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 android.support.v7.widget;
18
19import static android.view.View.MeasureSpec.AT_MOST;
20import static android.view.View.MeasureSpec.EXACTLY;
21import static android.view.View.MeasureSpec.makeMeasureSpec;
22
23import static org.hamcrest.CoreMatchers.is;
24import static org.hamcrest.CoreMatchers.notNullValue;
25import static org.hamcrest.MatcherAssert.assertThat;
26
27import android.graphics.Rect;
28import android.test.suitebuilder.annotation.MediumTest;
29import android.view.View;
30
31import org.junit.Test;
32import org.junit.runner.RunWith;
33import org.junit.runners.Parameterized;
34
35import java.util.ArrayList;
36import java.util.HashMap;
37import java.util.List;
38import java.util.Map;
39
40/**
41 * Tests whether the layout manager can keep its children positions properly after it is re-laid
42 * out with larger/smaller intermediate size but the same final size.
43 */
44@MediumTest
45@RunWith(Parameterized.class)
46public class TestResizingRelayoutWithAutoMeasure extends BaseRecyclerViewInstrumentationTest {
47    private final RecyclerView.LayoutManager mLayoutManager;
48    private final float mWidthMultiplier;
49    private final float mHeightMultiplier;
50
51    public TestResizingRelayoutWithAutoMeasure(@SuppressWarnings("UnusedParameters") String name,
52            RecyclerView.LayoutManager layoutManager, float widthMultiplier,
53            float heightMultiplier) {
54        mLayoutManager = layoutManager;
55        mWidthMultiplier = widthMultiplier;
56        mHeightMultiplier = heightMultiplier;
57    }
58
59    @Parameterized.Parameters(name = "{0} w:{2} h:{3}")
60    public static List<Object[]> getParams() {
61        List<Object[]> params = new ArrayList<>();
62        for (float w : new float[]{.5f, 1f, 2f}) {
63            for (float h : new float[]{.5f, 1f, 2f}) {
64                params.add(
65                        new Object[]{"linear layout", new LinearLayoutManager(null), w, h}
66                );
67                params.add(
68                        new Object[]{"grid layout", new GridLayoutManager(null, 3), w, h}
69                );
70                params.add(
71                        new Object[]{"staggered", new StaggeredGridLayoutManager(3,
72                                StaggeredGridLayoutManager.VERTICAL), w, h}
73                );
74            }
75        }
76        return params;
77    }
78
79    @Test
80    public void testResizeDuringMeasurements() throws Throwable {
81        final RecyclerView recyclerView = new RecyclerView(getActivity());
82        recyclerView.setLayoutManager(mLayoutManager);
83        recyclerView.setAdapter(new TestAdapter(500));
84        setRecyclerView(recyclerView);
85        getInstrumentation().waitForIdleSync();
86        assertThat("Test sanity", recyclerView.getChildCount() > 0, is(true));
87        final int lastPosition = recyclerView.getAdapter().getItemCount() - 1;
88        smoothScrollToPosition(lastPosition);
89        assertThat("test sanity", recyclerView.findViewHolderForAdapterPosition(lastPosition),
90                notNullValue());
91        runTestOnUiThread(new Runnable() {
92            @Override
93            public void run() {
94                int startHeight = recyclerView.getMeasuredHeight();
95                int startWidth = recyclerView.getMeasuredWidth();
96                Map<Integer, Rect> startPositions = capturePositions(recyclerView);
97                recyclerView.measure(
98                        makeMeasureSpec((int) (startWidth * mWidthMultiplier),
99                                mWidthMultiplier == 1f ? EXACTLY : AT_MOST),
100                        makeMeasureSpec((int) (startHeight * mHeightMultiplier),
101                                mHeightMultiplier == 1f ? EXACTLY : AT_MOST));
102
103                recyclerView.measure(
104                        makeMeasureSpec(startWidth, EXACTLY),
105                        makeMeasureSpec(startHeight, EXACTLY));
106                recyclerView.dispatchLayout();
107                Map<Integer, Rect> endPositions = capturePositions(recyclerView);
108                assertStartItemPositions(startPositions, endPositions);
109            }
110        });
111    }
112
113    private void assertStartItemPositions(Map<Integer, Rect> startPositions,
114            Map<Integer, Rect> endPositions) {
115        for (Map.Entry<Integer, Rect> entry : startPositions.entrySet()) {
116            Rect rect = endPositions.get(entry.getKey());
117            assertThat("view for position " + entry.getKey() + " at" + entry.getValue(), rect,
118                    notNullValue());
119            assertThat("rect for position " + entry.getKey(), entry.getValue(), is(rect));
120        }
121    }
122
123    private Map<Integer, Rect> capturePositions(RecyclerView recyclerView) {
124        Map<Integer, Rect> positions = new HashMap<>();
125        for (int i = 0; i < mLayoutManager.getChildCount(); i++) {
126            View view = mLayoutManager.getChildAt(i);
127            int childAdapterPosition = recyclerView.getChildAdapterPosition(view);
128            Rect outRect = new Rect();
129            mLayoutManager.getDecoratedBoundsWithMargins(view, outRect);
130            // only record if outRect is visible
131            if (outRect.left >= mRecyclerView.getWidth() ||
132                    outRect.top >= mRecyclerView.getHeight() ||
133                    outRect.right < 0 ||
134                    outRect.bottom < 0) {
135                continue;
136            }
137            positions.put(childAdapterPosition, outRect);
138        }
139        return positions;
140    }
141}