Listview在刷新时显示重复数据

Question

我制作了一张listview图片和文字作为元素。如果数据是文本，则显示文本，如果是图像则显示图像。

当我点击从MainActivity到列表视图的按钮时，列表视图会根据需要显示，即图像和文本数据的图像。

打开listview活动并在db中插入任何新数据并刷新listview时，会出现问题。视图中的数据完全搞砸了。它在一些文本数据中显示图像。

但是当我回到主要活动并再次回到listview时，一切都很完美。

任何人都可以帮我解决这里出错的问题。

我正在使用SimpleCursorAdaptor，CursorLoader。

MainActivity.java

public class MainActivity extends ActionBarActivity implements LoaderCallbacks<Cursor>{

private TextView from, data;

 private SimpleCursorAdapter dataAdapter;

 private String TO_USER;
 ConnectionService  connService;
 boolean mBounded;  

 @Override
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
String[] projection = {MessageHelper.COLUMN_ID,
        MessageHelper.COLUMN_FROM,
            MessageHelper.COLUMN_DATA};
    String args[] ={ "cid","data"};
        CursorLoader cursorLoader = new CursorLoader(this,
            MyContentProvider.CONTENT_URI, projection,   
                    MessageHelper.COLUMN_CONVERSATION_ID + " = ?" + " AND " + 
                    MessageHelper.COLUMN_EXIN + " =  ?" ,args, 
                    MessageHelper.COLUMN_RECIEVED_TIMESTAMP);
              return cursorLoader;
}
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setListAdapter();
     getLoaderManager().initLoader(0, null, this);
}



private void setListAdapter() {
     String[] columns = new String[] {
                MessageHelper.COLUMN_FROM,
                MessageHelper.COLUMN_DATA
              };

              int[] to = new int[] {
                R.id.data
               };

              Cursor cursor = loadMessage();
              cursor.moveToFirst();
              dataAdapter = new CustomCursorAdapter(
                        this,
                        R.layout.linear_listitem,
                        cursor,
                        columns,
                        to,
                        0);

              listview.setAdapter(dataAdapter);
.

}


public void onLoaderReset(Loader<Cursor> loader) {
     dataAdapter.swapCursor(null);
}

 protected void onResume() {
  super.onResume();
  getLoaderManager().restartLoader(0, null, this);
 }

 protected void onRestart(){
     super.onRestart();
    }

CursorAdapter.java

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLConnection; 
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;

import android.content.Context;
import android.database.Cursor;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ClipDrawable;
import android.net.Uri;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CursorAdapter;
import android.widget.ImageView;
import android.widget.RelativeLayout;
//import android.widget.LinearLayout.LayoutParams;
import android.widget.RelativeLayout.LayoutParams;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;

import com.expert.sqllite.MessageChat;
import com.expert.sqllite.MessageHelper;

public class CustomCursorAdapter extends SimpleCursorAdapter {
private LayoutInflater mInflater;
private Map<Integer, ArrayList<MessageChat>> chatMapConId = new HashMap<Integer, 

ArrayList<MessageChat>>();  
public CustomCursorAdapter(Context context, int layout, Cursor c, String[] from,          int[] to, int flags) {
    super(context, layout, c, from, to,flags);
    mInflater = (LayoutInflater)context.getSystemService

(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public void bindView(View view, Context context, Cursor cursor) {



    MessageChat msgchat = new MessageChat();
       msgchat.setData(cursor.getString(cursor.getColumnIndex(MessageHelper.COLUMN_DATA)));
      msgchat.setFrom(cursor.getString(cursor.getColumnIndex(MessageHelper.COLUMN_FROM)));


    ViewHolder  holder;
    if(!msgchat.getData().contains("-image-")){

            holder = (ViewHolder) view.getTag();

    }
    else{
        holder = (ViewHolder) view.getTag();

    }


            TextView dataMsg =(TextView)view.findViewById(R.id.data);
         RelativeLayout.LayoutParams lp1 = new RelativeLayout.LayoutParams 

(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);

            ImageView imgMsg =null;



            if(msgchat.getFrom().equalsIgnoreCase("me"))
            {

                if(!msgchat.getData().contains("-image-")){
                    dataMsg.setBackgroundResource

(R.drawable.speech_bubble_green);
                    dataMsg.setText(msgchat.getData());

                }
                else
                {
                    String[]         imageSplit=msgchat.getData().split("-image-");
                    Uri imgUri=Uri.parse(imageSplit[1]);
                    try {
                        imgMsg (ImageView)view.findViewById

(R.id.chat_image);
                        imgMsg.setImageBitmap(getThumbnail

(imgUri,context));




