有关Botton的用法（二）

1     <Button
2         android:layout_width="wrap_content"
3         android:layout_height="wrap_content"
4         android:text="Button1"
5         android:id="@+id/button1"
6         android:layout_below="@+id/textView"
7         android:layout_alignParentLeft="true"
8         android:layout_alignParentStart="true" />

 1 public class MainActivity extends Activity implements OnClickListener {//1.tell android you are interested in listening to a button click
 2 
 3     Button button;
 4     @Override
 5     protected void onCreate(Bundle savedInstanceState) {
 6         super.onCreate(savedInstanceState);
 7         setContentView(R.layout.activity_main);
 8         button = (Button)findViewById(R.id.button1);//2.bring your xml button inside java
 9         button.setOnClickListener(this);//3.tell your java button whose responding when it‘s clicked
10     }
11 
12     @Override//4.what should happen when button is clicked
13     public void onClick(View v) {
14         Log.e("MainActivity","Clicked1");
15     }
16 
17 }