如何使用默认值在GridView中设置第一项，并根据JSON结果填充其余项目 [英] How to set the first item in GridView with default value and populate the rest of the items based on JSON result

问题描述

你好，我想设置我的GridView的第一个项目的默认值，并相应地填充项目的其余部分（基于JSON结果）

我的代码由2个类组成
1. MainActivity
2. GridView适配器

以下是我的GridAdapter的代码

  public class ContactGridAdapter extends ArrayAdapter< Person> {
 ***一些初始化*** 
 
 public ContactGridAdapter（上下文上下文，ArrayList< Person>值）{
 super（context，R.layout.grid_item_text）; 
 mContext = context; 
 mList = values; 
} 
 
 @Override 
 public int getCount（）{
 // TODO自动生成的方法存根
返回mList.size（）; 
 
 $ b @Override 
 public Person getItem（int position）{
 // TODO自动生成的方法存根
 return mList.get（position） ; 
} 
 
 @Override 
 public long getItemId（int position）{
 // TODO自动生成的方法存根
 return 0; 
 
 $ b @Override 
 public View getView（int position，View convertView，ViewGroup parent）{
 // TODO自动生成的方法存根
 
 LayoutInflater inflater =（LayoutInflater）mContext 
 .getSystemService（Context.LAYOUT_INFLATER_SERVICE）; 
 
查看视图; 
 
 if（convertView == null）{
 view = new View（mContext）; 
 view = inflater.inflate（R.layout.grid_item_text，null）; 
 
 TextView personName =（TextView）view.findViewById（R.id.textItem）; 
 ImageView personThumb =（ImageView）view.findViewById（R.id.iconItem）; 
 
 //如果得到结果
 if（mList.size（）！= 0）{
 / *初始化图片* / 
 BitmapFactory.Options bmOptions; 
 bmOptions = new BitmapFactory.Options（）; 
 bmOptions.inSampleSize = 1; 
 
 / * 
位图bmpThumb = loadBitmap（mList.get（position）.accId，bmOptions，IMAGE_THUMB）; 
 
 if（bmpThumb！= null）{
 ImageHelper ih = new ImageHelper（）; 
 bmpThumb = ih.getRoundedCornerBitmap（bmpThumb，10）; 
 personThumb.setImageBitmap（bmpThumb）; 
} else {
 personThumb.setImageResource（mThumbs）; 
} 
 * / 
 
 personThumb.setImageResource（mThumbs）; 
 personName.setText（mList.get（position）.fullName.toString（））; 
} else {
 personThumb.setImageResource（mThumbs）; 
 personName.setText（添加好友）; 
} 
 
 
 
} else {
 view =（View）convertView; 
} 
返回视图; 
} 
  

摘自我的MainActivity

  protected void onCreate（Bundle savedInstanceState）{
 private GridView gridView; 
 gridView =（GridView）findViewById（R.id.thumb_grid_view）; 
 getFriends（）; 
} 
 
 private void getFriends（）{
 RetrieveFriendList task = new RetrieveFriendList（）; 
 task.execute（）; 
} 
 
 private class RetrieveFriendList extends AsyncTask< String，Void，ArrayList< Person>> {
 
 @Override 
 protected ArrayList< Person> doInBackground（String ... params）{
 blah ... 
 
 return mFriendList; 
 
 $ b @Override 
 protected void onPostExecute（final ArrayList< Person> result）{
 if（result！= null）{
 gridView.setAdapter （new ContactGridAdapter（getApplicationContext（），result））; 
} 
} 
} 
  

然而这不起作用我打算。我应该从MainActivity或从Adapter中填充默认值吗？

解决方案

试试这样做：

  @Override 
 public View getView（int position，View convertView，ViewGroup parent）{
 // TODO自动生成的方法存根
 
 LayoutInflater inflater =（LayoutInflater）mContext 
 .getSystemService（Context.LAYOUT_INFLATER_SERVICE）; 
 
查看视图; 
 
 if（position == 0）
 //填充默认项目
 else 
 //从json填充
 if（convertView == null）{ 
 view = new View（mContext）; 
 view = inflater.inflate（R.layout.grid_item_text，null）; 
 
 TextView personName =（TextView）view.findViewById（R.id.textItem）; 
 ImageView personThumb =（ImageView）view.findViewById（R.id.iconItem）; 
 
 //如果得到结果
 if（mList.size（）！= 0）{
 / *初始化图片* / 
 BitmapFactory.Options bmOptions; 
 bmOptions = new BitmapFactory.Options（）; 
 bmOptions.inSampleSize = 1; 
 
