添加onclick监听器到预定义按钮？

Question

我的xml布局文件中有以下按钮...

<Button
    android:layout_width="150dip"
    android:id="@+id/button1"
    android:layout_height="50dip"
    android:text="@string/login"
    android:layout_marginRight="10dip">
</Button>

我想以编程方式onclick()在其Java文件中添加一个监听器.我该怎么做？

Answer 1

你只需要这样的东西:

Button buttonOne = (Button) findViewById(R.id.button1);
buttonOne.setOnClickListener(new Button.OnClickListener() {
    public void onClick(View v) {
            //Do stuff here
    }
});

Answer 2

这个答案来自五种方式来连接一个事件监听器.请阅读该博文,以获得作者更全面的解释.请参阅我的其他答案,了解为添加多个onClick侦听器而重做的这五种方法.

1.会员等级

public class main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //attach an instance of HandleClick to the Button
        findViewById(R.id.button1).setOnClickListener(new HandleClick());
    }    
    private class HandleClick implements OnClickListener{
        public void onClick(View arg0) {
            Button btn = (Button)arg0;  //cast view to a button
            // get a reference to the TextView
            TextView tv = (TextView) findViewById(R.id.textview1);
            // update the TextView text
            tv.setText("You pressed " + btn.getText());
        }
    }
}

2.接口类型

public class main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        //use the handleClick variable to attach the event listener
        findViewById(R.id.button1).setOnClickListener(handleClick);
    }    
    private OnClickListener handleClick = new OnClickListener(){
        public void onClick(View arg0) {
            Button btn = (Button)arg0;
            TextView tv = (TextView) findViewById(R.id.textview1);
            tv.setText("You pressed " + btn.getText());
        }
    };
}

3.匿名内部阶级

public class main extends Activity {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        findViewById(R.id.button1).setOnClickListener(new OnClickListener(){
            public void onClick(View arg0) {
            Button btn = (Button)arg0;
            TextView tv = (TextView) findViewById(R.id.textview1);
            tv.setText("You pressed " + btn.getText());
            }
        });
    }     
}

4.活动实施

public class main extends Activity implements OnClickListener{
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        findViewById(R.id.button1).setOnClickListener(this);
    }    
    public void onClick(View arg0) {
        Button btn = (Button)arg0;
        TextView tv = (TextView) findViewById(R.id.textview1);
        tv.setText("You pressed " + btn.getText());
    }
}

5. OnClick事件的视图布局中的属性

public class main extends Activity{
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }    
    public void HandleClick(View arg0) {
        Button btn = (Button)arg0;
        TextView tv = (TextView) findViewById(R.id.textview1);
        tv.setText("You pressed " + btn.getText());
    }
}

XML:

<Button android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button 1"
        android:onClick="HandleClick"/>

Answer 3

你可以试试这个.

public class myNewClass extends Activity implements OnClickListener {
    ................... 
    ...................       

    Button button = (Button)findViewById(R.id.button1);
    button.setOnClickListener(this);

        public void onClick(View v) {
                Intent i = new Intent();
                Bundle extras = new Bundle();

        // This will catch the button click 
        // Now do what you wanted to do as a 
        // result of the onClick
        }
 }