button單擊事件的四種寫法

Button單擊事件的四種寫法：

    1、第一種寫法：匿名內(nèi)部類

    附上代碼：

public class MainActivity extends Activity{

        private Button btn ;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btn = (Button) findViewById(R.id.btn) ;

//第一種寫法:匿名內(nèi)部類

                btn.setOnClickListener(new View.OnClickListener() {

                    @Override

                    public void onClick(View v) {

                        Toast.makeText(MainActivity.this, "我彈出來了", 0).show() ;

                    }

                }) ;

        }

}

    2、創(chuàng)建內(nèi)部類

public class MainActivity extends Activit{

    private Button btn ;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btn = (Button) findViewById(R.id.btn) ;

btn.setOnClickListener(new MyListener() ) ;

}

    class MyListener implements View.OnClickListener{

@Override

        public void onClick(View v) {

            Toast.makeText(MainActivity.this, "我彈出來了哈哈", 0).show() ;

        }

    }

}

    3、用窗體實(shí)現(xiàn)監(jiān)聽器

public class MainActivity extends Activity implements View.OnClickListener {

        private Button btn ;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btn = (Button) findViewById(R.id.btn) ;

//第三種：用窗體實(shí)現(xiàn)監(jiān)聽器

                btn.setOnClickListener(this) ;

}

@Override

public void onClick(View v) {

Toast.makeText(MainActivity.this, "哈哈,我來了", 0).show() ;

}

}

    4、通過屬性聲明

public class MainActivity extends Activity{

        private Button btn ;

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main);

btn = (Button) findViewById(R.id.btn) ;

            }

//第四種： 通過屬性聲明

public void click(View view){

Toast.makeText(MainActivity.this, "哈哈哈哈哈", 0).show() ;

}

}

以上有背景色的部分為各種方法的關(guān)鍵代碼。