android - 如何在Kotlin中定义应用程序类和静态变量

Question

如何在kotlin中编写等效代码，我需要使用定义的静态变量

public class ThisForThatApplication extends Application {

    static ThisForThatApplication appInstance;

    public static ThisForThatApplication getAppInstance() {
        if (appInstance == null) {
            appInstance = new ThisForThatApplication();
        }
        return appInstance;
    }
}

Answer 1

试试这个

class ThisForThatApplication : Application() {

    companion object {

        @JvmField
        var appInstance: ThisForThatApplication? = null



        @JvmStatic fun getAppInstance(): ThisForThatApplication {
            return appInstance as ThisForThatApplication
        }
    }

    override fun onCreate() {
        super.onCreate()
        appInstance=this;
    }

}

有关更多信息，请阅读 Static Fields 和 Static Methods