                              dataMsg.setVisibility(View.INVISIBLE);
                    } catch (FileNotFoundException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }
                }


                lp1.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
            }

            else
            {

                if(!msgchat.getData().contains("-image-")){
                    dataMsg.setBackgroundResource

(R.drawable.speech_bubble_orange);
                    dataMsg.setText(msgchat.getData());
                }
                else{
                    String[]   imageSplit=msgchat.getData().split("-image-");
                    Uri imgUri=Uri.parse(imageSplit[1]);
                    try {
                        imgMsg =(ImageView)view.findViewById

(R.id.chat_image);
                        imgMsg.setImageBitmap(getThumbnail

(imgUri,context));
                        imgMsg.setBackgroundResource

(R.drawable.speech_bubble_orange);
                    dataMsg.setVisibility(View.INVISIBLE);

                    } catch (FileNotFoundException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    } catch (IOException e) {
                        // TODO Auto-generated catch block
                        e.printStackTrace();
                    }

                }
                lp1.addRule(RelativeLayout.ALIGN_PARENT_LEFT);

            }

            if(!msgchat.getData().contains("-image-")){
            dataMsg.setLayoutParams(lp1);
            dataMsg.setTextColor(R.color.textColor);
            }
            else{
                imgMsg.setLayoutParams(lp1);
            }



}



@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
    // TODO Auto-generated method stub
    File imageFile;
    View rowView = mInflater.inflate(R.layout.linear_listitem, parent, false);

    View rowViewImage = mInflater.inflate(R.layout.linear_listitem_image,  parent, false);
    ViewHolder holder = null;
    ViewHolderImage holderImage = null;

    String data = cursor.getString(cursor.getColumnIndex(MessageHelper.COLUMN_DATA));
    String path = null;
    if(data.contains("-image-")){
    path = data.split("-image-")[1];
    }

        holder = new ViewHolder();

           holder.data = (TextView)rowView.findViewById(R.id.data);
           holder.imageHolder =   (ImageView)rowViewImage.findViewById(R.id.chat_image);
            rowView.setTag(holder);
            return rowView;

    }

class ViewHolder
{   
    TextView data,from;
    ImageView imageHolder ;
}
class ViewHolderImage
{   
    ImageView imageHolder ;
}

public static Bitmap getThumbnail(Uri uri,Context context) throw    FileNotFoundException,IOException{
    InputStream input = context.getContentResolver().openInputStream(uri);

    BitmapFactory.Options onlyBoundsOptions = new BitmapFactory.Options();
    onlyBoundsOptions.inJustDecodeBounds = true;
    onlyBoundsOptions.inDither=true;//optional
    onlyBoundsOptions.inPreferredConfig=Bitmap.Config.ARGB_8888;//optional
    BitmapFactory.decodeStream(input, null, onlyBoundsOptions);
    input.close();
    if ((onlyBoundsOptions.outWidth == -1) || (onlyBoundsOptions.outHeight == -1))
        return null;

    int originalSize = (onlyBoundsOptions.outHeight > onlyBoundsOptions.outWidth) ? 

onlyBoundsOptions.outHeight : onlyBoundsOptions.outWidth;

   // double ratio = (originalSize > THUMBNAIL_SIZE) ? (originalSize / THUMBNAIL_SIZE):   1.0;
    double ratio = 1.0;
    BitmapFactory.Options bitmapOptions = new BitmapFactory.Options();
    //bitmapOptions.inSampleSize = getPowerOfTwoForSampleRatio(ratio);
    bitmapOptions.inSampleSize = 2;

    bitmapOptions.inMutable = true;
    bitmapOptions.inDither=true;//optional
    bitmapOptions.inPreferredConfig=Bitmap.Config.RGB_565;//optional
    bitmapOptions.outHeight=150;
    bitmapOptions.outWidth=150;
    input = context.getContentResolver().openInputStream(uri);
    Bitmap bitmap = BitmapFactory.decodeStream(input, null, bitmapOptions);
    input.close();
    //bitmap.setWidth(400);
    //bitmap.setHeight(400);
    return bitmap;
}

private static int getPowerOfTwoForSampleRatio(double ratio){
    int k = Integer.highestOneBit((int)Math.floor(ratio));
    if(k==0) return 1;
    else return k;
}

}

更新 如果我只有数据文本或只有图像。然后列表视图是完美的。我认为问题在于视图，即文本和图像都出现在图片中。

Answer 1

    @Override
public int getItemViewType(int position) {
    Cursor cursor = (Cursor) getItem(position);
    return getItemViewType(cursor);
}

@Override
public int getViewTypeCount() {
    return 2;
}

这些方法解决了显示不当的问题