使用 Switch 语句处理按钮点击 [英] Using Switch Statement to Handle Button Clicks

问题描述

我正在尝试围绕视图、侦听器等进行思考.我有一个带有 2 个按钮的活动:buttonplay 和 buttonstop.我的问题是我无法完全围绕 Views 和 Listeners 生成一个有效的 switch 语句.

I'm trying to wrap my head around Views, Listeners etc. I have an Activity with 2 Buttons: buttonplay and buttonstop. My problem is I can't wrap my head around the Views and Listeners completely enough to generate a working switch statement.

例如，我想创建一个 SINGLE Listener 并以某种方式使用它来确定单击了哪个按钮.然后以某种方式使用在我的 switch 语句中单击的按钮的 ID，但我在网上找到的所有内容似乎都对每个按钮使用了单独的侦听器，然后以某种方式使用 View 作为 Switch 语句的参数.

For example, I would LIKE to create a SINGLE Listener and somehow use it to determine which button is clicked. Then somehow use the ID of the button clicked in my switch statement, But everything I find online seems to use SEPARATE listeners for every button and then somehow use the View as the argument to the Switch statement.

我意识到下面的代码不正确，但我正在寻找完成上述操作所需的更改.

I realize the code below is not correct, but am looking for what changes I would need to accomplish the above.

我想根据单击的按钮来控制 MediaPlayer.我有:

I want to control the MediaPlayer depending on which button is clicked. I have:

   Button b1 = (Button) findViewById(R.id.buttonplay);       
    b1.setOnClickListener(new View.OnClickListener()         
    {

        public void onClick(View v) {
           // Perform action on click
          switch(v.getId()) {
          case R.id.buttonplay:
          //Play voicefile
          MediaPlayer.create(getBaseContext(), R.raw.voicefile).start();
          break;
          case R.id.buttonstop:
          //Stop MediaPlayer
              MediaPlayer.create(getBaseContext(), R.raw.voicefile).stop();
          break;
         }
   }
    });

最终，我想要最直接的方式来打开单击的任何按钮.我相信我的大部分困惑源于在这种情况下使用 onClickListeners 和 Views 的方式.

Ultimately I would like the most straighforward way to switch on whatever button is clicked. I believe a big part of my confusion stems from the way onClickListeners and Views are used in this context.

推荐答案

实现此目的的一种方法是让您的类实现 OnClickListener，然后将其添加到您的按钮中，如下所示:

One way of achieving this is to make your class implement OnClickListener and then add it to your buttons like this:

示例:

//make your class implement OnClickListener
public class MyClass implements OnClickListener{

        ...

        //Create your buttons and set their onClickListener to "this"
        Button b1 = (Button) findViewById(R.id.buttonplay);   
        b1.setOnClickListener(this);

        Button b2 = (Button) findViewById(R.id.buttonstop);   
        b2.setOnClickListener(this);

        ...

        //implement the onClick method here
        public void onClick(View v) {
           // Perform action on click
          switch(v.getId()) {
            case R.id.buttonplay:
              //Play voicefile
              MediaPlayer.create(getBaseContext(), R.raw.voicefile).start();
              break;
            case R.id.buttonstop:
              //Stop MediaPlayer
              MediaPlayer.create(getBaseContext(), R.raw.voicefile).stop();
              break;
          }
       }
}

有关详细信息，请参阅Android 开发人员 > 处理 UI 事件.

For more information see Android Developers > Handling UI Events.

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