RootsOracle.java
/*
* Copyright (C) 2014 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.test.espresso.base;
import static androidx.test.internal.util.Checks.checkState;
import static kotlin.collections.CollectionsKt.emptyList;
import static kotlin.collections.CollectionsKt.toList;
import android.os.Looper;
import android.util.Log;
import android.view.View;
import android.view.WindowManager.LayoutParams;
import androidx.test.espresso.Root;
import androidx.test.platform.view.inspector.WindowInspectorCompat;
import androidx.test.platform.view.inspector.WindowInspectorCompat.ViewRetrievalException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
import javax.inject.Inject;
/**
* Provides access to all root views in an application.
*
* <p>95% of the time this is unnecessary and we can operate solely on current Activity's root view
* as indicated by getWindow().getDecorView(). However in the case of popup windows, menus, and
* dialogs the actual view hierarchy we should be operating on is in another root.
*
* <p>Obviously, you need to be on the main thread to use this.
*/
final class RootsOracle implements ActiveRootLister {
private static final String TAG = RootsOracle.class.getSimpleName();
private final Looper mainLooper;
@Inject
RootsOracle(Looper mainLooper) {
this.mainLooper = mainLooper;
}
@Override
public List<Root> listActiveRoots() {
checkState(mainLooper.equals(Looper.myLooper()), "must be called on main thread.");
try {
List<Root> roots = new ArrayList<>();
// return roots in reverse order, to match legacy behavior that assumes
// window ordering by position
for (View view : reverse(WindowInspectorCompat.getGlobalWindowViews())) {
roots.add(
new Root.Builder()
.withDecorView(view)
.withWindowLayoutParams((LayoutParams) view.getLayoutParams())
.build());
}
// return an immutable list
return toList(roots);
} catch (ViewRetrievalException e) {
Log.w(TAG, "Failed to retrieve root views", e);
return emptyList();
}
}
private List<View> reverse(List<View> globalWindowViews) {
Collections.reverse(globalWindowViews);
return globalWindowViews;
}
}