 / * 
位图bmpThumb = loadBitmap（mList.get（position）.accId，bmOptions，IMAGE_THUMB）; 
 
 if（bmpThumb！= null）{
 ImageHelper ih = new ImageHelper（）; 
 bmpThumb = ih.getRoundedCornerBitmap（bmpThumb，10）; 
 personThumb.setImageBitmap（bmpThumb）; 
} else {
 personThumb.setImageResource（mThumbs）; 
} 
 * / 
 
 personThumb.setImageResource（mThumbs）; 
 personName.setText（mList.get（position）.fullName.toString（））; 
} else {
 personThumb.setImageResource（mThumbs）; 
 personName.setText（添加好友）; 
} 
 
 
 
} else {
 view =（View）convertView; 
} 
返回视图; 
  

}

Hi i would like to set the first item of my GridView with a default value, and populate the rest of the item accordingly (based on JSON result)

My code consist of 2 classes 1. MainActivity 2. GridView Adapter

Here is the code for my GridAdapter

public class ContactGridAdapter extends ArrayAdapter<Person> {
*** SOME INITIALIZATION ***

public ContactGridAdapter(Context context, ArrayList<Person> values){
    super(context, R.layout.grid_item_text);
    mContext = context;
    mList = values;
}

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

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

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

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub

    LayoutInflater inflater = (LayoutInflater) mContext
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View view;

    if(convertView == null){
        view = new View(mContext);
        view = inflater.inflate(R.layout.grid_item_text, null);

        TextView personName = (TextView) view.findViewById(R.id.textItem);
        ImageView personThumb = (ImageView) view.findViewById(R.id.iconItem);

        // IF HAVE RESULT
        if(mList.size() != 0){
            /* INITIALIZES PHOTO */
            BitmapFactory.Options bmOptions;
            bmOptions = new BitmapFactory.Options();
            bmOptions.inSampleSize = 1;

            /*
            Bitmap bmpThumb = loadBitmap(mList.get(position).accId, bmOptions, IMAGE_THUMB);

            if(bmpThumb != null){
                ImageHelper ih = new ImageHelper();
                bmpThumb = ih.getRoundedCornerBitmap(bmpThumb, 10);
                personThumb.setImageBitmap(bmpThumb);
            }else{
                personThumb.setImageResource(mThumbs);
            }
            */

            personThumb.setImageResource(mThumbs);
            personName.setText(mList.get(position).fullName.toString());
        }else{
            personThumb.setImageResource(mThumbs);
            personName.setText("Add Friends");
        }



    }else{
        view = (View) convertView;
    }
    return view;
}

Excerpt from my MainActivity

protected void onCreate(Bundle savedInstanceState) {
private GridView gridView;
gridView = (GridView) findViewById(R.id.thumb_grid_view);
getFriends();
}

private void getFriends(){
    RetrieveFriendList task = new RetrieveFriendList();
    task.execute();
}

private class RetrieveFriendList extends AsyncTask<String, Void, ArrayList<Person>> {

        @Override
        protected ArrayList<Person> doInBackground(String... params) {
blah...

            return mFriendList;
        }

        @Override
        protected void onPostExecute(final ArrayList<Person> result) {          
            if(result != null){
                gridView.setAdapter(new ContactGridAdapter(getApplicationContext(), result));
            }
        }
    }

This however does not work as i intended. Should i populate the default value from MainActivity or from within the Adapter?

解决方案

Try doing this:

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    // TODO Auto-generated method stub

LayoutInflater inflater = (LayoutInflater) mContext
        .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

View view;

if(position == 0)
// Populate default item
else
// Populate from json
if(convertView == null){
    view = new View(mContext);
    view = inflater.inflate(R.layout.grid_item_text, null);

    TextView personName = (TextView) view.findViewById(R.id.textItem);
    ImageView personThumb = (ImageView) view.findViewById(R.id.iconItem);

    // IF HAVE RESULT
    if(mList.size() != 0){
        /* INITIALIZES PHOTO */
        BitmapFactory.Options bmOptions;
        bmOptions = new BitmapFactory.Options();
        bmOptions.inSampleSize = 1;

        /*
        Bitmap bmpThumb = loadBitmap(mList.get(position).accId, bmOptions, IMAGE_THUMB);

        if(bmpThumb != null){
            ImageHelper ih = new ImageHelper();
            bmpThumb = ih.getRoundedCornerBitmap(bmpThumb, 10);
            personThumb.setImageBitmap(bmpThumb);
        }else{
            personThumb.setImageResource(mThumbs);
        }
        */

        personThumb.setImageResource(mThumbs);
        personName.setText(mList.get(position).fullName.toString());
    }else{
        personThumb.setImageResource(mThumbs);
        personName.setText("Add Friends");
    }



}else{
    view = (View) convertView;
}
return view;

}

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