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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 com.android.contacts.common.util;
     18 
     19 import android.content.res.Resources;
     20 import android.graphics.Outline;
     21 import android.view.View;
     22 import android.view.ViewGroup;
     23 import android.view.ViewOutlineProvider;
     24 import android.widget.ListView;
     25 
     26 import com.android.contacts.common.R;
     27 
     28 /**
     29  * Provides static functions to work with views
     30  */
     31 public class ViewUtil {
     32     private ViewUtil() {}
     33 
     34     /**
     35      * Returns the width as specified in the LayoutParams
     36      * @throws IllegalStateException Thrown if the view's width is unknown before a layout pass
     37      * s
     38      */
     39     public static int getConstantPreLayoutWidth(View view) {
     40         // We haven't been layed out yet, so get the size from the LayoutParams
     41         final ViewGroup.LayoutParams p = view.getLayoutParams();
     42         if (p.width < 0) {
     43             throw new IllegalStateException("Expecting view's width to be a constant rather " +
     44                     "than a result of the layout pass");
     45         }
     46         return p.width;
     47     }
     48 
     49     /**
     50      * Returns a boolean indicating whether or not the view's layout direction is RTL
     51      *
     52      * @param view - A valid view
     53      * @return True if the view's layout direction is RTL
     54      */
     55     public static boolean isViewLayoutRtl(View view) {
     56         return view.getLayoutDirection() == View.LAYOUT_DIRECTION_RTL;
     57     }
     58 
     59     private static final ViewOutlineProvider OVAL_OUTLINE_PROVIDER = new ViewOutlineProvider() {
     60         @Override
     61         public void getOutline(View view, Outline outline) {
     62             outline.setOval(0, 0, view.getWidth(), view.getHeight());
     63         }
     64     };
     65 
     66     private static final ViewOutlineProvider RECT_OUTLINE_PROVIDER = new ViewOutlineProvider() {
     67         @Override
     68         public void getOutline(View view, Outline outline) {
     69             outline.setRect(0, 0, view.getWidth(), view.getHeight());
     70         }
     71     };
     72 
     73     /**
     74      * Adds a rectangular outline to a view. This can be useful when you want to add a shadow
     75      * to a transparent view. See b/16856049.
     76      * @param view view that the outline is added to
     77      * @param res The resources file.
     78      */
     79     public static void addRectangularOutlineProvider(View view, Resources res) {
     80         view.setOutlineProvider(RECT_OUTLINE_PROVIDER);
     81     }
     82 
     83     /**
     84      * Configures the floating action button, clipping it to a circle and setting its translation z.
     85      * @param view The float action button's view.
     86      * @param res The resources file.
     87      */
     88     public static void setupFloatingActionButton(View view, Resources res) {
     89         view.setOutlineProvider(OVAL_OUTLINE_PROVIDER);
     90         view.setTranslationZ(
     91                 res.getDimensionPixelSize(R.dimen.floating_action_button_translation_z));
     92     }
     93 
     94     /**
     95      * Adds padding to the bottom of the given {@link ListView} so that the floating action button
     96      * does not obscure any content.
     97      *
     98      * @param listView to add the padding to
     99      * @param res valid resources object
    100      */
    101     public static void addBottomPaddingToListViewForFab(ListView listView, Resources res) {
    102         final int fabPadding = res.getDimensionPixelSize(
    103                 R.dimen.floating_action_button_list_bottom_padding);
    104         listView.setPaddingRelative(listView.getPaddingStart(), listView.getPaddingTop(),
    105                 listView.getPaddingEnd(), listView.getPaddingBottom() + fabPadding);
    106         listView.setClipToPadding(false);
    107     }
    108 }
    109