java – AutoCompleteTextView和Async类

2023年2月4日 141次阅读

我是
Android世界的新手,我建立了一个基于2.1 Google API的小型训练软件.

那时我还不知道主线程和工作线程,所以我将所有代码都放在主线程中.

从那时起,我使用异步类修复了我的netwkork访问,以适应4.0 Google API.

好的,但最后一件事困扰着我,我找不到任何线索.

它是关于字段ville上的AutoCompleteTextView(法语中的“town”).

之前(2.1)：

public void onTextChanged(CharSequence s, int start, int before, int count) 
{
String result = null;
InputStream is = null;
List<String> r = new ArrayList<String>();

    if (ville.enoughToFilter())
    {
        is = connexionHttp(BASE_URL + "ville.php?ville=" + ville.getText());
        result = lectureData(is);

        try
        {           
            JSONArray jArray = new JSONArray(result);
            JSONObject json_data=null;
            for(int i=0;i<jArray.length();i++)
            {
                   json_data = jArray.getJSONObject(i);  
                   r.add(json_data.getString("VILLE"));
                   a_idVil.add(json_data.getString("CLEF_VILLE"));      
            }
            ville.setAdapter(new ArrayAdapter<String>(this,android.R.layout.simple_selectable_list_item,r));
            ville.setOnItemSelectedListener(new villeListener());

        }
        catch(JSONException e1)
        {
                Toast.makeText(getBaseContext(),e1.toString() ,Toast.LENGTH_LONG).show();
                Log.d("***** TestActivity/onTextChanged: JSONException *****", "--"+e1.toString()+"--");
        } 
        catch(ParseException e1) 
        {
                Toast.makeText(getBaseContext(),e1.toString() ,Toast.LENGTH_LONG).show();
                Log.d("***** TestActivity/onTextChanged: ParseException *****", "--"+e1.toString()+"--");
        }
    }
}
public class villeListener implements OnItemSelectedListener 
{
    public void onItemSelected(AdapterView<?> parent, View v, int pos, long row) 
    {
        villePosition = pos;    
    }
    public void onNothingSelected(AdapterView<?> arg0)  {   }
}

 

100％完美运行：

– >在第4个字符之后,查询在MySql上运行以查找以4个给定字母开头的所有城镇,并显示选择列表以选择正确的字符：OK

– >听众给出选择城镇的索引：好的

之后(4.0)

public void onTextChanged(CharSequence s, int start, int before, int count) 
{           
if (ville.enoughToFilter())
{           
    new RemplirVille().execute(BASE_URL + "ville.php?ville=" + ville.getText());
    Log.d("***********","AVANT");  
    ville.setOnItemSelectedListener(new villeListener());
    Log.d("***********","APRES");           
}

}
public class villeListener implements OnItemSelectedListener 
{
public void onItemSelected(AdapterView<?> parent, View v, int pos, long row) 
{
    villePosition = pos;
    Log.d("*************9999999", "1111111111");
}
public void onNothingSelected(AdapterView<?> arg0)  {   }
}

class RemplirVille extends AsyncTask<String, String, List<String>>
{
Integer errorMsgId;
String  errorMsgParam;

protected List<String> doInBackground(String... param)
{
    List<String> listeAffichageVille = new ArrayList<String>();
    ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();

    try 
    {
             HttpClient httpclient = new DefaultHttpClient();      
             HttpPost httppost = new HttpPost(param[0]);
             httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
             HttpResponse response = httpclient.execute(httppost);     
             if (response.getStatusLine().getStatusCode() < 400) 
             {
                  HttpEntity entity = response.getEntity();
                  String entityStr = EntityUtils.toString(entity);
                  JSONArray json_array = new JSONArray(entityStr);

                  for(int i=0;i<json_array.length();i++) 
                  {
                      JSONObject json_ligne = json_array.getJSONObject(i);                            
                      listeAffichageVille.add(json_ligne.getString("VILLE"));
                      a_idVil.add(json_ligne.getString("CLEF_VILLE"));
                  }
            } 
            else 
            {
                Log.d("***** TestActivity/ASYNC RemplirVille: EXCEPTION http error *****", "--"+response.getStatusLine().toString()+"--"); 
                this.errorMsgId = R.string.http_site_error;
                listeAffichageVille = null;
            }
    } 
    catch (Exception ex) 
    {
            Log.d("***** TestActivity/ASYNC RemplirVille: EXCEPTION decode error *****", "--"+ex.toString()+"--");
            this.errorMsgId = R.string.http_decode_error;
            this.errorMsgParam = ex.getLocalizedMessage();
            listeAffichageVille = null;
    }
    return listeAffichageVille;
}

protected void onProgressUpdate(String... item) {   }
protected void onPreExecute(List<String> list)  {   }
protected void onPostExecute(List<String> list)     
{               
    if (list == null)
    {
          if (this.errorMsgId != null) 
          {
              String msg = TestActivity.this.getString(this.errorMsgId);
              Toast.makeText(TestActivity.this,msg,Toast.LENGTH_LONG).show();
          }    
    }
    else            
    {
        ville.setAdapter(new ArrayAdapter<String>(TestActivity.this,android.R.layout.simple_selectable_list_item,list));
    }
}   
}

遇到麻烦：

– >你必须放入(足够的ToFilter 1)caractères来显示城镇列表：坏

– >听众甚至不再参与了：不好

事实上,足够ToFilter运行良好,它启动RemplirVille类,运行正常,但它不显示列表！

但是,如果再增加一个角色：
– > enoughToFilter仍然运作良好
– > RemplirVille再次提供数据….但这次选择列表显示良好.

关于那个话题的任何想法？
我想这是一个上下文问题,但即使使用GetApplicationCOntext,我也无法得到它.

谢谢.

最佳答案 调用AutoCompleteTextView.setAdapter()不会自动显示下拉列表,但您可以强制使用AutoCompleteTextView.showDropDown()显示下拉列表.

protected void onPostExecute(List<String> list){
    //...
    ville.setAdapter(new ArrayAdapter<String>(TestActivity.this,android.R.layout.simple_selectable_list_item,list));
    if(ville.isInputMethodTarget()){
        ville.showDropDown();
    }
    //...
}

如果没有这个,在输入下一个字符之前不会显示下拉列表,这会产生(足够的ToFilter 1)问题.

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