自定义ButterKnife

compile 'com.jakewharton:butterknife:8.8.1'annotationProcessor 'com.jakewharton:butterknife-compiler:8.8.1'

activity_main.xml

<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:app="http://schemas.android.com/apk/res-auto"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:orientation="vertical">    <Button        android:id="@+id/bt1"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="按钮1" />    <Button        android:id="@+id/bt2"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="按钮2" />    <Button        android:id="@+id/bt3"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="按钮3" />    <Button        android:id="@+id/bt4"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:text="按钮4" /></LinearLayout>

IBindView.java

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 lenovo on 2017/11/28. */@Documented@Target(ElementType.FIELD)//作用域@Retention(RetentionPolicy.RUNTIME)//运行时在作用public @interface IBindView {    int value();}

IOnClick.java

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 lenovo on 2017/11/28. */@Documented@Target(ElementType.METHOD)//方法@Retention(RetentionPolicy.RUNTIME)public @interface IOnClick {    int value();}

MainActivity.java

package panjiangang.bwie.com.lianxi1_day02;import android.app.Activity;import android.os.Bundle;import android.support.v7.app.AppCompatActivity;import android.view.View;import android.widget.Button;import android.widget.Toast;import java.lang.reflect.Field;import java.lang.reflect.InvocationTargetException;import java.lang.reflect.Method;public class Main2Activity extends AppCompatActivity {    @IBindView(R.id.bt1)    public Button bt1;    @IBindView(R.id.bt2)    public Button bt2;    @IBindView(R.id.bt3)    public Button bt3;    @IBindView(R.id.bt4)    public Button bt4;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        initId(this);//        initClick(this);//有监听事件的方法        bt1.setText("A");        bt2.setText("B");        bt3.setText("C");        bt4.setText("D");    }    public static void initId(Activity activity) {        Class clazz = activity.getClass();        //获取当前类的所有属性        Field[] fields = clazz.getFields();//所有公开的字段 (属性)        // 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(IBindView.class)) {                // 获取当前属性身上的注解                IBindView iBindView = field.getAnnotation(IBindView.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();                }            }        }    }    public static void initClick(final Activity activity) {        Class clazz = activity.getClass();        Field[] fields = clazz.getDeclaredFields();        for (Field field : fields) {            if (field.isAnnotationPresent(IBindView.class)) {                IBindView bindView = field.getAnnotation(IBindView.class);                View view = activity.findViewById(bindView.value());                try {                    field.set(activity, view);                    // 获取当前类的public 方法                    Method[] methods = clazz.getMethods();                    for (final Method method : methods) {                        //判断当前方法上是否有IOnClick 注解                        if (method.isAnnotationPresent(IOnClick.class)) {                            //获取方法上的注解                            IOnClick click = method.getAnnotation(IOnClick.class);                            // 获取注解值                            int id = click.value();                            //点击事件出发条件                            if (bindView.value() == id) {                                view.setOnClickListener(new View.OnClickListener() {                                    @Override                                    public void onClick(View view) {                                        try {                                            // 调用点击事件方法                                            method.invoke(activity);                                        } catch (IllegalAccessException e) {                                            e.printStackTrace();                                        } catch (InvocationTargetException e) {                                            e.printStackTrace();                                        }                                    }                                });                            }                        }                    }                } catch (IllegalAccessException e) {                    e.printStackTrace();                }            }        }    }    @IOnClick(R.id.bt4)    public void onViewClicked() {        Toast.makeText(this, "bt4", Toast.LENGTH_SHORT).show();    }}