点击事件的写法

内部实现onclickListener的接口

public class LinearLayoutActivity extends Activity {
    private Button bt_01;
    private Button bt_02;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_linear);
        bt_01 = (Button) findViewById(R.id.bt_01);
        bt_02 = (Button) findViewById(R.id.bt_02);
        
        bt_01.setOnClickListener(clickListener);
        bt_02.setOnClickListener(clickListener);
    }
    
    private OnClickListener clickListener = new OnClickListener() {
        @Override
        public void onClick(View v) {
            switch (v.getId()) {
            case R.id.bt_01:
                clickButton01();
                break;
            case R.id.bt_02:
                // click button 02
                break;
            }
        }
    };
    
    private void clickButton01() {
        // click button 01
    }
}

匿名内部类实现onclickListener

public class LinearLayoutActivity extends Activity  implements OnClickListener{
    private Button button = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_linear);
        button = (Button) findViewById(R.id.b1);
        button.setOnClickListener(new OnClickListener(){
            @Override
            public void onClick(View v) {
                //do something
            }});
    }
}

让当前的Activity实现onclickListener的接口

界面的按钮较多，1，2两种代码会比较臃肿

public class LinearLayoutActivity extends Activity  implements OnClickListener{
    private Button button = null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_linear);
        button = (Button) findViewById(R.id.b1);
        button.setOnClickListener(this);
    }
    public void onClick(View v) {
        //do something 
    }
}

在布局xml文件里面声明onclick属性

属性里的""包含的是java代码里方法名(一般不推荐使用这个)

Activity:

public class LinearLayoutActivity extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_linear);
    }

    public void clickButton(View v) {
        Intent intent = new Intent(this, RelativeLayoutActivity.class);
        startActivity(intent);
    }
}

Layout:

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:onClick="clickButton"
        android:text="button" />