事件就是用户与UI界面的交互时所触发的操作。比如点击某一个按钮，会触发一个事件等
1、最长用的按钮事件：OnClickListener
mybutton = (Button)findViewById(R.id.mybutton);
mybutton.setOnClickListener(new Button.OnClickListener()
{
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
ShowMessage("点击了Button按钮");
}
});
2、我们还可以自定义KeyEvent，比如
public boolean onKeyDown(int keyCode, KeyEvent event)
{
/**
* 这里构建KeyEvent对象，功能为返回键的功能
* 即我们按任意键都是返回键功能
*/
KeyEvent key = new KeyEvent(KeyEvent.ACTION_DOWN, KeyEvent.KEYCODE_BACK);
return super.onKeyDown(keyCode, event);
}
3、手机按键的事件处理
Boolean onKeyDown(int keyCode, KeyEvent event)：相应按键按下
Boolean onKeyUp(int keyCode, KeyEvent event)：相应按键释放
Boolean onKeyMultiple()：相应按键重复点击
Boolean onTouchEvent(MotionEvent event)：相应触屏事件
package org.hualang.eventtest01;
import android.app.Activity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class EventTest01 extends Activity {
/**
* 注意，要重写onKeyDown,onKeyUp,onTouchEvent方法
*/
private Button mybutton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mybutton = (Button)findViewById(R.id.mybutton);
mybutton.setOnClickListener(new Button.OnClickListener()
{
@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
ShowMessage("点击了Button按钮");
}
});
}
/**按键按下触发的事件*/
public boolean onKeyDown(int keyCode, KeyEvent event)
{
switch(keyCode)
{
case KeyEvent.KEYCODE_DPAD_CENTER:
ShowMessage("按下:中键");break;
case KeyEvent.KEYCODE_DPAD_UP:
ShowMessage("按下:上方向键");break;
case KeyEvent.KEYCODE_DPAD_DOWN:
ShowMessage("按下:下方向键");break;
case KeyEvent.KEYCODE_DPAD_LEFT:
ShowMessage("按下:左方向键");break;
case KeyEvent.KEYCODE_DPAD_RIGHT:
ShowMessage("按下:右方向键");break;
}
return super.onKeyDown(keyCode, event);
}
/**按键弹起所触发的事件*/
public boolean onKeyUp(int keyCode, KeyEvent event)
{
switch(keyCode)
{
case KeyEvent.KEYCODE_DPAD_CENTER:
ShowMessage("弹起:中键");
break;
case KeyEvent.KEYCODE_DPAD_DOWN:
ShowMessage("弹起:下方向键");
break;
case KeyEvent.KEYCODE_DPAD_UP:
ShowMessage("弹起:上方向键");
break;
case KeyEvent.KEYCODE_DPAD_LEFT:
ShowMessage("弹起：左方向键");
break;
case KeyEvent.KEYCODE_DPAD_RIGHT:
ShowMessage("弹起:右方向键");
break;
}
return super.onKeyUp(keyCode, event);
}
/**按键重复点击事件*/
public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event)
{
return onKeyMultiple(keyCode, repeatCount, event);
}
/**触屏事件*/
public boolean onTouchEvent(MotionEvent event)
{
int action = event.getAction();
if(action == MotionEvent.ACTION_CANCEL||action == MotionEvent.ACTION_DOWN||action == MotionEvent.ACTION_MOVE)
{
return false;
}
//得到触点的位置
String x = String.valueOf(event.getX());
String y = String.valueOf(event.getX());
ShowMessage("触点坐标：(" + x + "," + y +")");
return super.onTouchEvent(event);
}
/**显示触发事件的信息*/
public void ShowMessage(String str)
{
Toast toast = Toast.makeText(this, str, Toast.LENGTH_SHORT);
toast.show();
}
}
运行结果如下：
- 查看图片附件