Question

我用“ListView”来显示从数据库中检索到的一些数据(String)...很简单,但我的一位同事决定将一个图像放在屏幕的文本前面。我们无法用“ListView”做到这一点,但我们找到了一些GridView的例子,这个例子与我们需要的一模一样,然后我们用GridView(GridView)用了一些时间,把图像放在文本前面。

现在,不幸的是,我们不知道如何获得选中的项目(基于选定项目产生的文本)

我使用OnTroundClickListener, 并在项目ClickFlick这个方法网格里View. Get TroupsSeabectAtPostion (), 但我得到的只是“Null”。

如果图像设计师和它有什么关系, 我现在不这样做, 因为如果我把它换成一个阵列设计师......我可以正确得到正确的项目......但是在行里没有这样的图像。

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

我能怎么办?

编辑编辑 - 列表查看源

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]+"
"+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) calls the adapter s getItem(int position) under the scene - so implement getItem in your ImageAdapter class to return sth that will allow you to identify what is selected (maybe mobileValues[position] is enough or just what you write into textview: mobileValues[position] + " " + mobileValuesD[position]).

在 onTroundClick( AdapterView<?? & gt; 父、 view v、 int 位置、 long id) 的另一方面, 您已经具备了所选项目的位置, 也许足够信息吗? 您将在听众中做什么?

我对你的适应器做了一些修改:

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] + "
" + mobileValuesD[position];
    }

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

友情链接