Butterknif自定义view注解 不用依赖

 

package com.example.app3.butterknifezhujie;

import android.app.Activity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

import com.example.app3.R;

import java.lang.reflect.Field;



public class BufferActivity extends AppCompatActivity {


    @IBinView(R.id.button04)
    public Button Button04;
    @IBinView(R.id.button01)
    public   Button Button01;
    public Button getButton02;


    @IBinView(R.id.button02)
    public  Button Button02;
    @IBinView(R.id.button03)
    public Button Button03;


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_buffer);

        //有4注解


          initId(this);

            Button01.setText("1509D");
            Button02.setText("1509D");
            Button03.setText("1509D");
            Button04.setText("1509D");



    }

    public static   void initId(Activity activity){
        Class clazz =   activity.getClass() ;

        //获取当前类的所有属性
        Field [] fields =  clazz.getFields();
        // 遍历属性
        for (Field field : fields){
            // 判断当前属性 身上是否有IBindView 注解
            if(field.isAnnotationPresent(IBinView.class)){
                // 获取当前属性身上的注解
                IBinView iBindView =   field.getAnnotation(IBinView.class);
                //取出注解 对应的值
                int id = iBindView.value();
                //查找控件
                View view =  activity.findViewById(id);
                try {
                    // 把view 设置给当前的属性
                    field.set(activity,view);
                } catch (IllegalAccessException e) {
                    e.printStackTrace();
                }
            }

        }


    }

}

package com.example.app3.butterknifezhujie;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

/**
 * Created by gq on 2017/11/29.
 */

@Documented
@Target(ElementType.FIELD)//作用在字段
@Retention(RetentionPolicy.RUNTIME) //运行时

 public @interface IBinView {
     int value();  //注解里面的方法都是抽象方法

  }