Android注解控件

@Target(ElementType.FIELD)//表示用在字段上
@Retention(RetentionPolicy.RUNTIME)//表示在生命周期是运行时
public @interface InjectView {
	public int id() default 0;

	public String click() default "";

	public String longClick() default "";

	public String itemClick() default "";

	public String itemLongClick() default "";
}

public class EventListener implements OnClickListener, OnLongClickListener, OnItemClickListener,OnItemLongClickListener {

	private Object handler;
	
	private String clickMethod;
	private String longClickMethod;
	private String itemClickMethod;
	private String itemLongClickMehtod;
	
	public EventListener(Object handler) {
		this.handler = handler;
	}
	
	public EventListener click(String method){
		this.clickMethod = method;
		return this;
	}
	
	public EventListener longClick(String method){
		this.longClickMethod = method;
		return this;
	}
	
	public EventListener itemLongClick(String method){
		this.itemLongClickMehtod = method;
		return this;
	}
	
	public EventListener itemClick(String method){
		this.itemClickMethod = method;
		return this;
	}
	
	public boolean onLongClick(View v) {
		return invokeLongClickMethod(handler,longClickMethod,v);
	}
	
	public boolean onItemLongClick(AdapterView<?> arg0, View arg1, int arg2,long arg3) {
		return invokeItemLongClickMethod(handler,itemLongClickMehtod,arg0,arg1,arg2,arg3);
	}
	
	public void onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3) {
		
		invokeItemClickMethod(handler,itemClickMethod,arg0,arg1,arg2,arg3);
	}
	
	public void onClick(View v) {
		
		invokeClickMethod(handler, clickMethod, v);
	}
	
	
	private static Object invokeClickMethod(Object handler, String methodName,  Object... params){
		if(handler == null) return null;
		Method method = null;
		try{   
			method = handler.getClass().getDeclaredMethod(methodName,View.class);
			if(method!=null)
				return method.invoke(handler, params);	
			else
				throw new RuntimeException("no such method:"+methodName);
		}catch(Exception e){
			e.printStackTrace();
		}
		
		return null;
		
	}
	
	
	private static boolean invokeLongClickMethod(Object handler, String methodName,  Object... params){
		if(handler == null) return false;
		Method method = null;
		try{   
			//public boolean onLongClick(View v)
			method = handler.getClass().getDeclaredMethod(methodName,View.class);
			if(method!=null){
				Object obj = method.invoke(handler, params);
				return obj==null?false:Boolean.valueOf(obj.toString());	
			}
			else
				throw new RuntimeException("no such method:"+methodName);
		}catch(Exception e){
			e.printStackTrace();
		}
		
		return false;
		
	}
	
	
	
	private static Object invokeItemClickMethod(Object handler, String methodName,  Object... params){
		if(handler == null) return null;
		Method method = null;
		try{   
			///onItemClick(AdapterView<?> arg0, View arg1, int arg2, long arg3)
			method = handler.getClass().getDeclaredMethod(methodName,AdapterView.class,View.class,int.class,long.class);
			if(method!=null)
				return method.invoke(handler, params);	
			else
				throw new RuntimeException("no such method:"+methodName);
		}catch(Exception e){
			e.printStackTrace();
		}
		
		return null;
	}
	
	
	private static boolean invokeItemLongClickMethod(Object handler, String methodName,  Object... params){
		if(handler == null) throw new RuntimeException("invokeItemLongClickMethod: handler is null :");
		Method method = null;
		try{   
			///onItemLongClick(AdapterView<?> arg0, View arg1, int arg2,long arg3)
			method = handler.getClass().getDeclaredMethod(methodName,AdapterView.class,View.class,int.class,long.class);
			if(method!=null){
				Object obj = method.invoke(handler, params);
				return Boolean.valueOf(obj==null?false:Boolean.valueOf(obj.toString()));	
			}
			else
				throw new RuntimeException("no such method:"+methodName);
		}catch(Exception e){
			e.printStackTrace();
		}
		
		return false;
	}
}

public abstract class BaseActvity extends FragmentActivity {

	@Override
	public void setContentView(int layoutResID) {
		// TODO Auto-generated method stub
		super.setContentView(layoutResID);
		initInjectedView(this);
	}

	@Override
	public void setContentView(View view) {
		// TODO Auto-generated method stub
		super.setContentView(view);
		initInjectedView(this);
	}

	@Override
	public void setContentView(View view, LayoutParams params) {
		// TODO Auto-generated method stub
		super.setContentView(view, params);
		initInjectedView(this);
	}

	private void initInjectedView(Activity activity) {
		initInjectedView(activity, activity.getWindow().getDecorView());
	}

	private void initInjectedView(Object activity, View sourceView) {
		Field[] fields = activity.getClass().getDeclaredFields(); // 获取字段
		if (fields != null && fields.length > 0) {
			for (Field field : fields) {
				try {
					field.setAccessible(true); // 设为可访问

					if (field.get(activity) != null)
						continue;

					InjectView mView = field.getAnnotation(InjectView.class);
					if (mView != null) {

						int viewId = mView.id();
						if (viewId == 0)
							viewId = getResources().getIdentifier(field.getName(), "id", getPackageName());
						if (viewId == 0)
							Log.e("D3Activity", "field " + field.getName() + "not found");

						// 关键,注解初始化，相当于 backBtn = (TextView)
						// findViewById(R.id.back_btn);
						field.set(activity, sourceView.findViewById(viewId));
						// 事件
						setListener(activity, field, mView.click(), Method.Click);
						setListener(activity, field, mView.longClick(), Method.LongClick);
						setListener(activity, field, mView.itemClick(), Method.ItemClick);
						setListener(activity, field, mView.itemLongClick(), Method.itemLongClick);
					}
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		}
	}

	private void setListener(Object activity, Field field, String methodName, Method method) throws Exception {
		if (methodName == null || methodName.trim().length() == 0)
			return;

		Object obj = field.get(activity);

		switch (method) {
		case Click:
			if (obj instanceof View) {
				((View) obj).setOnClickListener(new EventListener(activity).click(methodName));
			}
			break;
		case ItemClick:
			if (obj instanceof AbsListView) {
				((AbsListView) obj).setOnItemClickListener(new EventListener(activity).itemClick(methodName));
			}
			break;
		case LongClick:
			if (obj instanceof View) {
				((View) obj).setOnLongClickListener(new EventListener(activity).longClick(methodName));
			}
			break;
		case itemLongClick:
			if (obj instanceof AbsListView) {
				((AbsListView) obj).setOnItemLongClickListener(new EventListener(activity).itemLongClick(methodName));
			}
			break;
		default:
			break;
		}
	}

	public enum Method {
		Click, LongClick, ItemClick, itemLongClick
	}
}

使用特方便：简化代码，提高效率，搬砖必备。。。

@InjectView(itemClick = "OnItemClick")ResizeGridView gridview1, gridview2, gridview3;

public void OnItemClick(AdapterView<?> parent, View view, int position, long id) {
// TODO Auto-generated method stub
switch (parent.getId()) {
case R.id.gridview1:
ToastUtil.showCustomToast(this, "gridview1:"+((EarnPointBean)parent.getAdapter().getItem(position)).title);
break;
case R.id.gridview2:
ToastUtil.showCustomToast(this, "gridview2:"+((EarnPointBean)parent.getAdapter().getItem(position)).title);
break;
case R.id.gridview3:
ToastUtil.showCustomToast(this, "gridview3:"+((EarnPointBean)parent.getAdapter().getItem(position)).title);
break;
}
}