ADAPTER CLASS

Question

虽然有很多关于适配器的问题，但我已经阅读了所有问题，但我的问题没有解决。我有一个基本适配器，我从控制台一次更新了我的适配器我可以看到它每次调用getView时都在调用notifyDatasetChanged()。但是我的onclick()还没有更改视图项.......看起来问题出在我分配给列表的位置编号

ADAPTER CLASS

package com.bisota.utility;

import java.util.ArrayList;

import com.bisota.R;
import com.bisota.activity.Home;
import com.bisota.model.Task;

import android.app.Activity;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.BaseAdapter;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.ListView;
import android.widget.TextView;

public class ListViewAdapter extends BaseAdapter{

    private final Home context;
    private LayoutInflater inflater;
    private int position;
    private ListView mListView;
    private ArrayList<Task> tasks;

    public ListViewAdapter(Home context,ArrayList<Task> tasks) {
        super();
        this.context=context;
        inflater = LayoutInflater.from(this.context);
        this.position=0;
        this.mListView=mListView;
        this.tasks=tasks;
    }



    private static class ViewHolder {

        ImageView vendor;
        ImageButton accept;
        ImageButton reject;
        TextView date;
        TextView time;
        TextView companyName;
        TextView taskName;
        TextView taskType;
        TextView description;
        TextView status;
        int position;
    }

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

        System.out.println("GET VIEW");

         ViewHolder viewHolder = null;

         if(convertView == null) {

                convertView = inflater.inflate(R.layout.task_item_layout,null);

                viewHolder = new ViewHolder();
                viewHolder.vendor = (ImageView)convertView.findViewById(R.id.vendor);
                viewHolder.accept = (ImageButton)convertView.findViewById(R.id.yes);
                viewHolder.reject = (ImageButton)convertView.findViewById(R.id.no);
                viewHolder.date = (TextView) convertView.findViewById(R.id.date);
                viewHolder.time = (TextView) convertView.findViewById(R.id.time);
                viewHolder.companyName = (TextView) convertView.findViewById(R.id.companyName);
                viewHolder.taskName = (TextView) convertView.findViewById(R.id.taskName);
                viewHolder.taskType = (TextView) convertView.findViewById(R.id.taskType);
                viewHolder.description = (TextView) convertView.findViewById(R.id.description);
                viewHolder.status=(TextView)convertView.findViewById(R.id.responseMsg);
                viewHolder.position=0;


                convertView.setTag(viewHolder);

            }
         else
         {
            viewHolder = (ViewHolder)convertView.getTag();
         }

         Resources resources = this.context.getResources();

         if(Home.taskObjList.get(position).providerType.Facebook==true)
         {
             System.out.println("facebook");    

             viewHolder.vendor.setImageDrawable(resources.getDrawable(R.drawable.facebook));


         }
         else if(Home.taskObjList.get(position).providerType.Twitter==true)
         {
             System.out.println("twitter"); 
             viewHolder.vendor.setImageDrawable(resources.getDrawable(R.drawable.twitter));

         }

         //another section
         if(tasks.get(position).status.accepted==true)
          {
               System.out.println("A");

               //viewHolder.accept.setImageResource(R.drawable.yes);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Accepted");
               viewHolder.status.setTextColor(Color.parseColor("#006600"));



           }
           else if(tasks.get(position).status.rejected==true)
           {
               System.out.println("R"); 
              // viewHolder.reject.setImageResource(R.drawable.no);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Rejected");
               viewHolder.status.setTextColor(Color.RED);
              // notifyDataSetChanged();
           }
           else
           {
               System.out.println("N"); 
               viewHolder.status.setVisibility(View.GONE);
               viewHolder.reject.setVisibility(View.VISIBLE);
               viewHolder.accept.setVisibility(View.VISIBLE);
              // viewHolder.accept.setImageResource(R.drawable.yes);
              // viewHolder.reject.setImageResource(R.drawable.no);

