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Air safety In Java, we don't have to force us to deal with null objects, so null pointerexception null pointers often appear. Now Kotlin restricts null objects. We must deal with whether the object is null at compile time, otherwise the compilation will fail When the object cannot be empty, you can use this object directly fun getText() : ...

preface This is a learning record of Kotlin collaboration on the Android official website. Record the characteristics and applications of Kotlin Coroutines on Android Overview of collaborative process 1, What is a collaborative process? Coprocessing is a concurrent design pattern that can be used to simplify asynchronously executed code. It can ...

The last article introduced the operation and recovery of the process, and this article introduces the parent-child process What is a subprocess Let's take an example here The coroutine created by the first launch represents the dead parent coroutine, and the coroutine created by the second launch represents the child coroutine. Note that th ...

Builder of collaborative process Both the launch and async builders are used to start new processes launch, which returns a job without any result value async returns a Deferred, which is also a job and can be used await() gets its final result on a Deferred value //Wait for a job: join and await private fun runBlocking1(){ // ...

1, Foreword In order to solve the problem of chaotic architecture design since the development of android app, Google launched the family bucket solution of jetpack MVVM. As the core of the whole solution, LiveData, with its life cycle security, memory security and other advantages, even has the trend to gradually replace EventBus and RxJava a ...

This article mainly shares the usage and differences of Kotlin's scope functions let, run, with, apply and also. During the execution of scope function, a temporary scope is formed through lambda expression, which can reduce the number of some logic codes. Context object: this or it this run, with, and apply reference context objects wi ...

IF expressionAn if statement contains a Boolean expression and one or more statements.// Traditional Use var max = a if (a < b) max = b // Use else var max: Int if (a > b) { max = a } else { max = b } // As an expression val max = if (a > b) a else bWe can also assign the result of the IF expression to a variable.val max ...

Python wechat ordering applet course video https://edu.csdn.net/course/detail/36074 Python practical quantitative transaction financial management system https://edu.csdn.net/course/detail/35475 Kotlin collaboration series article navigation: Kotlin process I - Coroutine Kotlin collaboration process 2 - Channel Kotlin collaboration process I ...

1. Introduction Retrofit's support for collaborative processes is very rudimentary. The use of kotlin does not conform to kotlin's elegance interface TestServer { @GET("banner/json") suspend fun banner(): ApiResponse<List<Banner>> } //Network request for parallel exception capture fun oldBanner(){ viewModelScope. ...

1. IntroductionRetrofit's support for collaborative processes is very rudimentary. The use of kotlin does not conform to kotlin's eleganceinterface TestServer { @GET("banner/json") suspend fun banner(): ApiResponse<List<Banner>> } //Network request for parallel exception capture fun oldBanner(){ viewModelScope.laun ...