/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.gridlayout.widget;

import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.MatcherAssert.assertThat;

import android.content.Context;
import android.util.AttributeSet;
import android.widget.FrameLayout;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

public class TestContentView extends FrameLayout {

    private CountDownLatch mLayoutCountDownLatch;

    public TestContentView(@NonNull Context context) {
        super(context);
    }

    public TestContentView(@NonNull Context context,
            @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public TestContentView(@NonNull Context context, @Nullable AttributeSet attrs,
            int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @SuppressWarnings("unused")
    public TestContentView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr,
            int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public void expectLayouts(int count) {
        mLayoutCountDownLatch = new CountDownLatch(count);
    }

    @SuppressWarnings("SameParameterValue")
    public void awaitLayouts(int seconds) throws InterruptedException {
        assertThat(mLayoutCountDownLatch.await(seconds, TimeUnit.SECONDS), equalTo(true));
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        if (mLayoutCountDownLatch != null) {
            mLayoutCountDownLatch.countDown();
        }
    }
}

/*
 * Copyright 2018 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package androidx.gridlayout.widget;

import static org.hamcrest.CoreMatchers.equalTo;
import static org.hamcrest.MatcherAssert.assertThat;

import android.content.Context;
import android.os.Build;
import android.util.AttributeSet;
import android.widget.FrameLayout;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.annotation.RequiresApi;

import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;

public class TestContentView extends FrameLayout {

    private CountDownLatch mLayoutCountDownLatch;

    public TestContentView(@NonNull Context context) {
        super(context);
    }

    public TestContentView(@NonNull Context context,
            @Nullable AttributeSet attrs) {
        super(context, attrs);
    }

    public TestContentView(@NonNull Context context, @Nullable AttributeSet attrs,
            int defStyleAttr) {
        super(context, attrs, defStyleAttr);
    }

    @RequiresApi(api = Build.VERSION_CODES.LOLLIPOP)
    @SuppressWarnings("unused")
    public TestContentView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr,
            int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
    }

    public void expectLayouts(int count) {
        mLayoutCountDownLatch = new CountDownLatch(count);
    }

    @SuppressWarnings("SameParameterValue")
    public void awaitLayouts(int seconds) throws InterruptedException {
        assertThat(mLayoutCountDownLatch.await(seconds, TimeUnit.SECONDS), equalTo(true));
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);
        if (mLayoutCountDownLatch != null) {
            mLayoutCountDownLatch.countDown();
        }
    }
}

Add RequiresApi annotation to TestContentView constructor