Question

我不确定从适配器到相应活动的最佳通信方式是什么。

我的活动的布局包含WebView和Gallery：

<?xml version="1.0" encoding="utf-8"?>

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_height="fill_parent"
    android:layout_width="fill_parent"
    android:orientation="vertical" >

    <Gallery 
        android:id="@+id/gallery"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:layout_width="fill_parent"
        android:spacing="2dip" />       

    <WebView
        android:id="@+id/webview"
        android:layout_height="wrap_content"
        android:layout_weight="5"
        android:layout_width="fill_parent" />
</LinearLayout>

活动将图像数据加载到图库中：

public class MyActivity extends Activity {

  private MyAdapter            adapter;
  private Container            container;
  private ArrayList<Container> containers = new ArrayList<Container>();
  private Gallery              gallery;
  private WebView              webView;

  @Override
  public void onCreate(Bundle bundle) {
    ...
    gallery = (Gallery) findViewById(R.id.gallery);
    webView = (WebView) findViewById(R.id.webview);

    containers = fetchContainers();
    doGallery();
  }

  private void doGallery() {
    adapter = new MyAdapter(this,
                            containers);
    gallery.setAdapter(adapter);
  }

  private ArrayList<Container> fetchContainers() {
    ArrayList<Container> containers = null;
    ...
    return containers;
  }
}

单击其中一个图像应更改webview的内容。这是带有OnClickListener的适配器：

public class MyAdapter extends BaseAdapter {

  private class MyOnClickListener implements OnClickListener {

    private Container container; 
    private Context   context; 

    public MyOnClickListener(Context context, Container container) {
      this.container = container;
      this.context = context;
    }

    public void onClick(View view) {
      //TODO: change contents of WebView
    }
  }

  private ArrayList<Container> containers;
  private Context              context;

  public View getView(final int position, final View contentView, final ViewGroup viewGroup) {
    ImageView imageView = new ImageView(context);
    Container container = containers.get(position);
    // get image data from image cache
    imageView.setOnClickListener(new MyOnClickListener(context, container));
    return imageView;
  }

  public MyAdapter(Context context, ArrayList<Container> containers) {
    this.containers = containers;
    this.context = context;
  }
}

现在我的问题是。如何通知活动有关已点击的图像并将一个对象传输到活动？

我的想法是使用BroadcastReceiver，但我不认为这是首选方式。我该怎么办？

非常感谢提前。

Answer 1

改为创建Imageview的点击监听器，使用gallery的setOnItemClickListener

 yourGallery.setOnItemClickListener(new OnItemClickListener() 
 {
     @Override
     public void onItemClick(AdapterView<?> arg0, View arg1,int position, long arg3) {

         system.out.println("position"+position);               

     }
 });

Answer 2

在活动中使用Gallery对象的setOnItemClickListener方法。

如何在Adapter和Activity之间进行通信

2 个答案: