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Android中定义接口的用法

1、接口方法用于回调(这里定义接口是为了使用其接口方法):
 
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public inte易做图ce ICallback {
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  public void   func();
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}
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public class Caller {
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  ICallback callback;
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  public void doCallback() {
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    callback.func();
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  }
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  public void setCallback(ICallback callback) {
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    this.callback = callback;
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  }
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}
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public class MainClass {
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  public MainClass() {
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  }
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  public static void main(String[] args) {
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    Caller caller = new Caller();
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    caller.setCallback(new ICallback () {
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      public void func() {
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        System.out.println("dosth");
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      }
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    });
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    caller.doCallback();
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  }
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}
2、向上转型
 
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inte易做图ce People{
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   void peopleList();
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}
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class Student implements People{
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   public void peopleList(){
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       System.out.println("I’m a student.");
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  }
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}
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class Teacher implements People{
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   public void peopleList(){
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       System.out.println("I’m a teacher.");
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   }
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}
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public class Example{
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   public static void main(String args[]){
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       People a;             //声明接口变量
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       a=new Student();      //实例化,接口变量中存放对象的引用
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       a.peopleList();        //接口回调
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       a=new Teacher();     //实例化,接口变量中存放对象的引用
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       a.peopleList();       //接口回调
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  }
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}
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运行结果:
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I’m a student.
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I’m a teacher.
3、常量接口(这里不在讲)
补充:移动开发 , Android ,
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