Remove item from custom listview on button click

问题

I have a custom listview, that has 2 textviews and 2 buttons (play and delete button) I want when I click the delete button to delete the current line.

My adapter class

import java.util.ArrayList;

import android.content.Context;
import android.graphics.Color;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.TextView;

public class SunetePreferateAdaptor extends BaseAdapter {

    class ob {
        String titlu, descriere;

        public ob(String titlu, String descriere) {
            this.titlu = titlu;
            this.descriere = descriere;
        }
    }

    ArrayList<ob> lista;
    Context context;

    public SunetePreferateAdaptor(Context context) {
        this.context = context;
        lista = new ArrayList<ob>();

        for (int i = 1; i <= 20; i++) {
            lista.add(new ob("text", "text2"));

        }

    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return lista.size();
    }

    @Override
    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return lista.get(arg0);
    }

    @Override
    public long getItemId(int arg0) {
        // TODO Auto-generated method stub
        return arg0;
    }

    @Override
    public View getView(int arg0, View arg1, ViewGroup arg2) {
        // TODO Auto-generated method stub

        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View row = inflater.inflate(R.layout.single_favsound_row, arg2, false);

        Button b2 = (Button) row.findViewById(R.id.button2);
        b2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                // here, i want to delete the current row of the listview
                //
                //
            }
        });
        TextView titlu = (TextView) row.findViewById(R.id.singleText2);
        titlu.setText(lista.get(arg0).titlu);
        titlu.setTextColor(Color.WHITE);
        titlu.setTypeface(Global.font1);
        TextView descriere = (TextView) row.findViewById(R.id.singleText1);
        descriere.setText(lista.get(arg0).descriere);
        descriere.setTextColor(Color.WHITE);
        descriere.setTypeface(Global.font1);

        return row;
    }
}

Well how can I do that? I've tried making the arraylist static and delete its items on click.. but no success..

回答1:

You need not make ArrayList static.

You need to delete the data from the list which populates listview. You call notifyDataSetChanged(); to refresh the lsitview.

You can remove the static key word and use

 Button b2 = (Button) row.findViewById(R.id.button1);
        b2.setTag(arg0); 
        b2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                int pos = (int)arg0.getTag();
                  lista.remove(pos);
                  SunetePreferateAdaptor.this.notifyDataSetChanged();            }
        });

Alternative :

You can pass the list to the constructor of adapter class.

 ListView lv = (ListView) this.findViewById(R.id.listView1);    
     ArrayList<ob> lista = new ArrayList<ob>();

        for (int i = 1; i <= 20; i++) {
            lista.add(new ob("text", "text"+i));

        }

lv.setAdapter(new SunetePreferateAdaptor(this,lista));

Then have this in a separate .java file

class ob {
    String titlu, descriere;

    public ob(String titlu, String descriere) {
        this.titlu = titlu;
        this.descriere = descriere;
    }
}

Then

public class SunetePreferateAdaptor extends BaseAdapter {


    ArrayList<ob> lista;
    Context context;

    public SunetePreferateAdaptor(Context context, ArrayList<ob> lista ) {
        this.context = context;
        this.lista= lista;

    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return lista.size();
    }

    @Override
    public Object getItem(int arg0) {
        // TODO Auto-generated method stub
        return lista.get(arg0);
    }

    @Override
    public long getItemId(int arg0) {
        // TODO Auto-generated method stub
        return arg0;
    }

    @Override
    public View getView(int arg0, View arg1, ViewGroup arg2) {
        // TODO Auto-generated method stub

        LayoutInflater inflater = (LayoutInflater) context
                .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        View row = inflater.inflate(R.layout.fg, arg2, false);

        Button b2 = (Button) row.findViewById(R.id.button1);
        b2.setTag(arg0);
        b2.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View arg0) {
                int pos = (int)arg0.getTag();
                  lista.remove(pos);
                  SunetePreferateAdaptor.this.notifyDataSetChanged();            }
        });
        TextView titlu = (TextView) row.findViewById(R.id.textView1);
        titlu.setText(lista.get(arg0).titlu);
        titlu.setTextColor(Color.WHITE);

        TextView descriere = (TextView) row.findViewById(R.id.textView2);
        descriere.setText(lista.get(arg0).descriere);


        return row;
    }
}

回答2:

try this

b2.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View arg0) {
            lista.remove(position);
            SunetePreferateAdaptor.notifyDataSetChanged();
        }
    });

回答3:

You can done it by using your ArrayList lista. First remove the item in current position and the call adapter.notifyDataSetChanged() function.

回答4:

This code worked absolutely fine for me.

public class CustomAdapter extends ArrayAdapter<String>
{
Context c1;
String s1[];
int s2[];
CustomAdapter(Context c,String s[],int s3[])
{
    super(c,R.layout.tcustom,s);
    this.c1=c;
    this.s1=s;
    this.s2=s3;
}

public View getView(int position,View v,ViewGroup parent)
{
    LayoutInflater li=(LayoutInflater) c1.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    v=li.inflate(R.layout.tcustom,null);
    TextView tv=(TextView)v.findViewById(R.id.textView);
    ImageView im=(ImageView)v.findViewById(R.id.imageview);
    tv.setText(s1[position]);
    im.setImageResource(s2[position]);

    Button bt = (Button) v.findViewById(R.id.button);
    bt.setTag(position); //important so we know which item to delete on button click

    bt.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v)
        {
            v.setVisibility(View.GONE);
            notifyDataSetChanged();


            int positionToRemove = (int)v.getTag(); //get the position of the view to delete stored in the tag
            removeItem(positionToRemove); //remove the item
        }
    });

    return v;
}

public void removeItem(int position){
    //convert array to ArrayList, delete item and convert back to array
    ArrayList<String> a = new ArrayList<>(Arrays.asList(s1));
    a.remove(position);
    String[] s = new String[a.size()];
    s=a.toArray(s);
    s1 = s;
    notifyDataSetChanged(); //refresh your listview based on new data

}
 public int getCount() {
  return s1.length;
 }
 public String getItem(int position) {
 return s1[position];
 }}

来源：https://stackoverflow.com/questions/23103356/remove-item-from-custom-listview-on-button-click