public class MainActivity extends Activity {	@Override	protected void onCreate(Bundle savedInstanceState) {		super.onCreate(savedInstanceState);		// 生成一个LinearLayout，作为布局容器来动态添加3个Button		final LinearLayout layout = new LinearLayout(this);		layout.setOrientation(LinearLayout.VERTICAL);		setContentView(layout);		// 生成3个Button		final Button btn1 = new Button(this);		btn1.setText("1");		btn1.setText("Button1");		final Button btn2 = new Button(this);		btn2.setText("2");		btn2.setText("Button2");		final Button btn3 = new Button(this);		btn3.setText("3");		btn3.setText("Button3");		// 动态把三个Button添加到		layout.addView(btn1);		layout.addView(btn2);		layout.addView(btn3);		// 点击按钮时，先把原来在布局容器layout上的删掉，再添加上局容器layout，这样本次添加的控件就会排序到最后，以理解动态添加控件的思路		btn1.setOnClickListener(new OnClickListener() {			@Override			public void onClick(View arg0) {				layout.removeView(btn1);				layout.addView(btn1);			}		});		// 同btn1一样道理		btn2.setOnClickListener(new OnClickListener() {			@Override			public void onClick(View arg0) {				layout.removeView(btn2);				layout.addView(btn2);			}		});		// 同btn1一样道理		btn3.setOnClickListener(new OnClickListener() {			@Override			public void onClick(View arg0) {				layout.removeView(btn3);				layout.addView(btn3);			}		});		setContentView(layout);	}}