Question

我收到了一些错误。我知道问题是什么，但我不知道如何解决它。

我有4个旋转器。每个微调器都有一个asynctask。简而言之，当我在spinner1上选择一个项目时，执行填充spinner2的第二个asynctask（选择的项目添加到第二个asynctask作为参数）继续这样。

但是在第一个asynctask结束之前，spinner2无法填充。在这种情况下，我收到错误。怎么解决？如何在第一个任务完成，第二个任务工作？

这是代码;

第一项任务

public class ilceDoldur extends AsyncTask<String[],String[],String[]>{

        @Override
        protected String[] doInBackground(String[]... params) {
            SoapObject request = new SoapObject(NAMESPACE, "ILCEGetir");
            SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
            envelope.dotNet = true;     
            envelope.setOutputSoapObject(request);
            HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
            androidHttpTransport.debug = true;

           try {

           androidHttpTransport.call("http://tempuri.org/ILCEGetir", envelope);
           SoapObject response = (SoapObject) envelope.getResponse();
           ilceList = new String[response.getPropertyCount()];

          for(int i=0;i<response.getPropertyCount();i++){          
                   ilceList[i] = response.getPropertyAsString(i).toString().trim();    
          }      
    } 
            catch (Exception e) {           
                e.printStackTrace();
           }    
            return ilceList;
        }

        protected void onPostExecute(String[] ilceList){
            ilceSpinner = (Spinner) findViewById(R.id.spinner1);
            ArrayAdapter<String> ilce_adapter = new ArrayAdapter<String>(NormalAnasayfa.this,android.R.layout.simple_spinner_item, ilceList);
            ilce_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            ilceSpinner.setAdapter(ilce_adapter);
            kontrol=true;
        }
    }

第二项任务

public class semtDoldur extends AsyncTask<String,String[],String[]>{

        @Override
        protected String[] doInBackground(String... ParamIlce) {
            PropertyInfo ilce = new PropertyInfo();
            ilce.name= "ilce";
            ilce.setValue(ParamIlce);
            ilce.type = PropertyInfo.STRING_CLASS;

            SoapObject request = new SoapObject(NAMESPACE, "SEMTGetir");
            request.addProperty(ilce);

            SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
            envelope.bodyOut=request;
            envelope.dotNet = true; 
            envelope.setOutputSoapObject(request);

            HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
            androidHttpTransport.debug = true;

           try {

           androidHttpTransport.call("http://tempuri.org/SEMTGetir", envelope);
           SoapObject response = (SoapObject) envelope.getResponse();
           semtList = new String[response.getPropertyCount()];

          for(int i=0;i<response.getPropertyCount();i++){          
                   semtList[i] = response.getPropertyAsString(i).toString().trim();    
          }      
    } 
            catch (Exception e) {           
                e.printStackTrace();
           }
            return semtList;
        }

        protected void onPostExecute(String[] semtList){
            semtSpinner = (Spinner) findViewById(R.id.spinner2);
            ArrayAdapter<String> semt_adapter = new ArrayAdapter<String>(NormalAnasayfa.this, android.R.layout.simple_spinner_item, semtList);
            semt_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            semtSpinner.setAdapter(semt_adapter);
            kontrol=true;
        }
    }

的onCreate（）

new ilceDoldur().execute();

        if(kontrol==true){
            kontrol=false;
            ilceSpinner.setOnItemSelectedListener(new OnItemSelectedListener() {

                public void onItemSelected(AdapterView<?> arg0, View arg1,
                        int arg2, long arg3) {
                    secilenIlce = ilceSpinner.getSelectedItem().toString().trim();
                    new semtDoldur().execute(secilenIlce);
                }
                public void onNothingSelected(AdapterView<?> arg0) {}
            });
        }

修改：我从我的Web服务获取数据并填充spinner1。我会得到数据（spinner1选择项目）？我在哪里填充spinner2执行第二个任务？

Answer 1

我找到了解决方案！

从网络服务获取数据：

private void ilceDoldur(){
        SoapObject request = new SoapObject(NAMESPACE, "ILCEGetir");
        SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(SoapEnvelope.VER11);
        envelope.dotNet = true;     
        envelope.setOutputSoapObject(request);
        HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);
        androidHttpTransport.debug = true;

       try {

       androidHttpTransport.call("http://tempuri.org/ILCEGetir", envelope);
       SoapObject response = (SoapObject) envelope.getResponse();
       ilceList = new String[response.getPropertyCount()];

      for(int i=0;i<response.getPropertyCount();i++){          
               ilceList[i] = response.getPropertyAsString(i).toString().trim();    
      }      
} 
        catch (Exception e) {           
            e.printStackTrace();
       }    
    }

我的AsyncTask：

public class ilceDoldur extends AsyncTask<String,String[],String[]>{

        @Override
        protected String[] doInBackground(String... params) {
            ilceDoldur();
            return ilceList;
        }

        protected void onPostExecute(String[] ilceList){
            ilceSpinner = (Spinner) findViewById(R.id.spinner1);
            ArrayAdapter<String> ilce_adapter = new ArrayAdapter<String>(NormalAnasayfa.this,android.R.layout.simple_spinner_item, ilceList);
            ilce_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
            ilceSpinner.setAdapter(ilce_adapter);
            ilceSecildi();
            }    
        }

获取spinner1选择的项目并启动第二个asynctask：

public String ilceSecildi(){
        ilceSpinner.setOnItemSelectedListener(new OnItemSelectedListener() {

            public void onItemSelected(AdapterView<?> arg0, View arg1,
                    int arg2, long arg3) {
                secilenIlce = ilceSpinner.getSelectedItem().toString().trim();
                new semtDoldurAsync(secilenIlce).execute();
            }
            public void onNothingSelected(AdapterView<?> arg0) {}
        });
        return secilenIlce;
    }

在onCreate中执行第一个任务：

new ilceDoldur().execute();

Answer 2

根据我对这个问题的理解，你说你有多个AsyncTasks来控制多个Spinners的内容。你做了一些交互，导致Spinner1被填充并立即进行另一个应该导致Spinner2被填充的交互，但观察到的行为是Spinner2在Spinner1完成填充之前不会填充。

这是因为AsyncTasks的默认行为是进程中的所有进程串行执行。如果希望AsyncTasks并行运行，请使用AsyncTask.executeOnExecutor（）并指定线程池执行程序。尽管如此，请仔细阅读AsyncTask的文档，默认的并行性行为随着时间的推移而发生了变化。

Answer 3

只需更改onPostExecute

即可

    protected void onPostExecute(String[] ilceList){
        ilceSpinner = (Spinner) findViewById(R.id.spinner1);
        ArrayAdapter<String> ilce_adapter = new ArrayAdapter<String>(NormalAnasayfa.this,android.R.layout.simple_spinner_item, ilceList);
        ilce_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        ilceSpinner.setAdapter(ilce_adapter);
        ilceSecildi();
        }    
    }

到

    protected void onPostExecute(String[] ilceList){
        ilceSpinner = (Spinner) findViewById(R.id.spinner1);
        ArrayAdapter<String> ilce_adapter = new ArrayAdapter<String>(getApplicationContext(),android.R.layout.simple_spinner_item, ilceList);
        ilce_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        ilceSpinner.setAdapter(ilce_adapter);
        ilceSecildi();
        }    
    }

Android Spinner上出现多个AsyncTasks问题

3 个答案: