Wie überprüft man, ob die ListView leer ist oder nicht benutzerdefinierten Listenadapter verwendet

Question

Ich habe zwei Adpater in meiner App verwendet, einen für Offline-Modus, der die Daten von einem lokalen SQLite DB holt. Der zweite Adapter holt Daten vom Server und zeigt die Elemente in der Listenansicht, die beiden Adaptern gemeinsam ist. Es gibt keine Daten in der Liste Ich habe die leere Ansicht verwendet, um anzuzeigen, dass die Liste leer ist. Aber selbst wenn es Daten in der SQLite gibt, zeigt es mir die Liste leer. Ich würde gerne wissen, gibt es eine Möglichkeit zu überprüfen, ob der Adapter null ist oder nicht. Wenn es nicht null ist, bedeutet dies, dass es die Werte in der Liste anzeigen sollte.

Offline-Adapter:

public class ImageListAdapter extends BaseAdapter { 
    Context context; 
    ArrayList<ImagelistItems> imageList; 

    public ImageListAdapter(Context context, ArrayList<ImagelistItems> list) { 

     this.context = context; 
     imageList = list; 
    } 


    @Override 
    public int getCount() { 

     return imageList.size(); 
    } 

    @Override 
    public Object getItem(int position) { 

     return imageList.get(position); 
    } 

    @Override 
    public long getItemId(int position) { 

     return position; 
    } 

    @Override 
    public View getView(int position, View convertView, ViewGroup arg2) { 
     ImagelistItems imagelistItems = imageList.get(position); 

     if (convertView == null) { 
      LayoutInflater inflater = (LayoutInflater) context 
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      convertView = inflater.inflate(R.layout.imagelist_items, null); 

     } 
     byte[] outImage = imagelistItems.getImage(); 
     ByteArrayInputStream imageStream = new ByteArrayInputStream(outImage); 
     final Bitmap theImage = BitmapFactory.decodeStream(imageStream); 
     ImageView img = (ImageView) convertView.findViewById(R.id.imgview); 
     img.setImageBitmap(theImage); 
     final TextView merchname = (TextView) convertView.findViewById(R.id.lsmerchantname); 
     merchname.setText(imagelistItems.getMerchantname()); 
     final TextView paid = (TextView) convertView.findViewById(R.id.lspaiddate); 
     paid.setText(imagelistItems.getPaidon()); 
     TextView status = (TextView) convertView.findViewById(R.id.lsstatus); 
     status.setText(imagelistItems.getStatus()); 
     final TextView amt = (TextView) convertView.findViewById(R.id.lsamount); 
     amt.setText(imagelistItems.getAmount()); 
     ImageButton oofbutton = (ImageButton) convertView.findViewById(R.id.btnofflinebutton); 
     oofbutton.setVisibility(View.INVISIBLE); 
     final TextView category = (TextView) convertView.findViewById(R.id.lscategory); 
     category.setText(imagelistItems.getCategory()); 
     final TextView paymode = (TextView) convertView.findViewById(R.id.lspaidwith); 
     paymode.setText(imagelistItems.getPaymmode()); 
     final TextView comment = (TextView) convertView.findViewById(R.id.lscomment); 
     comment.setText(imagelistItems.getComment()); 
     final TextView moneydet = (TextView) convertView.findViewById(R.id.moneydetails); 
     final String moen; 
     CurrenctSession currenctSession = new CurrenctSession(context); 
     if (currenctSession.isLoggedIn()) { 
      HashMap<String, String> cur = currenctSession.getUserDetails(); 
      moen = cur.get(currenctSession.KEY_CURRENCY); 
      moneydet.setText(moen); 
     } else { 
      moneydet.setVisibility(View.INVISIBLE); 
     } 
     convertView.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       String am = amt.getText().toString(); 
       if (am.contains("km") | am.contains("m")) { 
        Intent i = new Intent(context, MapsDetailPage.class); 
        i.putExtra("distance", amt.getText().toString()); 
        i.putExtra("origin", merchname.getText().toString()); 
        i.putExtra("dest", paymode.getText().toString()); 
        i.putExtra("catg", category.getText().toString()); 
        i.putExtra("pdate", paid.getText().toString()); 
        i.putExtra("comm", comment.getText().toString()); 
        context.startActivity(i); 
       } else { 
        Intent i = new Intent(context, DetailsPage.class); 
        i.putExtra("bitmap", theImage); 
        i.putExtra("amount", amt.getText().toString()); 
        i.putExtra("mername", merchname.getText().toString()); 
        i.putExtra("paidon", paid.getText().toString()); 
        i.putExtra("catg", category.getText().toString()); 
        i.putExtra("paym", paymode.getText().toString()); 
        i.putExtra("comm", comment.getText().toString()); 
        context.startActivity(i); 
       } 

      } 
     }); 
     return convertView; 

    } 
} 

Online Adapter:

public class CustomlistJsonadapter extends BaseAdapter { 

    private Activity activity; 
    private LayoutInflater inflater; 
    private List<ReceiptMov> movieItems; 


    public CustomlistJsonadapter(Activity activity, List<ReceiptMov> movieItems) { 
     this.activity = activity; 
     this.movieItems = movieItems; 
    } 

    @Override 
    public int getCount() { 
     return movieItems.size(); 
    } 

    @Override 
    public Object getItem(int location) { 
     return movieItems.get(location); 
    } 

    @Override 
    public long getItemId(int position) { 
     return position; 
    } 

