*等价于Java:public static final String TAG=BaseActivity.class.getSimpleName()*/ //定义标志 val TAG: String = this.javaClass.simpleName //初始化布局View abstract fun initView() //初始化数据 abstract fun initData() //初始化获取布局id,带返回值的抽象方法 abstract fun getLayoutId(): Int /*...
Class 'Xxx' is not abstract and does not implement abstract member public abstract fun surfaceChanged(p0: SurfaceHolder, p1: Int, p2: Int, p3: Int): Unit defined in android.view.SurfaceHolder.Callback 在 编译版本 compileSdkVersion 和 目标版本 targetSdkVersion 都为 28 时, 编译不报上述错误...
编译时报错如下 : Class 'Xxx' is not abstract and does not implement abstract member public abstract fun surfaceChanged(p0: SurfaceHolder, p1: Int, p2: Int, p3: Int): Unit defined in android.view.SurfaceHolder.Callback 在 编译版本 compileSdkVersion 和 目标版本 targetSdkVersion 都为 28 2828...
The kotlin abstract class is one of the keywords, and it is used to declare and create the class. It cannot be instantiated also unable to create the object for the class, variables, methods, and other default functions attributes also used the abstract keyword. It does not need to annotate...
In this article, you will learn about abstract class and how to implement it in Kotlin (with the help of examples).
() }//implement base class abstract methodoverridefundraw(){ println("draw Method , override in Child Class") }//Override method, provide different implementationoverridefunpaint(){ println("Paint Method , Child Class Implementation") }//Declare Method to print Property valuefunprintValue(){ ...
与Java不同的是Kotlin允许接口内部有具体的方法实现,而不是像Java那样严格要求所有的方法都必须是抽象方法。但一旦是经具体实现的方法,就不能在其前面加上abstractt关键字。 Java里面的继承和实现分别是通过extends和implement两个关键字实现的,Kotlin里这两个关键字都被符号“:”替代了。
defaultConfig { applicationId "com.xxx.xxx" minSdkVersion 19 targetSdkVersion 30 versionCode 1 versionName "0.1" } } 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 编译时报错如下 : Class 'Xxx' is not abstract and does not implement abstract member public abstract fun surfaceChange...
abstractclassShape{funarea():Double{throwNotImplementedError("You should implement this method") }funperimeter():Double{return2* (area() / Math.PI).toDouble() } }classCircle(radius:Double) : Shape() {overridefunarea():Double{returnMath.PI * radius * radius ...
继承:在Kotlin里,继承关系统一用“:”,不需要向java那样区分implement和extend,在继承多个类/接口时,中间用“,”区分即可,另外,在继承类时,类后面要跟()。所以在Kotlin里,继承类和接口的代码一般是这样的: class BaseClass : Activity(), IBinder{ //示例 ...