Android入门：Button

一、Button的继承结构

java.lang.Object

|-android.view.View

|-android.widget.TextView

|-android:widget.Button

二、Button使用

1.监听器

android.view.View.OnClickListener

        btn.setOnClickListener(new OnClickListener(){

			@Override
			public void onClick(View v) { //此处的View为Button，可强制类型转换
				
			}
        	
        });

实例：

package org.xiazdong;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;

public class MainActivity extends Activity {
	private Button btn;
    int i=0;
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        btn = (Button)this.findViewById(R.id.btn);
        btn.setOnClickListener(new OnClickListener(){
			@Override
			public void onClick(View v) {
				Button b = (Button)v;
				b.setText(""+(i++));
			}
        });
    }
}