packages/flutter/test/widgets/platform_view_test.dart

// Copyright 2018 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'dart:async';
import 'dart:typed_data';

import 'package:flutter/gestures.dart';
import 'package:flutter/rendering.dart';
import 'package:flutter/services.dart';
import 'package:flutter/widgets.dart';
import 'package:flutter_test/flutter_test.dart';

import '../services/fake_platform_views.dart';

void main() {

  testWidgets('Create Android view', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'webview', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Create Android view with params', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(
            viewType: 'webview',
            layoutDirection: TextDirection.ltr,
            creationParams: 'creation parameters',
            creationParamsCodec: const StringCodec(),
          ),
        ),
      ),
    );

    final FakePlatformView fakeView = viewsController.views.first;
    final Uint8List rawCreationParams = fakeView.creationParams;
    final ByteData byteData = ByteData.view(
        rawCreationParams.buffer,
        rawCreationParams.offsetInBytes,
        rawCreationParams.lengthInBytes
    );
    final dynamic actualParams = const StringCodec().decodeMessage(byteData);

    expect(actualParams, 'creation parameters');
    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'webview', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr, fakeView.creationParams)
      ]),
    );
  });

  testWidgets('Zero sized Android view is not created', (WidgetTester tester) async {
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 0.0,
          height: 0.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    expect(
      viewsController.views,
      isEmpty,
    );
  });

  testWidgets('Resize Android view', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    viewsController.resizeCompleter = Completer<void>();

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 100.0,
          height: 50.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    final Layer textureParentLayer = tester.layers[tester.layers.length - 2];
    expect(textureParentLayer, isInstanceOf<ClipRectLayer>());
    final ClipRectLayer clipRect = textureParentLayer;
    expect(clipRect.clipRect, Rect.fromLTWH(0.0, 0.0, 100.0, 50.0));
    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'webview', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );

    viewsController.resizeCompleter.complete();
    await tester.pump();

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'webview', const Size(100.0, 50.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Change Android view type', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    viewsController.registerViewType('maps');
    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'maps', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 2, 'maps', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Dispose Android view', (WidgetTester tester) async {
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    await tester.pumpWidget(
      const Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
        ),
      ),
    );

    expect(
      viewsController.views,
      isEmpty,
    );
  });

  testWidgets('Android view survives widget tree change', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    final GlobalKey key = GlobalKey();
    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr, key: key),
        ),
      ),
    );

    await tester.pumpWidget(
      Center(
        child: Container(
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr, key: key),
          ),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'webview', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Android view gets touch events', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr,),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.up();

    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
        const FakeMotionEvent(AndroidViewController.kActionUp, <int> [0], <Offset> [Offset(50.0, 50.0)]),
      ]),
    );
  });

  testWidgets('Android view transparent hit test behavior', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    int numPointerDownsOnParent = 0;
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Stack(
          children: <Widget> [
            Listener(
              behavior: HitTestBehavior.opaque,
              onPointerDown: (PointerDownEvent e) { numPointerDownsOnParent++; },
            ),
            Positioned(
              child: SizedBox(
                width: 200.0,
                height: 100.0,
                child: AndroidView(
                  viewType: 'webview',
                  hitTestBehavior: PlatformViewHitTestBehavior.transparent,
                  layoutDirection: TextDirection.ltr,
                ),
              ),
            ),
          ],
        ),
      ),
    );

    await tester.startGesture(const Offset(50.0, 50.0));

    expect(
      viewsController.motionEvents[currentViewId + 1],
      isNull,
    );
    expect(
        numPointerDownsOnParent,
        1
    );
  });

  testWidgets('Android view translucent hit test behavior', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    int numPointerDownsOnParent = 0;
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Stack(
          children: <Widget> [
            Listener(
              behavior: HitTestBehavior.opaque,
              onPointerDown: (PointerDownEvent e) { numPointerDownsOnParent++; },
            ),
            Positioned(
              child: SizedBox(
                width: 200.0,
                height: 100.0,
                child: AndroidView(
                  viewType: 'webview',
                  hitTestBehavior: PlatformViewHitTestBehavior.translucent,
                  layoutDirection: TextDirection.ltr,
                ),
              ),
            ),
          ],
        ),
      ),
    );

    await tester.startGesture(const Offset(50.0, 50.0));

    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
      ]),
    );
    expect(
        numPointerDownsOnParent,
        1
    );
  });

  testWidgets('Android view opaque hit test behavior', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');

    int numPointerDownsOnParent = 0;
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Stack(
          children: <Widget> [
            Listener(
              behavior: HitTestBehavior.opaque,
              onPointerDown: (PointerDownEvent e) { numPointerDownsOnParent++; },
            ),
            Positioned(
              child: SizedBox(
                width: 200.0,
                height: 100.0,
                child: AndroidView(
                  viewType: 'webview',
                  hitTestBehavior: PlatformViewHitTestBehavior.opaque,
                  layoutDirection: TextDirection.ltr,
                ),
              ),
            ),
          ],
        ),
      ),
    );

    await tester.startGesture(const Offset(50.0, 50.0));

    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
      ]),
    );
    expect(
        numPointerDownsOnParent,
        0
    );
  });

  testWidgets('Android view touch events are in virtual display\'s coordinate system', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: Container(
          margin: const EdgeInsets.all(10.0),
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.up();

