在自定义列表视图中ArrayList对象是否重复？

我不知道我应该给这个问题什么标题，因为我的代码没有给我错误。我不知道它为什么这样表现。问题是，当我第一次点击_findButton时，它打开它获取3列表视图项目，并显示在列表中，当我点击回我想列表项目被清除，这样我再次点击_findButton它给了我相同的3 listview项目，但它给了我每个重复6项。我搜查了很多，但不知道问题在哪里。如果可以，请你帮助我。我刚来这地方。谢谢。在自定义列表视图中ArrayList对象是否重复？

package com.donateblood.blooddonation; 
 
import android.app.ProgressDialog; 
 
import android.content.Intent; 
 
import android.os.AsyncTask; 
 
import android.os.Bundle; 
 
import android.support.v7.app.AppCompatActivity; 
 
import android.view.MenuItem; 
 
import android.view.View; 
 
import android.widget.ArrayAdapter; 
 
import android.widget.Button; 
 
import android.widget.EditText; 
 
import android.widget.Spinner; 
 
import android.widget.Toast; 
 

 
import com.facebook.FacebookSdk; 
 
import com.mongodb.BasicDBObject; 
 
import com.mongodb.DB; 
 
import com.mongodb.DBCollection; 
 
import com.mongodb.DBCursor; 
 
import com.mongodb.DBObject; 
 

 
import java.util.ArrayList; 
 
import java.util.List; 
 

 
import butterknife.ButterKnife; 
 
import butterknife.InjectView; 
 

 
/** 
 
* Created by YouCaf Iqbal on 4/6/2016. 
 
*/ 
 
public class MainGUI extends AppCompatActivity { 
 
    public static ArrayList<DonorPerson> Donors = new ArrayList<DonorPerson>(); 
 
    @InjectView(R.id.findppl) Button _findButton; 
 
    GPSTracker gps; 
 
    String bloodgroup=null; 
 
    private double latitude; 
 
    private double longitude;DB db; 
 
    DBCursor cursor; 
 
    DBCollection collection; 
 
    Database dataobj = new Database(); 
 
    ArrayList allPPLlat = new ArrayList(); 
 
    ArrayList allPPLlong = new ArrayList(); 
 
    ArrayList allPPLNumbers = new ArrayList(); 
 
    ArrayList allPPLNames = new ArrayList(); 
 
    ArrayList allPPLImages = new ArrayList(); 
 
    ArrayList allPPLEmails = new ArrayList(); 
 
    public Spinner mySpinner; 
 
    @Override 
 
    public void onCreate(Bundle savedInstanceState) { 
 
     super.onCreate(savedInstanceState); 
 
     setContentView(R.layout.maingui); 
 
     ButterKnife.inject(this); 
 
     getSupportActionBar().setDisplayHomeAsUpEnabled(true); 
 
     //FacebookSdk.sdkInitialize(MainGUI.this); 
 
     Spinner spinner =(Spinner) findViewById(R.id.spinner); 
 
     String[] list = getResources().getStringArray(R.array.blood_type); 
 
     ArrayAdapter<String> adapter = new ArrayAdapter<String>(this,R.layout.spinner_layout,R.id.txt,list); 
 
     spinner.setAdapter(adapter); 
 
     _findButton.setOnClickListener(new View.OnClickListener() { 
 
      @Override 
 
      public void onClick(View v) { 
 
       getCurrentLatLong(); 
 
       dbAsync thrd = new dbAsync(); 
 
       thrd.execute(); 
 
      } 
 
      //distance=Distance(lablat, lablong, curlat, curlong); 
 
     }); 
 
    } 
 
    public void getCurrentLatLong(){ 
 
     gps = new GPSTracker(MainGUI.this); 
 
     if (gps.canGetLocation()) { 
 
      latitude = gps.getLatitude(); 
 
      longitude = gps.getLongitude(); 
 
     } 
 
    } 
 
    @Override 
 
    public boolean onOptionsItemSelected(MenuItem item) { 
 
     if(item.getItemId()==android.R.id.home){ 
 
      finish(); 
 
     } 
 
     return super.onOptionsItemSelected(item); 
 
    } 
 

 

 
    public class dbAsync extends AsyncTask<Void,Void,Void>{ 
 
     private ProgressDialog pDialog; 
 

 
     @Override 
 
     protected Void doInBackground(Void... voids) { 
 

 
      getOtherLatLong(); 
 
      return null; 
 
