Question

我正在尝试做3个意图来开始新活动，但是我发现我总是得到一个错误。我把我的代码放到main.java上代码：

public class Main extends Activity {
Button service;
Button gallery;
Button contact;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    service = (Button)findViewById(R.id.Services);
    service.setOnClickListener(new View.OnClickListener() {
    });
    gallery = (Button)findViewById(R.id.Gallery);
    gallery.setOnClickListener(new View.OnClickListener() {
    }); 
    contact = (Button)findViewById(R.id.Contact);
    contact.setOnClickListener(new View.OnClickListener() {
    });


        public void onClick (View v) {
    // Inflate the menu; this adds items to the action bar if it is present.
    Intent intent = new Intent (Main.this, servicesActivity.class);
startActivity(intent);
        }
public void onClick1 (View v) {
    Intent intent1 = new Intent (Main.this, galleryActivity.class);
startActivity(intent1);
}
public void onClick2 (View v) {
    Intent intent2 = new Intent (Main.this, contactActivity.class);
startActivity(intent2);
        }

}
}

我尝试了不同的方法，甚至将括号放在不同的地方。我也在互联网上搜索了几个星期，发现没有什么可以超过1。我在 OnClick和新的View.OnClickListener（）上遇到错误。我有一个工作，这就是为什么我用3个按钮尝试相同的代码。基本上我在main activity.xml上有3个按钮。我想做的就是：

>'button1 >goes> activity1'
>'button2 >goes> activity2'
>'button3 >goes> activity3'

请给我任何提示或提示，因为我是Android开发人员的新手。

Answer 1

您可以在同一listener内完成所有这些操作。以这种方式设置所有listeners

service.setOnClickListener(this);
gallery.setOnClickListener(this);

然后使用一个函数并检查点击的id的{{1}}

View

你可以实际清理它，以便不用这样的东西重复变量

public void onClick2 (View v) {
Intent intent = new Intent();
switch (v.getId())  // get the id of the Button clicked
{
   case (R.id.Services):
      intent = new Intent(Main.this, servicesActivity.class);
      break;
   case (R.id.Gallery):
       intent = new Intent(Main.this, galleryActivity.class);
       break;
...
}
startActivity(intent);

正如dymeh指出的那样，请确保public void onClick(View v) { Intent intent = new Intent(); // create an Intent String act = null; // name for Activity to start with Intent String shield = "com.your.package."; // set package name switch (v.getId()) // get the id of the Button clicked { case (R.id.Services): act = package + "Services"; // if Services button clicked use Services as the activity break; case (R.id.Gallery): act = package + "GalleryActivity"; break; ... } try { intent = new Intent(Main.this, Class.forName(act)); // create your Intent by changing your String act to a class name startActivity(intent); // start the Intent as normal } catch (ClassNotFoundException e){ // don't forget to catch invalid class names e.printsStackTrace(); } Activity

这可能会被清理一点，可能看起来更难，但我在自定义菜单和其他地方使用这样的东西，它很好地工作。它减少了单独的功能并创建了单独的implements OnClickListener。如果您以后必须添加内容或想要重用代码，那么它会更容易一些，恕我直言

Answer 2

public class Main extends Activity {
Button service;
Button gallery;
Button contact;


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    service = (Button)findViewById(R.id.Services);
    service.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {

            Intent intent = new Intent (Main.this, servicesActivity.class);
            startActivity(intent);
        }

    });
    gallery = (Button)findViewById(R.id.Gallery);
    gallery.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {
            Intent intent1 = new Intent (Main.this, galleryActivity.class);
                startActivity(intent1);

        }

    }); 
    contact = (Button)findViewById(R.id.Contact);
    contact.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v)
        {
            Intent intent2 = new Intent (Main.this, contactActivity.class);
                  startActivity(intent2);

        }

    });

}

怎么做多个意图？

2 个答案: