如何在flutter中使用暗模式和不同分辨率的资源图像?

Sza*_*mot 5 assets image flutter ios-darkmode android-dark-theme

我在我的 flutter 项目中使用具有不同分辨率的图像,如此处所述。现在我想为深色模式主题添加自定义图像。我在 pubspec.yaml 中的资产声明如下所示:

flutter:
  uses-material-design: true
  assets:
    - assets/images/img_menu.png
    - ...
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我的资产结构:

  .../pubspec.yaml
  .../assets/images/img_menu.png
  .../assets/images/0.75x/img_menu.png
  .../assets/images/1.5x/img_menu.png
  .../assets/images/2.0x/img_menu.png
  .../assets/images/3.0x/img_menu.png
  .../assets/images/4.0x/img_menu.png
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我以这种方式在项目中加载图像:

Image.asset('assets/images/img_menu.png')
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我知道对于简单的单色图像我可以像这样改变它的颜色:

Image.asset('assets/images/img_menu.png', 
                      color: Theme.of(context).brightness == Brightness.light
                      ? Colors.black
                      : Colors.white,)
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但我的大多数图像都比较复杂,所以我必须为它们加载自定义资源。

正如此处所述,在添加暗模式资产后,我可以不做任何更改地保留 pubspec。我尝试过黑暗模式的不同资产结构,但没有一个有效。

1:

  .../pubspec.yaml
  .../assets/images/img_menu.png
  .../assets/images/dark/img_menu.png
  .../assets/images/0.75x/img_menu.png
  .../assets/images/0.75x/dark/img_menu.png
  .../assets/images/1.5x/img_menu.png
  .../assets/images/1.5x/dark/img_menu.png
  .../assets/images/2.0x/img_menu.png
  .../assets/images/2.0x/dark/img_menu.png
  .../assets/images/3.0x/img_menu.png
  .../assets/images/3.0x/dark/img_menu.png
  .../assets/images/4.0x/img_menu.png
  .../assets/images/4.0x/dark/img_menu.png
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2:

  .../pubspec.yaml
  .../assets/images/img_menu.png
  .../assets/images/0.75x/img_menu.png
  .../assets/images/1.5x/img_menu.png
  .../assets/images/2.0x/img_menu.png
  .../assets/images/3.0x/img_menu.png
  .../assets/images/4.0x/img_menu.png
  .../assets/images/dark/img_menu.png
  .../assets/images/dark/0.75x/img_menu.png
  .../assets/images/dark/1.5x/img_menu.png
  .../assets/images/dark/2.0x/img_menu.png
  .../assets/images/dark/3.0x/img_menu.png
  .../assets/images/dark/4.0x/img_menu.png
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3:

  .../pubspec.yaml
  .../assets/images/img_menu.png
  .../assets/images/0.75x/img_menu.png
  .../assets/images/1.5x/img_menu.png
  .../assets/images/2.0x/img_menu.png
  .../assets/images/3.0x/img_menu.png
  .../assets/images/4.0x/img_menu.png
  .../assets/dark/images/img_menu.png
  .../assets/dark/images/0.75x/img_menu.png
  .../assets/dark/images/1.5x/img_menu.png
  .../assets/dark/images/2.0x/img_menu.png
  .../assets/dark/images/3.0x/img_menu.png
  .../assets/dark/images/4.0x/img_menu.png
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单图像的解决方案是这样加载它:

Image.asset(Theme.of(context).brightness == Brightness.light 
                      ? 'assets/images/img_menu.png'
                      : 'assets/images/dark/img_menu.png',)
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但这对于整个项目来说并不是一个方便的解决方案。

更奇怪的是,在 2 种变体应用程序中,加载了两种颜色的深色图像:浅色和深色主题(在 iPhone 和 Android 上测试)。

所以问题是:暗模式和分辨率感知图像资源的文件结构应该是什么样的?

小智 2

到目前为止,目前唯一支持的变体是缩放(设备像素比),而不是黑暗模式。

请参阅: https: //github.com/flutter/flutter/issues/44482