_007_Android_给按钮添加一个点击事件

• activity_main.xml

 <Button
        android:id="@+id/button"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button"
        tools:layout_gravity="center_vertical" />

• MainActivity

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        findViewById(R.id.button).setOnClickListener(
               new View.OnClickListener(){
                   @Override
                   public void onClick(View view) {
                       Toast.makeText(MainActivity.this,"hello,hello",Toast.LENGTH_LONG).show();
                   }
               }
        );
    }
}