simple适配器缩略图和文本以及 onItemClick 处理程序

Question

在我的应用程序中，我需要显示一个缩略图列表及其自己的相对标题。这是我的实现。

    String tempTarget;
    List<Map<String,Object>> data = new ArrayList<Map<String,Object>>();
   for(int i = 0; i<ARelements.size();i++){
        Element ar = arIterator.next();
        Map<String,Object> map = new HashMap<String,Object>(2);
        tempTarget = ar.getAttributeValue("TARGET");
        thumbnailBitmap = ThumbnailUtils.extractThumbnail(BitmapFactory.decodeFile(tempTarget), THUMBSIZE, THUMBSIZE);
        map.put("thumbnail", thumbnailBitmap);
        map.put("titolo", tempTarget);
        data.add(map);
        Log.i("list",thumbnailBitmap.toString());
    }
   arIterator= null;
   SimpleAdapter simpleAdapter = new SimpleAdapter(this,data,R.layout.row,new String[] {"thumbnail","titolo"},new int[] {R.id.imageView, R.id.titoloTv});

    listView.setAdapter(simpleAdapter);
    listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {  
           @Override  
           public void onItemClick(AdapterView<?> adapter, final View componente, int pos, long id){  
               List<Map<String,Object>> res =  new ArrayList<Map<String,Object>>();
               res =  (List<Map<String, Object>>) adapter.getItemAtPosition(pos); //classCastExeption
               Log.i("list","assegamento a res eseguito");
               titoloriga = (String) res.get(pos).get("titolo");
               Log.i("list","assegamento a titoloriga eseguito");
               Log.i("list", "Ho cliccato sull'elemento con titolo" + titoloriga+"    " +Integer.valueOf(pos)+"    "+Long.valueOf(id));
               registerForContextMenu(componente);
               componente.showContextMenu();
           } 
    }); 

我有两个问题：1.简单的适配器仅显示标题，而不显示缩略图。2.我不知道如何处理onItemClick，我需要存储标题。通过这种方式，我有了ClassCastExeption和不安全的警告。下面是单行和列表视图的布局。

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:orientation="horizontal" >
<ImageView
    android:id="@+id/imageView"
    android:layout_width="65dp"
    android:layout_height="65dip"
     />
<TextView
    android:id="@+id/titoloTv"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_toRightOf="@id/imageView"
    android:textAppearance="?android:attr/textAppearanceMedium" />
</RelativeLayout>

和

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >
<Button
    android:id="@+id/creaButton"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center_horizontal"
    android:text="Crea una nuova realtà aumentata" />
<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center_horizontal"
    android:text="Ar già create"
    android:textAppearance="?android:attr/textAppearanceLarge" />
<ListView
    android:id="@+id/listView1"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >
</ListView>
</LinearLayout>

谢谢的

Answer 1

在 ListView 的项目单击上，您无需再次创建哈希映射数组列表，您可以通过它存储在哈希映射的 ArrayList 中获取。所以改变

   listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {  
       @Override  
       public void onItemClick(AdapterView<?> adapter, final View componente, int pos, long id){  
           String title = data.get(pos).get("titolo");
           String thumbimage = data.get(pos).get("thumbnail");
           registerForContextMenu(componente);
           componente.showContextMenu();
       } 
});