    @Override 
    public View getView(int position, View convertView, ViewGroup parent) { 

     if (inflater == null) 
      inflater = (LayoutInflater) activity 
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
     if (convertView == null) 
      convertView = inflater.inflate(R.layout.onlineimagelist_items, null); 

     final TextView merchantname = (TextView) convertView.findViewById(R.id.olsmerchantname); 
     final TextView paiddate = (TextView) convertView.findViewById(R.id.olspaiddate); 
     final TextView amounts = (TextView) convertView.findViewById(R.id.olsamount); 
     final TextView paidwith = (TextView) convertView.findViewById(R.id.olspaidwith); 
     final TextView categ = (TextView) convertView.findViewById(R.id.olscategory); 
     final TextView comment = (TextView) convertView.findViewById(R.id.olscomment); 
     final TextView stast = (TextView) convertView.findViewById(R.id.olsstatus); 

     ImageView imgview = (ImageView) convertView.findViewById(R.id.oimgview); 
     ReceiptMov m = movieItems.get(position); 


     // Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length); 
     byte[] s = m.getMimage(); 
     ByteArrayInputStream imageStream = new ByteArrayInputStream(s); 
     final Bitmap theImage = BitmapFactory.decodeStream(imageStream); 
     // Bitmap bm = BitmapFactory.decodeByteArray(s, 0 ,s.length); 

     imgview.setImageBitmap(theImage); 
     merchantname.setText(m.getMerchantname()); 
     paiddate.setText("Paid on:" + m.getMerdate()); 
     amounts.setText(m.getMeramount()); 
     paidwith.setText(m.getMerpaid()); 
     categ.setText(m.getMercategory()); 
     comment.setText(m.getMecomment()); 
     stast.setText("Status: " + "Uploaded"); 
     final TextView moneydet = (TextView) convertView.findViewById(R.id.omoneydetails); 
     final String moen; 
     CurrenctSession currenctSession = new CurrenctSession(activity); 
     if (currenctSession.isLoggedIn()) { 
      HashMap<String, String> cur = currenctSession.getUserDetails(); 
      moen = cur.get(currenctSession.KEY_CURRENCY); 
      moneydet.setText(moen); 
     } else { 
      moneydet.setVisibility(View.INVISIBLE); 
     } 
     convertView.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View view) { 
       String am = amounts.getText().toString(); 
       if (am.contains("km") | am.contains("m")) { 
        Intent i = new Intent(activity, MapsDetailPage.class); 
        i.putExtra("distance", amounts.getText().toString()); 
        i.putExtra("origin", merchantname.getText().toString()); 
        i.putExtra("dest", paidwith.getText().toString()); 
        i.putExtra("catg", categ.getText().toString()); 
        i.putExtra("pdate", paiddate.getText().toString()); 
        i.putExtra("comm", comment.getText().toString()); 
        activity.startActivity(i); 
       } else { 
        Intent i = new Intent(activity, DetailsPage.class); 
        i.putExtra("bitmap", theImage); 
        i.putExtra("amount", amounts.getText().toString()); 
        i.putExtra("mername", merchantname.getText().toString()); 
        i.putExtra("paidon", paiddate.getText().toString()); 
        i.putExtra("catg", categ.getText().toString()); 
        i.putExtra("paym", paidwith.getText().toString()); 
        i.putExtra("comm", comment.getText().toString()); 
        activity.startActivity(i); 
       } 

      } 
     }); 

     return convertView; 
    } 
} 

Liste:

if(imageListAdapter!=null){ 
     DatabaseHandler db = new DatabaseHandler(getApplicationContext()); 

     // Spinner Drop down elements 
     // List<String> lables = db.getAllLabels(); 
     ArrayList<ImagelistItems> list = new ArrayList<ImagelistItems>(); 
     list = db.getAllLabels(); 
     imageListAdapter = new ImageListAdapter(
       ListMode.this, list); 
     if (loginSession.isLoggedIn()) { 
      loginSession.checkLogin(); 
      listView.setAdapter(imageListAdapter); 
      // listView.setEmptyView(findViewById(R.id.empty)); 

      Toast.makeText(getApplicationContext(), db.getSyncStatus(), Toast.LENGTH_LONG).show(); 
     } else { 
      Intent i = new Intent(ListMode.this, LoginPAge.class); 
      startActivity(i); 
      ListMode.this.finish(); 
     } 

    }else{ 
     listView.setEmptyView(findViewById(R.id.empty)); 
    } 

Answer 1

Verwenden getcount() kennen die Anzahl der Elemente

if(adapter.getCount()>0) 
{ 
//some rows of listview 
} 
else 
{ 
//listview is empty 
} 

Hoffe, dass es dies dank

Answer 2

Versuchen hilft, können Sie helfen

ImageListAdapter imageListAdapter= new ImageListAdapter(); 
    listviewObject.setAdapter(imageListAdapter); 

    if (imageListAdapter!= null) 
     if (imageListAdapter.getCount() > 0){ 
      // implement your work 
     }else { 
      // do whatever you want on empty list adapter 
     } 

Answer 3

if (adapter!=null) { 
    if (adapter.getCount() > 0) { 
     // listView not empty 
    } else { 
     // listView empty 
    } 
} 

Answer 4

Setzen Sie einfach die emptyView bevor die adapter auf Listenansicht einstellen. Keine Überprüfung, ob der Adapter leer ist, listview kümmert sich darum.

Sie Code sollte wie folgt aussehen:

TextView empty = (TextView) findViewById(android.R.id.empty); 
listView.setEmptyView(empty); 
listView.setAdapter(adapter); 

Answer 5

Der folgende Code für mich gearbeitet:

list_view.setAdapter(adapter); 
if (adapter.getCount() > 0) { 

} else { 
    Toast.makeText(getApplicationContext(), "NO Data Available..", Toast.LENGTH_SHORT).show(); 
}