     } 
 

 
     @Override 
 
     protected void onPreExecute() { 
 
      super.onPreExecute(); 
 
      pDialog = new ProgressDialog(MainGUI.this); 
 
      pDialog.setMessage("Searching people nearby..."); 
 
      pDialog.setIndeterminate(false); 
 
      pDialog.setCancelable(true); 
 
      pDialog.show(); 
 
     } 
 

 
     @Override 
 
     protected void onPostExecute(Void aVoid) { 
 

 
      super.onPostExecute(aVoid); 
 
      pDialog.dismiss(); 
 
      Intent intent = new Intent(getApplicationContext(), PeopleList.class); 
 
      //intent.putExtra("DonorsList",Donors); 
 
      startActivity(intent); 
 
      // Toast.makeText(getBaseContext(), "Near by latitudes "+SelectedPPLlat, Toast.LENGTH_LONG).show(); 
 
      // Toast.makeText(getBaseContext(), "Near by longitudes "+SelectedPPLlong, Toast.LENGTH_LONG).show(); 
 
     } 
 
    } 
 

 
    public void getOtherLatLong() { 
 
     db = dataobj.getconnection(); 
 
     collection = db.getCollection("UserDetails"); 
 
     mySpinner=(Spinner) findViewById(R.id.spinner); 
 
     bloodgroup = mySpinner.getSelectedItem().toString(); 
 
     BasicDBObject whereQuery = new BasicDBObject(); 
 
     whereQuery.put("bloodgroup",bloodgroup); 
 
     cursor = collection.find(whereQuery); 
 
     while (cursor.hasNext()) { 
 
      DBObject doc = cursor.next(); 
 
      // Lats longs used in the next for Loop for calculation distances 
 
      allPPLlat.add(doc.get("lat")); 
 
      allPPLlong.add(doc.get("long")); 
 
      // All these other arraylists are used to store object of a donor person 
 
      allPPLNumbers.add(doc.get("number").toString()); 
 
      allPPLNames.add(doc.get("Name").toString()); 
 
      allPPLImages.add(doc.get("image").toString()); 
 
      allPPLEmails.add(doc.get("email").toString()); 
 

 
     } 
 
     // Clear DONOR objects before populating 
 
     //Donors.clear(); 
 
     //Donors.removeAll(Donors); 
 
     for(int i =0;i<allPPLlat.size();i++){ 
 

 
      double Dist= Distance(Double.parseDouble(allPPLlat.get(i).toString()),Double.parseDouble(allPPLlong.get(i).toString()),latitude,longitude); 
 
      Dist=Dist/1000; 
 
      if(Dist<20){ 
 
       Donors.add(new DonorPerson(""+allPPLNames.get(i)+"", ""+allPPLEmails.get(i)+"" ,""+allPPLNumbers.get(i)+"" ,""+allPPLImages.get(i)+"")); 
 
      } 
 
     } 
 
    } 
 

 
    public double Distance(double lat1, double lon1, double lat2, double lon2) { 
 
     double R = 6371.0; // km 
 
     double dLat = (lat2 - lat1) * Math.PI/180.0; 
 
     double dLon = (lon2 - lon1) * Math.PI/180.0; 
 
     lat1 = lat1 * Math.PI/180.0; 
 
     lat2 = lat2 * Math.PI/180.0; 
 

 
     double a = Math.sin(dLat/2.0) * Math.sin(dLat/2.0) + 
 
       Math.sin(dLon/2.0) * Math.sin(dLon/2.0) * Math.cos(lat1) * Math.cos(lat2); 
 
     double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1 - a)); 
 
     double d = R * c; 
 
     return d * 1000; // return distance in m 
 
    } 
 

 
    /* public ArrayList<DonorPerson> getList() { 
 
     return this.Donors; 
 
    } */ 
 
}

package com.donateblood.blooddonation; 
 

 
import android.Manifest; 
 
import android.content.Intent; 
 
import android.content.pm.PackageManager; 
 
import android.graphics.Bitmap; 
 
import android.graphics.BitmapFactory; 
 
import android.graphics.Canvas; 
 
import android.graphics.Path; 
 
import android.graphics.Rect; 
 
import android.net.Uri; 
 
import android.os.Bundle; 
 
import android.support.annotation.Nullable; 
 
import android.support.v4.app.ActivityCompat; 
 
import android.support.v7.app.AppCompatActivity; 
 
import android.util.Base64; 
 
import android.view.MenuItem; 
 
import android.view.View; 
 
import android.view.ViewGroup; 
 
import android.widget.ArrayAdapter; 
 
import android.widget.Button; 
 
import android.widget.ImageView; 
 
import android.widget.ListView; 
 
import android.widget.Toast; 
 
import java.util.ArrayList; 
 

 
/** 
 
* Created by YouCaf Iqbal on 4/30/2016. 
 
