在ListView中自定义适配器使用包含HashMap [英] Using hashMaps in custom adapters for listView

问题描述

以下是我目前正在使用一个ListView的code：

The following is the code that I am currently using for a listView:

private class Asyncprojectlist extends AsyncTask<Void, Void, Void>{
        JSONArray JSar;
        JSONObject JSob;
        String project_title, project_sector;
        @Override
        protected void onPreExecute() {
            progressDialog =  new ProgressDialog(Allprojects.this);
            progressDialog.setCancelable(false);
            progressDialog.setMessage("Loading...");
            progressDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
            progressDialog.setProgress(0);
            progressDialog.show();
        }

        @Override
        protected Void doInBackground(Void... params) {
            UserFunctions user = new UserFunctions();
            JSob = user.allprojects();
            try {
                JSar = JSob.getJSONArray("data");

            } catch (JSONException e1) {
                e1.printStackTrace();
            }
            for(int i=0; i<JSar.length(); i++){
                try {
                    JSONObject newobj = JSar.getJSONObject(i);
                    project_title = newobj.getString("title");
                    project_sector = newobj.getString("sector");

                    HashMap<String, String> single = new HashMap<String, String>();
                    single.put("title", project_title);
                    single.put("sector", project_sector);

                    all_list.add(single);

                } catch (JSONException e) {
                    e.printStackTrace();
                }

            }
//          Log.i("json object", JSar.toString());
            return null;
        }

        @Override
        protected void onPostExecute(Void result) {
            ListAdapter adapter = new SimpleAdapter(getApplicationContext(), all_list, R.layout.projectlist_frame, 
                    new String[]{"title","sector"}, new int[]{R.id.projecttitle, R.id.projectsector});
            setListAdapter(adapter);
            progressDialog.dismiss();
            list = getListView();
            list.setOnItemClickListener(new AdapterView.OnItemClickListener() {

                @Override
                public void onItemClick(AdapterView<?> parent, View viewClicked,
                        int position, long id) {

                    Intent toindividual = new Intent(Allprojects.this, Individual_project.class);
                    try {
                        toindividual.putExtra("nid", JSar.getJSONObject(position).getString("id"));
                        startActivity(toindividual);

                    } catch (JSONException e) {
                        e.printStackTrace();
                    }
                }
            });

}

下面的API是被要求来获取数据和 all_list 是的ArrayList＆LT; HashMap的＆LT;＆GT;＆GT; 在那里使用的 SimpleAdapter 来赋值，如 projectTitle 和 projectStatus 在的ListView 布局。这里的一切完美的作品。但我有一个很难实施复选框监听器是在ListView的布局。我认为，需要一个定制的适配器。在我试图建立一个自定义适配器我不能拿出一个工作code。请实现自定义适配器，以便在ListView可以有帮助的复选框的 CheckChangeListener 实施

Here the an api is being called upon to fetch data and the all_list is an ArrayList<HashMap<>> where it is used by the SimpleAdapter to assign values such as projectTitle and projectStatus on the listView layout. Everything here works perfectly. But I am having a hard time implementing the checkBox listener which is in the listView's layout. I believe that a custom adapter is needed. In my attempt to build a custom adapter I could not come up with a working code. Please help in implementing a custom adapter so that the listView can have the checkBox's CheckChangeListener implemented.

推荐答案

你可以为它创建的是定制适配器。在这个适配器，你必须设置 CheckChangeListener 在复选框在 getView 方法。

you can create a custome adapter for it. In this adapter you have to set CheckChangeListener on checkbox in getView method.

public class MyBaseAdapter extends BaseAdapter {


 private Context mContext;
 private LayoutInflater mInflater;

 public MyBaseAdapter(Context context) {

  this.mContext = context;
  mInflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
 }

 public View getView(int position, View convertView, ViewGroup parent) {
  ViewHolder holder;

  if (convertView == null) {
   holder = new ViewHolder();

   convertView = mInflater.inflate(R.layout.row_layout, null);

  holder.txtName = (TextView) convertView.findViewById(R.id.textView1);
  holder.chkTick = (CheckBox) convertView.findViewById(R.id.checkBox1);

   convertView.setTag(holder);
  } else {
   holder = (ViewHolder) convertView.getTag();
  }

  final int pos = position;
  holder.txtName.setText("ABC");
  holder.chkTick.setOnCheckedChangeListener(new OnCheckedChangeListener() {
   public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked){
    Toast.makeText(mContext, "Checked", 
        Toast.LENGTH_SHORT).show(); 
}
   }
  });

  return convertView;
 }

您还可以检查此 LINK1 ，<一个href=\"http://androidcocktail.blogspot.in/2012/04/adding-checkboxes-to-custom-listview-in.html\">link2了解更多详情

You may also check this link1,link2 for more details

您可以用HashMap custome适配器和 UI设定值如下

You can use hashMap for custome adapter and set value in UI as follow

public class HashMapAdapter extends BaseAdapter {

private HashMap<String, String> mData = new HashMap<String, String>();
private String[] mKeys;
public HashMapAdapter(HashMap<String, String> data){
    mData  = data;
    mKeys = mData.keySet().toArray(new String[data.size()]);
}

@Override
public int getCount() {
    return mData.size();
}

@Override
public Object getItem(int position) {
    return mData.get(mKeys[position]);
}

@Override
public long getItemId(int arg0) {
    return arg0;
}

@Override
public View getView(int pos, View convertView, ViewGroup parent) {
    String key = mKeys[pos];
    String Value = getItem(pos).toString();

    //do your view stuff here

    return convertView;
}
}

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