考虑使用 toMutableList() 函数: presenter.getContacts().toMutableList() There are toMutableList() extensions for the stdlib types that one might want to convert to a mutable list: Collection<T> , Iterable<T> , Sequence<T> , CharSequence , Array<T> 和原始数组。 原文由 hotkey 发布,翻译遵...
println(filterIndexedToList) // [2, 4, 6, 8] //如果想在集合中找到指定类型的实例元素可以使用filterIsInstance。 val mixedList = listOf(1, 2, 3, "one", "two", 4, "three", "four", 5, 6, "five", 7) val strList = mixedList.filterIsInstance<String>() val intList = mixedList....
). This operator converts any value to the non-null corresponding type. For example, a variable of type String? becomes of a value of type String. If the value to be converted is null then the operator throws an exception. 代码语言:javascript 代码运行次数:0 运行 AI代码解释 // it ...
But if you want to create a list that could be mutable, Kotlin provides MutableList<T> class to define a mutable list. In this tutorial, we shall learn with examples on how to access and modify items in a list, and how to convert it to other Collection types. Kotlin List – Initialize...
forecast.temp.min.toInt())} private fun convertDate(date: Long): String { val df = DateFormat.getDateInstance(DateFormat.MEDIUM, Locale.getDefault()) return df.format(date * 1000) } data class ForecastList(val city: String, val country: String,val dailyForecast:List<Forecast>) ...
如果我们真的想确保对象不会被修改,我们必须使用不可变引用和不可变对象。幸运的是,Kotlin 的标准库包含了任何集合接口(List与MutableList,Map与MutableMap等)的不可变等价物,对于用于创建特定集合实例的辅助函数也是如此: 类型推断 正如我们在之前的例子中看到的,与 Java 不同,Kotlin 类型是在变量名之后定义的: ...
The toList method returns an immutable ArrayList object. In case we need a mutable ArrayList, we can call the toMutableList method: inputSet.toMutableList(). 5. Conclusion In this article, we’ve learned how to convert between Set and List in Kotlin. As always, the code for these examples...
fun convertListToString(){ val nameCollection = listOf( "刘一", "陈二", "张三", "李四", "王五", "赵六", "孙七", "周八", "吴九", "郑十" ) val message = nameCollection.joinToString( separator = " ", prefix = "在古代,根据人口数量和宗族的影响力,有", ...
First, we’ll create a mutable list and add an element to it: val mutableList = mutableListOf<String>() mutableList.add("Hello") // Prints "Hello" println(mutableList.joinToString()) We can create an immutable list from our mutable list: val immutableList: List<String> = mutableList.to...
在首次进入页面时候,调用updateAllAudioList异步加载服务端音频数据,在用户点击播放时,调用onStart按需初始化播放器列表等相关数据。这样公共部分的处理就基本完成了 桌面模块 桌面这里我们使用JavaFx中media模块实现 桌面依赖引用 valos:OperatingSystem=OperatingSystem.current()valplatform=when{os.isWindows->"win"os.is...