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.support.v7.widget.LinearLayoutManager; 20 import android.support.v7.widget.RecyclerView; 21 import android.view.ViewGroup; 22 23 import com.example.android.supportv7.Cheeses; 24 import com.example.android.supportv7.R; 25 import com.example.android.supportv7.widget.adapter.SimpleStringAdapter; 26 import com.example.android.supportv7.widget.util.ConfigToggle; 27 28 /** 29 * A configurably janky activity that uses {@link LinearLayoutManager}. 30 */ 31 public class LinearLayoutManagerJankActivity extends LinearLayoutManagerActivity { 32 33 private boolean mBindSlowdownEnabled = true; 34 private boolean mInflateSlowdownEnabled = true; 35 36 /** 37 * Spin wait. Used instead of sleeping so a core is used up for the duration, and so 38 * traces/sampled profiling show the sections as expensive, and not just a scheduling mistake. 39 */ 40 private static void spinWaitMs(long ms) { 41 long start = System.nanoTime(); 42 while (System.nanoTime() - start < ms * 1000L * 1000L); 43 } 44 45 @Override 46 protected RecyclerView.Adapter createAdapter() { 47 return new SimpleStringAdapter(this, Cheeses.sCheeseStrings) { 48 @Override 49 public void onBindViewHolder(ViewHolder holder, int position) { 50 super.onBindViewHolder(holder, position); 51 if (mBindSlowdownEnabled) spinWaitMs(8); 52 } 53 54 @Override 55 public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) { 56 if (mInflateSlowdownEnabled) spinWaitMs(4); 57 return super.onCreateViewHolder(parent, viewType); 58 } 59 }; 60 } 61 62 @Override 63 protected ConfigToggle[] createConfigToggles() { 64 return new ConfigToggle[]{ 65 new ConfigToggle(this, R.string.enable_bind_slowdown) { 66 @Override 67 public boolean isChecked() { return mBindSlowdownEnabled; } 68 69 @Override 70 public void onChange(boolean newValue) { mBindSlowdownEnabled = newValue; } 71 }, 72 new ConfigToggle(this, R.string.enable_inflate_slowdown) { 73 @Override 74 public boolean isChecked() { return mInflateSlowdownEnabled; } 75 76 @Override 77 public void onChange(boolean newValue) { mInflateSlowdownEnabled = newValue; } 78 }, 79 new ConfigToggle(this, R.string.enable_prefetch) { 80 @Override 81 public boolean isChecked() { return mLayoutManager.isItemPrefetchEnabled(); } 82 83 @Override 84 public void onChange(boolean newValue) { 85 mLayoutManager.setItemPrefetchEnabled(newValue); 86 } 87 }, 88 }; 89 } 90 } 91