semantics_and_children_test.dart 2.51 KB
Newer Older
Ian Hickson's avatar
Ian Hickson committed
1
// Copyright 2014 The Flutter Authors. All rights reserved.
Ian Hickson's avatar
Ian Hickson committed
2 3 4
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

5 6
// @dart = 2.8

Ian Hickson's avatar
Ian Hickson committed
7 8
import 'package:flutter/material.dart';
import 'package:flutter/rendering.dart';
9
import 'package:flutter_test/flutter_test.dart' show TestVSync;
10
import '../flutter_test_alternative.dart';
Ian Hickson's avatar
Ian Hickson committed
11

12 13
import 'rendering_tester.dart';

Ian Hickson's avatar
Ian Hickson committed
14 15 16 17 18 19 20
int countSemanticsChildren(RenderObject object) {
  int count = 0;
  object.visitChildrenForSemantics((RenderObject child) {
    count += 1;
  });
  return count;
}
21

Ian Hickson's avatar
Ian Hickson committed
22 23
void main() {
  test('RenderOpacity and children and semantics', () {
24 25
    final RenderOpacity box = RenderOpacity(
      child: RenderParagraph(
Ian Hickson's avatar
Ian Hickson committed
26 27 28 29
        const TextSpan(),
        textDirection: TextDirection.ltr,
      ),
    );
Ian Hickson's avatar
Ian Hickson committed
30 31 32 33 34 35 36 37 38 39 40 41 42 43
    expect(countSemanticsChildren(box), 1);
    box.opacity = 0.5;
    expect(countSemanticsChildren(box), 1);
    box.opacity = 0.25;
    expect(countSemanticsChildren(box), 1);
    box.opacity = 0.125;
    expect(countSemanticsChildren(box), 1);
    box.opacity = 0.0;
    expect(countSemanticsChildren(box), 0);
    box.opacity = 0.125;
    expect(countSemanticsChildren(box), 1);
    box.opacity = 0.0;
    expect(countSemanticsChildren(box), 0);
  });
44 45

  test('RenderOpacity and children and semantics', () {
46 47
    final AnimationController controller = AnimationController(vsync: const TestVSync());
    final RenderAnimatedOpacity box = RenderAnimatedOpacity(
48
      alwaysIncludeSemantics: false,
49
      opacity: controller,
50
      child: RenderParagraph(
51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76
        const TextSpan(),
        textDirection: TextDirection.ltr,
      ),
    );
    expect(countSemanticsChildren(box), 0); // controller defaults to 0.0
    controller.value = 0.2; // has no effect, box isn't subscribed yet
    expect(countSemanticsChildren(box), 0);
    controller.value = 1.0; // ditto
    expect(countSemanticsChildren(box), 0); // alpha is still 0
    layout(box); // this causes the box to attach, which makes it subscribe
    expect(countSemanticsChildren(box), 1);
    controller.value = 1.0;
    expect(countSemanticsChildren(box), 1);
    controller.value = 0.5;
    expect(countSemanticsChildren(box), 1);
    controller.value = 0.25;
    expect(countSemanticsChildren(box), 1);
    controller.value = 0.125;
    expect(countSemanticsChildren(box), 1);
    controller.value = 0.0;
    expect(countSemanticsChildren(box), 0);
    controller.value = 0.125;
    expect(countSemanticsChildren(box), 1);
    controller.value = 0.0;
    expect(countSemanticsChildren(box), 0);
  });
Ian Hickson's avatar
Ian Hickson committed
77
}