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      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 
     17 package androidx.appcompat.view;
     18 
     19 import static androidx.annotation.RestrictTo.Scope.LIBRARY_GROUP;
     20 
     21 import android.content.Context;
     22 import android.content.res.Configuration;
     23 import android.content.res.Resources;
     24 import android.content.res.TypedArray;
     25 import android.os.Build;
     26 import android.view.ViewConfiguration;
     27 
     28 import androidx.annotation.RestrictTo;
     29 import androidx.appcompat.R;
     30 
     31 /**
     32  * Allows components to query for various configuration policy decisions about how the action bar
     33  * should lay out and behave on the current device.
     34  *
     35  * @hide
     36  */
     37 @RestrictTo(LIBRARY_GROUP)
     38 public class ActionBarPolicy {
     39 
     40     private Context mContext;
     41 
     42     public static ActionBarPolicy get(Context context) {
     43         return new ActionBarPolicy(context);
     44     }
     45 
     46     private ActionBarPolicy(Context context) {
     47         mContext = context;
     48     }
     49 
     50     /**
     51      * Returns the maximum number of action buttons that should be permitted within an action
     52      * bar/action mode. This will be used to determine how many showAsAction="ifRoom" items can fit.
     53      * "always" items can override this.
     54      */
     55     public int getMaxActionButtons() {
     56         final Configuration configuration = mContext.getResources().getConfiguration();
     57         final int widthDp = configuration.screenWidthDp;
     58         final int heightDp = configuration.screenHeightDp;
     59         final int smallest = configuration.smallestScreenWidthDp;
     60 
     61         if (smallest > 600 || widthDp > 600 || (widthDp > 960 && heightDp > 720)
     62                 || (widthDp > 720 && heightDp > 960)) {
     63             // For values-w600dp, values-sw600dp and values-xlarge.
     64             return 5;
     65         } else if (widthDp >= 500 || (widthDp > 640 && heightDp > 480)
     66                 || (widthDp > 480 && heightDp > 640)) {
     67             // For values-w500dp and values-large.
     68             return 4;
     69         } else if (widthDp >= 360) {
     70             // For values-w360dp.
     71             return 3;
     72         } else {
     73             return 2;
     74         }
     75     }
     76 
     77     public boolean showsOverflowMenuButton() {
     78         if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
     79             return true;
     80         } else {
     81             return !ViewConfiguration.get(mContext).hasPermanentMenuKey();
     82         }
     83     }
     84 
     85     public int getEmbeddedMenuWidthLimit() {
     86         return mContext.getResources().getDisplayMetrics().widthPixels / 2;
     87     }
     88 
     89     public boolean hasEmbeddedTabs() {
     90         return mContext.getResources().getBoolean(R.bool.abc_action_bar_embed_tabs);
     91     }
     92 
     93     public int getTabContainerHeight() {
     94         TypedArray a = mContext.obtainStyledAttributes(null, R.styleable.ActionBar,
     95                 R.attr.actionBarStyle, 0);
     96         int height = a.getLayoutDimension(R.styleable.ActionBar_height, 0);
     97         Resources r = mContext.getResources();
     98         if (!hasEmbeddedTabs()) {
     99             // Stacked tabs; limit the height
    100             height = Math.min(height,
    101                     r.getDimensionPixelSize(R.dimen.abc_action_bar_stacked_max_height));
    102         }
    103         a.recycle();
    104         return height;
    105     }
    106 
    107     public boolean enableHomeButtonByDefault() {
    108         // Older apps get the home button interaction enabled by default.
    109         // Newer apps need to enable it explicitly.
    110         return mContext.getApplicationInfo().targetSdkVersion <
    111                 Build.VERSION_CODES.ICE_CREAM_SANDWICH;
    112     }
    113 
    114     public int getStackedTabMaxWidth() {
    115         return mContext.getResources().getDimensionPixelSize(
    116                 R.dimen.abc_action_bar_stacked_tab_max_width);
    117     }
    118 }
    119