我正在掌握 Kotlin 协程并试图弄清楚
1-什么是热流和冷流?
2-它们之间的主要区别是什么?
3-什么时候使用每一个?
我是喷气背包组合的新手,并试图了解remember
和mutableStateOf
换句话说,这条线之间的尊重
val text = remember{ mutableStateOf("") }
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和这个
val text = remember{ "" }
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这也
val text = mutableStateOf("")
Run Code Online (Sandbox Code Playgroud) 我正在尝试在 android studio 版本中实现 hilt2020.1.1 Canary 1
但我在 gradle 中收到此错误
Unable to find method ''void com.android.build.api.extension.AndroidComponentsExtension$DefaultImpls.androidTests$default(com.android.build.api.extension.AndroidComponentsExtension, com.android.build.api.extension.VariantSelector, kotlin.jvm.functions.Function1, int, java.lang.Object)''
'void com.android.build.api.extension.AndroidComponentsExtension$DefaultImpls.androidTests$default(com.android.build.api.extension.AndroidComponentsExtension, com.android.build.api.extension.VariantSelector, kotlin.jvm.functions.Function1, int, java.lang.Object)'
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Run Code Online (Sandbox Code Playgroud) 我需要让用户能够使用新的Activity Result API从手机存储中仅选择文档类型(例如:pdf、docs、xls) ,但问题是当我像下面的代码一样启动合同时
private val getContent = registerForActivityResult(ActivityResultContracts.GetContent()) { uri: Uri? ->
...
}
fun pickDocument() = getContent.launch("*/*")
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用户可以选择任何文件类型,包括图像、视频……