1 /* 2 * Copyright (C) 2019 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 package com.android.customization.picker; 17 18 import static androidx.core.view.ViewCompat.LAYOUT_DIRECTION_RTL; 19 20 import android.app.Activity; 21 import android.content.Context; 22 import android.view.LayoutInflater; 23 import android.view.View; 24 import android.view.ViewGroup; 25 26 import androidx.annotation.LayoutRes; 27 import androidx.annotation.NonNull; 28 import androidx.cardview.widget.CardView; 29 import androidx.core.view.ViewCompat; 30 import androidx.viewpager.widget.PagerAdapter; 31 32 import com.android.customization.picker.BasePreviewAdapter.PreviewPage; 33 import com.android.wallpaper.util.SizeCalculator; 34 import com.android.wallpaper.widget.PreviewPager; 35 36 import java.util.ArrayList; 37 import java.util.List; 38 39 /** 40 * Base adapter for {@link PreviewPager}. 41 * It can be used as-is by creating an extension of {@link PreviewPage} and adding pages via 42 * {@link #addPage(PreviewPage)} 43 * @param <T> the type of {@link PreviewPage} that this adapter will handle. 44 */ 45 public class BasePreviewAdapter<T extends PreviewPage> extends PagerAdapter { 46 47 private final int mPreviewCardResId; 48 private final Context mContext; 49 private final LayoutInflater mInflater; 50 protected final List<T> mPages = new ArrayList<>(); 51 BasePreviewAdapter(Context context, @LayoutRes int previewCardResId)52 protected BasePreviewAdapter(Context context, @LayoutRes int previewCardResId) { 53 mContext = context; 54 mPreviewCardResId = previewCardResId; 55 mInflater = LayoutInflater.from(mContext); 56 } 57 addPage(T p)58 protected void addPage(T p) { 59 mPages.add(p); 60 } 61 62 @Override getCount()63 public int getCount() { 64 return mPages.size(); 65 } 66 67 @Override isViewFromObject(@onNull View view, @NonNull Object object)68 public boolean isViewFromObject(@NonNull View view, @NonNull Object object) { 69 return view == ((PreviewPage) object).card; 70 } 71 72 @NonNull 73 @Override instantiateItem(@onNull ViewGroup container, int position)74 public Object instantiateItem(@NonNull ViewGroup container, int position) { 75 if (ViewCompat.getLayoutDirection(container) == LAYOUT_DIRECTION_RTL) { 76 position = mPages.size() - 1 - position; 77 } 78 CardView card = (CardView) mInflater.inflate(mPreviewCardResId, container, false); 79 T page = mPages.get(position); 80 81 page.setCard(card); 82 page.bindPreviewContent(); 83 if (card.getParent() != null) { 84 container.removeView(card); 85 } 86 container.addView(card); 87 return page; 88 } 89 90 @Override destroyItem(@onNull ViewGroup container, int position, @NonNull Object object)91 public void destroyItem(@NonNull ViewGroup container, int position, 92 @NonNull Object object) { 93 View card = ((PreviewPage) object).card; 94 ((PreviewPage) object).card = null; 95 if (card.getParent() == container) { 96 container.removeView(card); 97 } 98 } 99 100 /** 101 * Represents a possible page in a {@link PreviewPager}, based on a CardView container. 102 * Override {@link #bindPreviewContent()} to bind the contents of the page when instantiated. 103 */ 104 public static abstract class PreviewPage { 105 protected final String title; 106 protected CardView card; 107 108 private Activity mActivity; 109 PreviewPage(String title, Activity activity)110 protected PreviewPage(String title, Activity activity) { 111 this.title = title; 112 mActivity = activity; 113 } 114 setCard(CardView card)115 public void setCard(CardView card) { 116 card.addOnLayoutChangeListener( 117 new View.OnLayoutChangeListener() { 118 @Override 119 public void onLayoutChange(View v, int left, int top, int right, int bottom, 120 int oldLeft, int oldTop, int oldRight, int oldBottom) { 121 card.setRadius(SizeCalculator.getPreviewCornerRadius( 122 mActivity, card.getMeasuredWidth())); 123 card.removeOnLayoutChangeListener(this); 124 } 125 }); 126 this.card = card; 127 } 128 bindPreviewContent()129 public abstract void bindPreviewContent(); 130 } 131 } 132