它的效果也和扩展方法一样,在 扩展 lambda 作用域内,你可以以对象作为this来操作这个对象。 最后一个contract 契约,指的是代码和 Kotlin 编译器的契约。举一个例子,我们对局部变量增加了如果为空则 return 的逻辑,Kotlin 编译器便可以智能的识别出 return 之后的局部变量一定不为空,局部变量的类型会退化为非空类...
这篇文章旨在对Kotlin中的作用域方法(Scope Function)——即run、with、also、apply、let五个方法进行学习和记录(还要两个额外的方法takeIf和takeUnless),以便自己复习和让其他人学习。全文分为两个部分:官方文档翻译和作者思考。 话不多说,入正题! 官方文档翻译 (PS:这里的翻译是纯人工翻译,并且不进行直译,而是在...
android 协同程序-单元测试视图ModelScope.启动方法正如其他人提到的，runblocking只会阻止在它的作用域中启...
(JVM), Android, JavaScript, and Nativ. It is also a free and open-source language having both object-oriented and functional constructs. Since Kotlin supports function types, higher- functions along with lambdas, it is considered the best choice for programming. The major focus of Kotlin is ...
Side-effect is anything happening out of the scope of a composable function which eventually affects the composable function, it could be some state changes or anything happening on UI like user actions which has an effect on Composable. Both APIs are built to handle that effect in a controlled...
*/@kotlin.internal.InlineOnlypublicinlinefun<T,R>T.let(block:(T)->R):R{contract{callsInPlace(block,InvocationKind.EXACTLY_ONCE)}returnblock(this)} Inline Function 可以看到这5个方法全是Inline Function。这也可以理解,因为这几个方法编译后,对应 Java 代码都会产生 Function 对象,存在多余的对象创建等...
For all the cases when we don’t need thread blocking, we can use coroutineScope. Similarly to runBlocking, it will wait for its children to complete. But unlike runBlocking, this scope doesn’t block the current thread but only suspends it because coroutineScope is a suspending function. Con...
The right scope for objects and View Models in AndroidCompose. Resaca provides a simple way tokeep a Jetpack ViewModel(or any other object)in memory during the lifecycle of a@Composablefunctionand automatically clean it up when not needed anymore. This means, it retains your object or ViewModel...
In some extreme cases, accidental use of the wrong scope or extension function can even lead to error, during compilation or in runtime. The “same” extension function may have different behavior, in this case in compile time Enough theory, let’s check some production code!
Senior Android Engineer Follow mdp3030 Jan 30, 2020 Thank for sharing this nice information about scope function in Kotlin -- Reply Tor Mar 24, 2021 Of all the articles about scope functions I’ve read, this one was the most helpful. The use cases and examples are spot on. Thank you. ...