的ListView onItemClickListener

錯誤：的ListView onItemClickListener

09-26 13:09:38.551: E/AndroidRuntime(25966): FATAL EXCEPTION: main 
09-26 13:09:38.551: E/AndroidRuntime(25966): java.lang.ClassCastException: java.util.HashMap 
09-26 13:09:38.551: E/AndroidRuntime(25966): at com.example.customlayoutlistview.MainActivity$1.onItemClick(MainActivity.java:79) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.widget.AdapterView.performItemClick(AdapterView.java:284) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.widget.ListView.performItemClick(ListView.java:3584) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.widget.AbsListView$PerformClick.run(AbsListView.java:1846) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.os.Handler.handleCallback(Handler.java:587) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.os.Handler.dispatchMessage(Handler.java:92) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.os.Looper.loop(Looper.java:130) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at android.app.ActivityThread.main(ActivityThread.java:3687) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at java.lang.reflect.Method.invokeNative(Native Method) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at java.lang.reflect.Method.invoke(Method.java:507) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:867) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:625) 
09-26 13:09:38.551: E/AndroidRuntime(25966): at dalvik.system.NativeStart.main(Native Method)

正在對以下的方法實施測定值：

listView.setOnItemClickListener(new OnItemClickListener() { 

    @Override 
    public void onItemClick(AdapterView<?> parent, View view, int position, 
      long id) { 
     // TODO Auto-generated method stub 
     int itemPostition = position; 
     String itemString = (String)parent.getItemAtPosition(position); 
     Toast.makeText(getApplicationContext(), ""+itemPostition+" "+itemString, Toast.LENGTH_SHORT).show(); 
    } 
});

79行：

String itemString = (String)parent.getItemAtPosition(position);

Java類：

public class MainActivity extends Activity { 

    ArrayList<HashMap<String, Object>> listFill; 
    ListView listView; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.activity_main); 
     listFill = new ArrayList<HashMap<String, Object>>(); 
     listView = (ListView) findViewById(R.id.listofviews); 

     // Initializing and defining the contents to be filled 
     int[] songIcons = { R.drawable.music, R.drawable.music, 
       R.drawable.music, R.drawable.music, R.drawable.music }; 
     String[] songTitle = { "Song One", "Song Two", "Song Three", 
       "Song Four", "Song Five" }; 
     String[] songDescription = { "Description One", "Description Two", 
       "Description Three", "Description Four", "Description Five" }; 

     //Looping through the contents and adding it to our ArrayList 
     for (int i = 0; i < songIcons.length; i++) { 
      HashMap<String, Object> toFill = new HashMap<String, Object>(); 
      //Filling the HashMap first 
      toFill.put("songIcon", songIcons[i]); 
      toFill.put("songTitle", songTitle[i]); 
      toFill.put("songDescription", songDescription[i]); 
      //Filling the HashMap inside the ArrayList 
      listFill.add(toFill); 
     } 

     //Creating adapter for the listView 
     ListAdapter adapter = new SimpleAdapter(MainActivity.this, listFill, 
       R.layout.custom_layout, new String[] { "songIcon", "songTitle", 
         "songDescription" }, new int[] { R.id.list_icon, 
         R.id.list_title, R.id.list_description }); 
     listView.setAdapter(adapter); 
//  setListAdapter(adapter); 

     //Implementing on itemClicked 

     listView.setOnItemClickListener(new OnItemClickListener() { 

      @Override 
      public void onItemClick(AdapterView<?> parent, View view, int position, 
        long id) { 
       // TODO Auto-generated method stub 
       int itemPostition = position; 
       String itemString = (String)parent.getItemAtPosition(position); 
       Toast.makeText(getApplicationContext(), ""+itemPostition+" "+itemString, Toast.LENGTH_SHORT).show(); 
      } 
     }); 

    }

爲什麼我得到這個錯誤？有人可以請幫助。我試圖讓ListView中的項目內容點擊

來源

2013-09-26 Rakeeb Rajbhandari

試'的HashMap <字符串，對象>地圖= HashMap中<字符串，對象> parent.getItemAtPosition（位置）' – Raghunandan

您鑄造HashMap對象爲String對象這一異常引起

來源

2013-09-26 07:35:16

這裏：

String itemString = (String)parent.getItemAtPosition(position);

什麼是返回是一個HashMap和你將它轉換爲String。

來源

2013-09-26 07:36:41 fasteque

試試這個

String i= String.valueOf(position); 
Toast.makeText(getApplicationContext(), i, Toast.LENGTH_LONG).show();

來源

2013-09-26 07:49:15 vish

由於ArrayList的listFill傳遞到您的ListView適配器，你可以得到包含標題，圖標和說明對應於被點擊的項目的位置該歌曲的HashMap對象。因此，

HashMap<String, Object> itemSong = HashMap<String, Object>parent.getItemAtPosition(position); 
String itemString = itemSong.get("SongTitle");

將符合您的要求。

來源

2013-09-26 07:49:52 ashjtech

嘗試這種

String itemString = parent.getItemAtPosition(position).toString(); 
Toast.makeText(getApplicationContext(), ""+itemPostition+" "+itemString, Toast.LENGTH_SHORT).show();

來源

2013-09-26 08:56:33

的ListView onItemClickListener

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