Flutter测试时如何找到Stack的顺序？

Question

假设我有一堆不一样的小部件：

return Stack(
  children: <Widget>[
    Container(),
    Text('Hey'),
    Positioned(top: 300.0, child: CustomWidget()),
  ],
);

如何测试子部件的顺序？我可以为每个项目分配键，但如何判断哪个项目出现在另一个项目的前面？

我可以为我的 Stack 分配一个键，将每个子项包装在 中Positioned，然后使用find.byKey(stackKey)来获取我的 Stack，然后使用find.byType(Positioned)来获取它的子项。这会返回一个Iterable我可以转换为a的List. 但是，能find.byType()保证每次返回相同的订单吗？

Answer 1

我在这里所做的是将键添加到堆栈上的子项中，并包含预期顺序的编号。

\n

Stack(\n  children: [\n    Container(\n      key: Key(\'StackChildKey1\'),\n    ),\n    Container(\n      key: Key(\'StackChildKey2\'),\n    ),\n    Container(\n      key: Key(\'StackChildKey3\'),\n    ),\n  ],\n),\n

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在测试脚本上，将所有匹配的键添加到我们稍后可以检查的列表中。

\n

List<String> widgetOrderList = [];\ntester.allWidgets.forEach((Widget element) {\n  /// Only add the Widget Key with the expected tag \'StackChildKey\'\n  if (element.key.toString().contains(\'StackChildKey\')) {\n    widgetOrderList.add(element.key.toString());\n  }\n});\n

\n

用于String.compareTo(String)验证小部件的顺序。

\n

// This List<int> contains String.compareTo(String) results\n/// https://api.flutter.dev/flutter/dart-core/String/compareTo.html\n/// 0 \xe2\x88\x92 when the Strings are equal.\n/// 1 \xe2\x88\x92 when the first String is greater than the second\n/// -1 \xe2\x88\x92 when the first String is smaller than the second\nList<int> sortCheck= [];\nfor (int i = 0; i < widgetOrderList.length; i++) {\n  /// Compare current Widget Key with next while still within bounds\n  if (i + 1 < widgetOrderList.length) {\n    sortCheck.add(widgetOrderList[i].compareTo(widgetOrderList[i+1]));\n  }\n}\n

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然后用于expect添加测试用例。这期望结果为isWidgetStackSorted真。

\n

/// Flutter test expects that the [isWidgetStackSorted] to be true\n/// if List<int> sortCheck contains either 0 or 1, this indicates\n/// that a pair isn\'t in the correct order on Stack\nvar isWidgetStackSorted = !(sortCheck.contains(0) || sortCheck.contains(1));\nexpect(isWidgetStackSorted, true);\n

\n

完成测试。

\n

/// Flutter test expects that the [isWidgetStackSorted] to be true\n/// if List<int> sortCheck contains either 0 or 1, this indicates\n/// that a pair isn\'t in the correct order on Stack\nvar isWidgetStackSorted = !(sortCheck.contains(0) || sortCheck.contains(1));\nexpect(isWidgetStackSorted, true);\n

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