*/ 
 
public class PeopleList extends AppCompatActivity { 
 

 
    public ArrayAdapter<DonorPerson> adapter; 
 
    int count=0; 
 
    // public MainGUI mainobj; 
 
    // ArrayList<DonorPerson> Donors; 
 

 
    @Override 
 
    protected void onCreate(@Nullable Bundle savedInstanceState) { 
 
     super.onCreate(savedInstanceState); 
 
     setContentView(R.layout.peoplelistview); 
 
     getSupportActionBar().setDisplayHomeAsUpEnabled(true); 
 
     //mainobj= new MainGUI(); 
 

 
    // Donors.addAll(mainobj.getList()); 
 
     //Donors= (ArrayList<DonorPerson>)getIntent().getSerializableExtra("DonorsList"); 
 
     adapter = new MyListAdapter(); 
 
     populateListView(); 
 

 
    } 
 

 
    @Override 
 
    public boolean onOptionsItemSelected(MenuItem item) { 
 

 
     if (item.getItemId() == android.R.id.home) { 
 
      for(int i =0; i <MainGUI.Donors.size(); i++){ 
 
       MainGUI.Donors.remove(i); 
 
      } 
 
      adapter.notifyDataSetChanged(); 
 
      finish(); 
 
     } 
 
     return super.onOptionsItemSelected(item); 
 
    } 
 

 
    @Override 
 
    public void onBackPressed() 
 
    { 
 
     for(int i =0; i <MainGUI.Donors.size(); i++){ 
 
      MainGUI.Donors.remove(i); 
 
     } 
 
     adapter.notifyDataSetChanged(); 
 
     finish(); 
 
     super.onBackPressed(); 
 
    } 
 

 
    public void populateListView() { 
 
     ListView list = (ListView) findViewById(R.id.DonorsListView); 
 
     list.setAdapter(adapter); 
 
     //count = list.getAdapter().getCount(); 
 
    } 
 

 
    public class MyListAdapter extends ArrayAdapter<DonorPerson> { 
 

 
     ArrayList allPPLNumbers = new ArrayList(); 
 

 
     public MyListAdapter() { 
 
      super(PeopleList.this, R.layout.singlelistitemview, MainGUI.Donors); 
 
     } 
 

 
     @Override 
 
     public View getView(final int position, View convertView, ViewGroup parent) { 
 
      ViewHolder MainViewHolder = null; 
 
      View itemView = convertView; 
 
      if (itemView == null) { 
 
       itemView = getLayoutInflater().inflate(R.layout.singlelistitemview, parent, false); 
 
       ViewHolder viewHolder = new ViewHolder(); 
 

 
       // Find the Donor to work with. 
 
       DonorPerson currentPerson = MainGUI.Donors.get(position); 
 
       allPPLNumbers.add(currentPerson.getNumber()); 
 
       //Set the Image of the Current Donor 
 
       viewHolder.DonorImage = (ImageView) itemView.findViewById(R.id.image); 
 
       //currentPerson.getImage(); 
 
       byte[] decodedString = Base64.decode(currentPerson.getImage(), Base64.DEFAULT); 
 
       Bitmap decodedByte = BitmapFactory.decodeByteArray(decodedString, 0, decodedString.length); 
 

 
       Bitmap decodedFinalImage = getRoundedShape(decodedByte); 
 
       //Bitmap RoundedImage = getRoundedShape(ImageBitmap); 
 

 
       viewHolder.DonorImage.setImageBitmap(decodedFinalImage); 
 
       viewHolder.CallBtn = (Button) itemView.findViewById(R.id.buttonCall); 
 

 
       viewHolder.CallBtn.setOnClickListener(new View.OnClickListener() { 
 
        @Override 
 
        public void onClick(View v) { 
 
         String number = (String) allPPLNumbers.get(position); 
 