    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(40.0, 40.0)]),
        const FakeMotionEvent(AndroidViewController.kActionUp, <int> [0], <Offset> [Offset(40.0, 40.0)]),
      ]),
    );
  });

  testWidgets('Android view directionality', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('maps');
    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'maps', layoutDirection: TextDirection.rtl),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'maps', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionRtl)
      ]),
    );

    await tester.pumpWidget(
      Center(
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(viewType: 'maps', layoutDirection: TextDirection.ltr),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'maps', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Android view ambient directionality', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('maps');
    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.rtl,
        child: Center(
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(viewType: 'maps'),
          ),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'maps', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionRtl)
      ]),
    );

    await tester.pumpWidget(
      Directionality(
        textDirection: TextDirection.ltr,
        child: Center(
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(viewType: 'maps'),
          ),
        ),
      ),
    );

    expect(
      viewsController.views,
      unorderedEquals(<FakePlatformView>[
        FakePlatformView(currentViewId + 1, 'maps', const Size(200.0, 100.0), AndroidViewController.kAndroidLayoutDirectionLtr)
      ]),
    );
  });

  testWidgets('Android view can lose gesture arenas', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    bool verticalDragAcceptedByParent = false;
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: Container(
          margin: const EdgeInsets.all(10.0),
          child: GestureDetector(
            onVerticalDragStart: (DragStartDetails d) { verticalDragAcceptedByParent = true; },
            child: SizedBox(
              width: 200.0,
              height: 100.0,
              child: AndroidView(viewType: 'webview', layoutDirection: TextDirection.ltr),
            ),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.moveBy(const Offset(0.0, 100.0));
    await gesture.up();

    expect(verticalDragAcceptedByParent, true);
    expect(
      viewsController.motionEvents[currentViewId + 1],
      isNull,
    );
  });

  testWidgets('Android view gesture recognizers', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    bool verticalDragAcceptedByParent = false;
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: GestureDetector(
          onVerticalDragStart: (DragStartDetails d) { verticalDragAcceptedByParent = true; },
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(
              viewType: 'webview',
              gestureRecognizers: <OneSequenceGestureRecognizer> [VerticalDragGestureRecognizer()],
              layoutDirection: TextDirection.ltr,
            ),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.moveBy(const Offset(0.0, 100.0));
    await gesture.up();

    expect(verticalDragAcceptedByParent, false);
    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
        const FakeMotionEvent(AndroidViewController.kActionMove, <int> [0], <Offset> [Offset(50.0, 150.0)]),
        const FakeMotionEvent(AndroidViewController.kActionUp, <int> [0], <Offset> [Offset(50.0, 150.0)]),
      ]),
    );
  });

  testWidgets('Android view can claim gesture after all pointers are up', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    bool verticalDragAcceptedByParent = false;
    // The long press recognizer rejects the gesture after the AndroidView gets the pointer up event.
    // This test makes sure that the Android view can win the gesture after it got the pointer up event.
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: GestureDetector(
          onVerticalDragStart: (DragStartDetails d) { verticalDragAcceptedByParent = true; },
          onLongPress: () {},
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(
              viewType: 'webview',
              layoutDirection: TextDirection.ltr,
            ),
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.up();

    expect(verticalDragAcceptedByParent, false);
    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
        const FakeMotionEvent(AndroidViewController.kActionUp, <int> [0], <Offset> [Offset(50.0, 50.0)]),
      ]),
    );
  });

  testWidgets('Android view rebuilt during gesture', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(
            viewType: 'webview',
            layoutDirection: TextDirection.ltr,
          ),
        ),
      ),
    );

    final TestGesture gesture = await tester.startGesture(const Offset(50.0, 50.0));
    await gesture.moveBy(const Offset(0.0, 100.0));

    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: SizedBox(
          width: 200.0,
          height: 100.0,
          child: AndroidView(
            viewType: 'webview',
            layoutDirection: TextDirection.ltr,
          ),
        ),
      ),
    );

    await gesture.up();

    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
        const FakeMotionEvent(AndroidViewController.kActionMove, <int> [0], <Offset> [Offset(50.0, 150.0)]),
        const FakeMotionEvent(AndroidViewController.kActionUp, <int> [0], <Offset> [Offset(50.0, 150.0)]),
      ]),
    );
  });

  testWidgets('Android view with eager gesture recognizer', (WidgetTester tester) async {
    final int currentViewId = platformViewsRegistry.getNextPlatformViewId();
    final FakePlatformViewsController viewsController = FakePlatformViewsController(TargetPlatform.android);
    viewsController.registerViewType('webview');
    await tester.pumpWidget(
      Align(
        alignment: Alignment.topLeft,
        child: GestureDetector(
          onVerticalDragStart: (DragStartDetails d) {},
          child: SizedBox(
            width: 200.0,
            height: 100.0,
            child: AndroidView(
              viewType: 'webview',
              gestureRecognizers: <OneSequenceGestureRecognizer>[ EagerGestureRecognizer() ],
              layoutDirection: TextDirection.ltr,
            ),
          ),
        ),
      ),
    );

    await tester.startGesture(const Offset(50.0, 50.0));

    // Normally (without the eager gesture recognizer) after just the pointer down event
    // no gesture arena member will claim the arena (so no motion events will be dispatched to
    // the Android view). Here we assert that with the eager recognizer in the gesture team the
    // pointer down event is immediately dispatched.
    expect(
      viewsController.motionEvents[currentViewId + 1],
      orderedEquals(<FakeMotionEvent> [
        const FakeMotionEvent(AndroidViewController.kActionDown, <int> [0], <Offset> [Offset(50.0, 50.0)]),
      ]),
    );
  });
}