如何使用ImageAdapter从Gridview中获取所选项目？(机器人)

Question

我使用ListView来显示从数据库中检索到的一些数据(String)......非常简单,但我的一个cooworkers决定在屏幕上的文本前放置一个图像.我们无法用Listview做到这一点,但我们发现了一些GridView的示例,它看起来完全符合我们的需要,然后我们花了一些时间使用GridView并将图像放在文本的前面.

现在,遗憾的是我们不知道如何获取所选项目(基于来自所选项目的文本)

我正在使用OnItemClickListener,并且在onItemClick中使用方法gridView.getItemSelectedAtPosition(),但我得到的所有内容都是"null".

我现在不知道如果ImageAdapter与它有关,因为如果我将它改为ArrayAdapter我可以正确地获得正确的项目但是这样的行中没有图像.

gridview.setOnItemClickListener(new OnItemClickListener() {  
   public void onItemClick(AdapterView<?> parent, View v, int position, long id{     String selectedItem = (String) (gridView.getItemAtPosicion(position)); //always null     } });

我能做什么？

已编辑 - ListView来源

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;
public class ImageAdapter extends BaseAdapter {
private Context context;
private final String[] mobileValues;
private final String[] mobileValuesD;

public ImageAdapter(Context context, String[] mobileValues, String[] mobileValuesD) {
this.context = context;
this.mobileValues = mobileValues;
this.mobileValuesD = mobileValuesD;
}

  public View getView(int position, View convertView, ViewGroup parent) { 
  LayoutInflater inflater = (LayoutInflater) context.getSystemService           (Context.LAYOUT_INFLATER_SERVICE);
  View gridView;

  if (convertView == null) {

  gridView = new View(context);

   // get layout from mobile.xml
    gridView = inflater.inflate(R.layout.pesquisa_2, null);

  // set value into textview
    TextView textView = (TextView) gridView.findViewById(R.id.grid_item_label);
     textView.setText(mobileValues[position]+"\n"+mobileValuesD[position]);

 // set image based on selected text
  ImageView imageView = (ImageView) gridView.findViewById(R.id.grid_item_image);

  String mobile = mobileValues[position];

 //SELECT DAS IMAGENS

  if (mobile.equals("pdt1")) {
     imageView.setImageResource(R.drawable.img1);
  } else if (mobile.equals("prd2")) {
      imageView.setImageResource(R.drawable.feijao);
   } else {
       imageView.setImageResource(R.drawable.acucar);
    }


   } else {
    gridView = (View) convertView;
   }

    return gridView;
 }

   public int getCount() {
        return mobileValues.length;
 }

  public Object getItem(int position) {
      return null;
 }

   public long getItemId(int position) {
      return 0;
 }

 }

Answer 1

gridView.getItemAtPosition(position)getItem(int position)在场景中调用适配器- 所以getItem在你的ImageAdapter类中实现返回sth,这将允许你识别选择的内容(可能mobileValues[position]是足够的或只是你写入textview的内容:) mobileValues[position] + "\n" + mobileValuesD[position].

另一方面onItemClick(AdapterView<?> parent, View v, int position, long id)你已经拥有所选项目的位置也许它是足够的信息？你在那个听众中要做什么？

我对您的适配器进行了一些更改:

public class ImageAdapter extends BaseAdapter {

    private final String[] mobileValues;
    private final String[] mobileValuesD;

    public ImageAdapter(String[] mobileValues, String[] mobileValuesD) {
        this.mobileValues = mobileValues;
        this.mobileValuesD = mobileValuesD;
    }

    @Override
    public View getView(int position, View view, ViewGroup parent) {
        if (view == null) {
            view = ViewGroup.inflate(
                    parent.getContext(), R.layout.pesquisa_2, null);
        }

        ((TextView) view.findViewById(R.id.grid_item_label))
                .setText(getItem(position));

        ((ImageView) view.findViewById(R.id.grid_item_image))
                .setImageResource(getImageResForPosition(position));

        return view;
    }

    private int getImageResForPosition(int position) {
        String mobile = mobileValues[position];
        if (mobile.equals("pdt1")) {
            return R.drawable.img1;
        } else if (mobile.equals("prd2")) {
            return R.drawable.feijao;
        } else {
            return R.drawable.acucar;
        }
    }

    @Override
    public int getCount() {
        return mobileValues.length;
    }

    @Override
    public Object getItem(int position) {
        return mobileValues[position] + "\n" + mobileValuesD[position];
    }

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