354dc424a7c72c3d9 
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.Resources;
23import android.content.res.TypedArray;
24import android.os.Build;
25import android.view.ViewConfiguration;
26
27/**
28 * Allows components to query for various configuration policy decisions
29 * about how the action bar should lay out and behave on the current device.
30 */
31public class ActionBarPolicy {
32    private Context mContext;
33
34    public static ActionBarPolicy get(Context context) {
35        return new ActionBarPolicy(context);
36    }
37
38    private ActionBarPolicy(Context context) {
39        mContext = context;
40    }
41
42    public int getMaxActionButtons() {
43        return mContext.getResources().getInteger(R.integer.max_action_buttons);
44    }
45
46    public boolean showsOverflowMenuButton() {
47        return !ViewConfiguration.get(mContext).hasPermanentMenuKey();
48    }
49
50    public int getEmbeddedMenuWidthLimit() {
51        return mContext.getResources().getDisplayMetrics().widthPixels / 2;
52    }
53
54    public boolean hasEmbeddedTabs() {
55        final int targetSdk = mContext.getApplicationInfo().targetSdkVersion;
56        if (targetSdk >= Build.VERSION_CODES.JELLY_BEAN) {
57            return mContext.getResources().getBoolean(R.bool.action_bar_embed_tabs);
58        }
59
60        // The embedded tabs policy changed in Jellybean; give older apps the old policy
61        // so they get what they expect.
62        return mContext.getResources().getBoolean(R.bool.action_bar_embed_tabs_pre_jb);
63    }
64
65    public int getTabContainerHeight() {
66        TypedArray a = mContext.obtainStyledAttributes(null, R.styleable.ActionBar,
67                com.android.internal.R.attr.actionBarStyle, 0);
68        int height = a.getLayoutDimension(R.styleable.ActionBar_height, 0);
69        Resources r = mContext.getResources();
70        if (!hasEmbeddedTabs()) {
71            // Stacked tabs; limit the height
72            height = Math.min(height,
73                    r.getDimensionPixelSize(R.dimen.action_bar_stacked_max_height));
74        }
75        a.recycle();
76        return height;
77    }
78
79    public boolean enableHomeButtonByDefault() {
80        // Older apps get the home button interaction enabled by default.
81        // Newer apps need to enable it explicitly.
82        return mContext.getApplicationInfo().targetSdkVersion <
83                Build.VERSION_CODES.ICE_CREAM_SANDWICH;
84    }
85
86    public int getStackedTabMaxWidth() {
87        return mContext.getResources().getDimensionPixelSize(
88                R.dimen.action_bar_stacked_tab_max_width);
89    }
90}
91