         Intent intent = new Intent(Intent.ACTION_CALL); 
 
         intent.setData(Uri.parse("tel:" + number)); 
 
         if (ActivityCompat.checkSelfPermission(PeopleList.this, Manifest.permission.CALL_PHONE) != PackageManager.PERMISSION_GRANTED) { 
 
          // TODO: Consider calling 
 
          // ActivityCompat#requestPermissions 
 
          // here to request the missing permissions, and then overriding 
 
          // public void onRequestPermissionsResult(int requestCode, String[] permissions, 
 
          //           int[] grantResults) 
 
          // to handle the case where the user grants the permission. See the documentation 
 
          // for ActivityCompat#requestPermissions for more details. 
 
          return; 
 
         } 
 
         startActivity(intent); 
 
        } 
 
       }); 
 

 
       viewHolder.MsgBtn = (Button) itemView.findViewById(R.id.buttonMsg); 
 
       viewHolder.MsgBtn.setOnClickListener(new View.OnClickListener() { 
 
        @Override 
 
        public void onClick(View v) { 
 
         String number = (String) allPPLNumbers.get(position); 
 
         Uri uri = Uri.parse("smsto:" + number); 
 
         Intent intent = new Intent(Intent.ACTION_SENDTO, uri); 
 
         intent.putExtra("sms_body",""); 
 
         startActivity(intent); 
 
        } 
 
       }); 
 

 
       viewHolder.NotifyBtn = (Button) itemView.findViewById(R.id.buttonNotify); 
 
       viewHolder.NotifyBtn.setOnClickListener(new View.OnClickListener() { 
 
        @Override 
 
        public void onClick(View v) { 
 
         Toast.makeText(getBaseContext(), "Notify Clicked", Toast.LENGTH_LONG).show(); 
 

 
        } 
 
       }); 
 

 
       itemView.setTag(viewHolder); 
 
      } 
 
      else{ 
 
       MainViewHolder= (ViewHolder) itemView.getTag(); 
 
      } 
 
      return itemView; 
 

 
     } 
 

 

 
     public Bitmap getRoundedShape(Bitmap scaleBitmapImage) { 
 
      int targetWidth = 200; 
 
      int targetHeight = 200; 
 
      Bitmap targetBitmap = Bitmap.createBitmap(targetWidth, 
 
        targetHeight,Bitmap.Config.ARGB_8888); 
 

 
      Canvas canvas = new Canvas(targetBitmap); 
 
      Path path = new Path(); 
 
      path.addCircle(((float) targetWidth - 1)/2, 
 
        ((float) targetHeight - 1)/2, 
 
        (Math.min(((float) targetWidth), 
 
          ((float) targetHeight))/2), 
 
        Path.Direction.CCW); 
 

 
      canvas.clipPath(path); 
 
      Bitmap sourceBitmap = scaleBitmapImage; 
 
      canvas.drawBitmap(sourceBitmap, 
 
        new Rect(0, 0, sourceBitmap.getWidth(), 
 
          sourceBitmap.getHeight()), 
 
        new Rect(0, 0, targetWidth, targetHeight), null); 
 
      return targetBitmap; 
 
     } 
 
    } 
 
     public class ViewHolder { 
 

 
      ImageView DonorImage; 
 
      Button CallBtn; 
 
      Button MsgBtn; 
 
      Button NotifyBtn; 
 
     } 
 
    }

来源

2016-05-14 Yousaf Iqbal

Yosuf，不要指望我们读这一堆代码，并试图找出什么是破碎的。你甚至尝试调试吗？使用LogCat消息？是否需要复制所有代码？ – UDKOX

您似乎已注释掉清单的代码。这是问题的原因吗？（在第一个文件中，靠近'getOtherLatLong'方法的末尾）。它需要说'Donors.clear（）;' – 4castle

https://stackoverflow.com/help/mcve请！ – Lee

我认为，问题是，你不清除的ArrayList，对于您的ListView提供的值。要清除ArrayList，只需使用arrayList.clear();
将此代码放入您的onCreate方法中即可，用于您的MainGUI类。如果你清除你的ArrayList，你的应用程序应该能够正常工作。

来源

2016-05-15 00:14:35 AkashBhave

我试过但它不工作:-( –

为什么不尝试清除'String [] list'？ – AkashBhave

在自定义列表视图中ArrayList对象是否重复？

回答

相关问题