kotlin - 喷气背包组合中给定背景错误的 'on' 颜色冲突

Question

我正在使用 jetpack compose 为我的应用程序制作一个主题，我有这个:

@Composable
fun MyTheme(content: @Composable () -> Unit) {

    val colors = lightColors(
        primary = CustomColors.Custom1,
        primaryVariant = CustomColors.Custom2,
        onPrimary = Color.White,
        background = Color.White,
        secondary = CustomColors.Custom2
        )
    MaterialTheme(colors = colors, content = content)

}

object CustomColors{

    val Custom1 = Color(0xEF119335)
    val Custom2= Color(0xAA892335)

}

问题是当我添加 secondary = CustomColors.Custom2 时, 我在 onPrimary = Color.White 中收到错误消息.错误是这样的:

Conflicting 'on' color for a given background error

Answer 1

来自 Compose 的错误描述 source code

Background colors with the same value should have the same 'on' color

In the Material color system background colors have a corresponding 'on' color which is used for the content color inside a component. For example, a button colored primary will have onPrimary text. Because of this, it is important that there is only one possible onColor for a given color value, otherwise there is no way to know which 'on' color should be used inside a component. To fix this either use the same 'on' color for identical background colors, or use a different background color for each 'on' color.

就您而言，您同时拥有 primaryVariant和 secondary设置为 CustomColors.Custom2 ，这意味着相应的背景颜色也应该相同。
默认 onSecondary颜色是 Color.Black ，并为 onPrimary您已指定 Color.White ，这就是为什么编译器不高兴。
您可以通过指定 onSecondary = Color.White 来解决此问题。或为 primaryVariant 选择不同的颜色和 secondary .
如果在这个解释之后你仍然想使用这些确切的颜色，你可以用 @SuppressLint("ConflictingOnColor") 忽略这个警告。 :但某些系统或 Material 元素可能看起来不太好。