1 /* 2 * Copyright (C) 2017 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.car.media.drawer; 17 18 import com.android.car.app.CarDrawerActivity; 19 import com.android.car.app.CarDrawerAdapter; 20 import com.android.car.app.DrawerItemViewHolder; 21 22 /** 23 * Subclass of CarDrawerAdapter used by the Media app. 24 * <p> 25 * This adapter delegates actual fetching of items (and other operations) to a 26 * {@link MediaItemsFetcher}. The current fetcher being used can be updated at runtime. 27 */ 28 class MediaDrawerAdapter extends CarDrawerAdapter { 29 private final CarDrawerActivity mActivity; 30 private MediaItemsFetcher mCurrentFetcher; 31 MediaDrawerAdapter(CarDrawerActivity activity, boolean useSmallLayout)32 MediaDrawerAdapter(CarDrawerActivity activity, boolean useSmallLayout) { 33 super(activity, true /* showDisabledListOnEmpty */, useSmallLayout); 34 mActivity = activity; 35 } 36 37 /** 38 * Switch the {@link MediaItemsFetcher} being used to fetch items. The new fetcher is kicked-off 39 * and the drawer's content's will be updated to show newly loaded items. Any old fetcher is 40 * cleaned up and released. 41 * 42 * @param fetcher New {@link MediaItemsFetcher} to use for display Drawer items. 43 */ setFetcher(MediaItemsFetcher fetcher)44 void setFetcher(MediaItemsFetcher fetcher) { 45 if (mCurrentFetcher != null) { 46 mCurrentFetcher.cleanup(); 47 } 48 mCurrentFetcher = fetcher; 49 mCurrentFetcher.start(() -> { 50 mActivity.showLoadingProgressBar(false); 51 notifyDataSetChanged(); 52 }); 53 // Initially there will be no items and we don't want to show empty-list indicator briefly 54 // until items are fetched. 55 mActivity.showLoadingProgressBar(true); 56 } 57 58 @Override getActualItemCount()59 protected int getActualItemCount() { 60 return mCurrentFetcher != null ? mCurrentFetcher.getItemCount() : 0; 61 } 62 63 @Override populateViewHolder(DrawerItemViewHolder holder, int position)64 protected void populateViewHolder(DrawerItemViewHolder holder, int position) { 65 if (mCurrentFetcher != null) { 66 mCurrentFetcher.populateViewHolder(holder, position); 67 } 68 } 69 70 @Override onItemClick(int position)71 public void onItemClick(int position) { 72 if (mCurrentFetcher != null) { 73 mCurrentFetcher.onItemClick(position); 74 } 75 } 76 } 77