Android事件处理（六）

          这里接着上节课的内容，现在我们是要把2,3节课学到的组件的事件监听方法全部练一遍，所以接下来就是

• 监听日期与时间的改变
• 焦点事件

一下是.java代码：

package com.example.timelongclick;

import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.widget.DatePicker;
import android.widget.DatePicker.OnDateChangedListener;
import android.widget.EditText;
import android.widget.TimePicker;
import android.widget.TimePicker.OnTimeChangedListener;

public class Timelong extends Activity {

	private TimePicker time=null;
	private DatePicker date=null;
	private EditText show=null;
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_timelong);
		this.show=(EditText)super.findViewById(R.id.editText1);
		this.date=(DatePicker)super.findViewById(R.id.datePicker1);
		this.time=(TimePicker)super.findViewById(R.id.timePicker1);
		this.time.setIs24HourView(true);
		this.time.setOnTimeChangedListener(new onTimeChanged());
		this.date.init(this.date.getYear(), this.date.getMonth(), this.date.getDayOfMonth(), new onDateChanged());
		this.setDateTime();
	}

	private void setDateTime() {
		this.show.setText(this.date.getYear()+"-"+(this.date.getMonth()+1)+"-"+this.date.getDayOfMonth()+"  "
				+this.time.getCurrentHour()+":"+this.time.getCurrentMinute());
		
	}
   private class onTimeChanged implements OnTimeChangedListener{

	@Override
	public void onTimeChanged(TimePicker arg0, int arg1, int arg2) {
		Timelong.this.setDateTime();
		
	}
	   
   }
   private class onDateChanged implements OnDateChangedListener{

	@Override
	public void onDateChanged(DatePicker arg0, int arg1, int arg2, int arg3) {
		// TODO Auto-generated method stub
		Timelong.this.setDateTime();
	}
	   
   }
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.timelong, menu);
		return true;
	}

}

这里有两个比较重要的监听器：

OnTimeChangedListe和OnDateChangedListener

以上代码是实现监听时间的改变，并显示出来

焦点实例，定义一个显示框，二个输入框，其中一个框绑定焦点事件，也就是在这个框输入时显示获得焦点，若离开框则失去焦点。

这里是主界面
 

public class Timelong extends Activity {

	private EditText edit=null;
	private TextView text=null;
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_timelong);
		this.edit=(EditText)super.findViewById(R.id.edit);
		this.text=(TextView)super.findViewById(R.id.text);
		this.edit.setOnFocusChangeListener(new Focus());
	}
	public void onClick(View v){
		this.edit.setText("");
	}
	private class Focus implements OnFocusChangeListener{

		@Override
		public void onFocusChange(View v, boolean focus) {
		if(v.getId()==Timelong.this.edit.getId()){
			if(focus){
				Timelong.this.text.setText("文本组件获得焦点");
			}
			else if(Timelong.this.edit.getText().length()>0){
				Timelong.this.text.setText("文本组件失去焦点");
			}
			else{
				Timelong.this.text.setText("文本组件失去焦点2");
			}
		}
			
		}
		
	}

	
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.timelong, menu);
		return true;
	}

}

• 
   长按事件   这里也是个重点，相信大家用过很多长按事件吧像长按保存图片复制粘贴等功能，这里我们要做到一个长按图片换成手机背景图的实例，做自己的换背景图神器是不是有点小期待呢？

首先我们要在配置文件xml里定义TextView和ImageView

然后设置换图片权限：

1. <uses-permissionandroid:name="android.permission.SET_WALLPAPER"/>

 
 代码：

public class Timelong extends Activity {

	
	private TextView text=null;
	private ImageView image=null;
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_timelong);
		
		this.text=(TextView)super.findViewById(R.id.text);
		this.image=(ImageView)super.findViewById(R.id.image);
		this.image.setOnLongClickListener(new LongClick());
		
	}
	private class LongClick implements OnLongClickListener{

		@Override
		public boolean onLongClick(View arg0) {
           
            try {
            	 Timelong.this.clearWallpaper();
				Timelong.this.setWallpaper(Timelong.this.image.getResources().openRawResource(R.drawable.wall));
			} catch (NotFoundException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			} catch (IOException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}

			return false;
		}
		
	}
	

	
	@Override
	public boolean onCreateOptionsMenu(Menu menu) {
		// Inflate the menu; this adds items to the action bar if it is present.
		getMenuInflater().inflate(R.menu.timelong, menu);
		return true;
	}

}

 显示效果如下：

返回手机界面发现图片换好啦，有兴趣可以做一个好一点的换图神器啦