           }


           String arrayString[] = tasks.get(position).startDate.toString().split("\\s+");
           viewHolder.date.setText(arrayString[0].toString());
           viewHolder.time.setText(arrayString[1].toString());
           //viewHolder.companyName.setText(Home.taskObjList.get(position).companyName.toString());
           viewHolder.taskName.setText(tasks.get(position).taskName.toString());
           viewHolder.description.setText(tasks.get(position).description.toString());
           //viewHolder.taskType.setText(Home.taskObjList.get(position).task.toString());


            //viewHolder.category.setText(events.get(position).getCategory());

          this.position=position;

           viewHolder.accept.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v){
                // TODO Auto-generated method stub
                System.out.println("accept clicked");
                tasks.get(ListViewAdapter.this.position).status.accepted=true;
                ListViewAdapter.this.notifyDataSetChanged();
            }
           });


           viewHolder.reject.setOnClickListener(new OnClickListener() {

                @Override
                public void onClick(View v){
                    // TODO Auto-generated method stub
                    System.out.println("reject clicked");
                    tasks.get(ListViewAdapter.this.position).status.rejected=true;
                    ListViewAdapter.this.notifyDataSetChanged();
                }
               });



            return convertView;



    }

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

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

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }

    private void updateItemAtPosition(int position) {
        int visiblePosition = mListView.getFirstVisiblePosition();
        View view = mListView.getChildAt(position - visiblePosition);
        mListView.getAdapter().getView(position, view, mListView);
    }

}

但我的目的是通过检查适配器中的if-else来改变按钮视图：

 if(tasks.get(position).status.accepted==true)
          {
               System.out.println("A");

               //viewHolder.accept.setImageResource(R.drawable.yes);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Accepted");
               viewHolder.status.setTextColor(Color.parseColor("#006600"));



           }
           else if(tasks.get(position).status.rejected==true)
           {
               System.out.println("R"); 
              // viewHolder.reject.setImageResource(R.drawable.no);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Rejected");
               viewHolder.status.setTextColor(Color.RED);
              // notifyDataSetChanged();
           }
           else
           {
               System.out.println("N"); 
               viewHolder.status.setVisibility(View.GONE);
               viewHolder.reject.setVisibility(View.VISIBLE);
               viewHolder.accept.setVisibility(View.VISIBLE);
              // viewHolder.accept.setImageResource(R.drawable.yes);
              // viewHolder.reject.setImageResource(R.drawable.no);

           }

更新

好像我的问题不在notifyDatasetChanged或视图中，问题在于我提供给我的列表中的位置编号。如何检索该特定行的位置编号？

Answer 1

首先做

viewHolder.status.setVisibility(View.GONE);
viewHolder.reject.setVisibility(View.GONE);
viewHolder.accept.setVisibility(View.GONE);

然后编写可见性逻辑

if(tasks.get(position).status.accepted==true)
          {
               System.out.println("A");

               //viewHolder.accept.setImageResource(R.drawable.yes);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Accepted");
               viewHolder.status.setTextColor(Color.parseColor("#006600"));



           }
           else if(tasks.get(position).status.rejected==true)
           {
               System.out.println("R"); 
              // viewHolder.reject.setImageResource(R.drawable.no);
               viewHolder.reject.setVisibility(View.GONE);
               viewHolder.accept.setVisibility(View.GONE);
               viewHolder.status.setVisibility(View.VISIBLE);
               viewHolder.status.setText("Rejected");
               viewHolder.status.setTextColor(Color.RED);
              // notifyDataSetChanged();
           }
           else
           {
               System.out.println("N"); 
               viewHolder.status.setVisibility(View.GONE);
               viewHolder.reject.setVisibility(View.VISIBLE);
               viewHolder.accept.setVisibility(View.VISIBLE);
              // viewHolder.accept.setImageResource(R.drawable.yes);
              // viewHolder.reject.setImageResource(R.drawable.no);

           }

Answer 2

您不应在适配器本身上实现onClick()方法。同样应该在它之外调用notifyDataSetChanged()。请在此处查看此示例：

How to correctly implement BaseAdapter.notifyDataSetChanged() in Android

NotifyDatasetChanged（）正在调用getView但是视图没有改变

ADAPTER CLASS

更新

2 个答案: