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
17package com.example.android.supportv7.widget;
18
19import android.view.ViewGroup;
20
21import androidx.recyclerview.widget.LinearLayoutManager;
22import androidx.recyclerview.widget.RecyclerView;
23
24import com.example.android.supportv7.Cheeses;
25import com.example.android.supportv7.R;
26import com.example.android.supportv7.widget.adapter.SimpleStringAdapter;
27import com.example.android.supportv7.widget.util.ConfigToggle;
28
29/**
30 * A configurably janky activity that uses {@link LinearLayoutManager}.
31 */
32public 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