1 /* 2 * Copyright (C) 2016 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.example.android.supportv7.widget; 18 19 import android.view.ViewGroup; 20 21 import androidx.recyclerview.widget.LinearLayoutManager; 22 import androidx.recyclerview.widget.RecyclerView; 23 24 import com.example.android.supportv7.Cheeses; 25 import com.example.android.supportv7.R; 26 import com.example.android.supportv7.widget.adapter.SimpleStringAdapter; 27 import com.example.android.supportv7.widget.util.ConfigToggle; 28 29 /** 30 * A configurably janky activity that uses {@link LinearLayoutManager}. 31 */ 32 public class LinearLayoutManagerJankActivity extends LinearLayoutManagerActivity { 33 34 private boolean mBindSlowdownEnabled = true; 35 private boolean mInflateSlowdownEnabled = true; 36 37 /** 38 * Spin wait. Used instead of sleeping so a core is used up for the duration, and so 39 * traces/sampled profiling show the sections as expensive, and not just a scheduling mistake. 40 */ 41 private static void spinWaitMs(long ms) { 42 long start = System.nanoTime(); 43 while (System.nanoTime() - start < ms * 1000L * 1000L); 44 } 45 46 @Override 47 protected RecyclerView.Adapter createAdapter() { 48 return new SimpleStringAdapter(this, Cheeses.sCheeseStrings) { 49 @Override 50 public void onBindViewHolder(ViewHolder holder, int position) { 51 super.onBindViewHolder(holder, position); 52 if (mBindSlowdownEnabled) spinWaitMs(8); 53 } 54 55 @Override 56 public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 57 if (mInflateSlowdownEnabled) spinWaitMs(4); 58 return super.onCreateViewHolder(parent, viewType); 59 } 60 }; 61 } 62 63 @Override 64 protected ConfigToggle[] createConfigToggles() { 65 return new ConfigToggle[]{ 66 new ConfigToggle(this, R.string.enable_bind_slowdown) { 67 @Override 68 public boolean isChecked() { return mBindSlowdownEnabled; } 69 70 @Override 71 public void onChange(boolean newValue) { mBindSlowdownEnabled = newValue; } 72 }, 73 new ConfigToggle(this, R.string.enable_inflate_slowdown) { 74 @Override 75 public boolean isChecked() { return mInflateSlowdownEnabled; } 76 77 @Override 78 public void onChange(boolean newValue) { mInflateSlowdownEnabled = newValue; } 79 }, 80 new ConfigToggle(this, R.string.enable_prefetch) { 81 @Override 82 public boolean isChecked() { return mLayoutManager.isItemPrefetchEnabled(); } 83 84 @Override 85 public void onChange(boolean newValue) { 86 mLayoutManager.setItemPrefetchEnabled(newValue); 87 } 88 }, 89 }; 90 } 91 } 92
