widget

作用介绍

• 填充满父组件 - Positioned.fill(child: Image.asset('images/login-bg1.jpg',fit: BoxFit.cover)) 表格将其 child 下的 widget 调整宽高使其充满父组件，可用于充满屏幕
• 添加蒙层 - 下面代码中第二个元素使用 Positioned.fill 为前面一个元素添加蒙层

  _background() {
    return [
      Positioned.fill(child: Image.asset('images/login-bg1.jpg',fit: BoxFit.cover)),
      // 为上面一个元素添加蒙层
      Positioned.fill(child: Container(decoration: const BoxDecoration(color: Colors.black54)))
    ];
  }

布局

单子元素

Container

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Center

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Align

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FractionallySizeBox

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SizedBox

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FittedBox

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ConstrainedBox

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OverflowBox

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AspectRatio

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Offstage

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多子元素

Row

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Column

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Stack

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IndexedStack

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Flow

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Table

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Wrap

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ListBody

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文本

Text

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RichText

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可滚动的

ListView

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GridView

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NestedScrollView

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CustomScrollView

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绘制和效果

Opacity

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Transform

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ClipOval

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DecorateBox

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FractionalTranslation

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RotatedBox

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ClipPath

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ClipRect

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CustomPaint

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BackdropFilter

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图片和资产

Image

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Icon

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RawImage

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AssetBundle

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样式

Padding

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Theme

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MediaQuery

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