java - 扩展 AsyncTask 的类中出现错误

Question

我一直在尝试从我的 dotnet webservice 获取一些数据并将结果以 json 格式传递到我的 android 应用程序。通过调用 invokeJSONWS 在 doInBackground 函数(正在被重写)中检索 json 数据。当我尝试调用 publishProgress 方法时，这给了我一个错误。我需要将 json 数据传递给这个 publishProgress 方法。我是否需要重写 publishProgress 因为它的返回类型是 string[]。

   private class ChartTask extends AsyncTask< String,Void, Void>{

    // Generates dummy data in a non-ui thread
    @Override
    protected Void doInBackground(String... params) {
        int i = 0;
        invokeJSONWS(params[0],"PopulateCities");
        return null;
        try{
            do{
                String [] values = new String[2];
                Random r = new Random();
                int visits = r.nextInt(27);

                values[0] = Integer.toString(i);
                values[1] = Integer.toString(visits);

                publishProgress(values);
                                 //Error here:The method publishProgress(Void...) in the type AsyncTask<String,Void,Void> is not applicable for the arguments (String[])                    
                Thread.sleep(1000);
                i++;
            }while(i<=30);
        }catch(Exception e){ }
        return null;
    }

    // Plotting generated data in the graph
    @Override
    protected void onProgressUpdate(String[] values) {
        visitsSeries.add(Integer.parseInt(values[0]), Integer.parseInt(values[1]));
        mChart.repaint();
    }
           //error here:The method onProgressUpdate(String[]) of type MainActivity.ChartTask must override or implement a supertype method

}


//Method which invoke web methods
public void invokeJSONWS(String country, String methName) {
    // Create request
    SoapObject request = new SoapObject(NAMESPACE, methName);
    // Property which holds input parameters
    PropertyInfo paramPI = new PropertyInfo();
    // Set Name
    paramPI.setName("country");
    // Set Value
    paramPI.setValue(country);
    // Set dataType
    paramPI.setType(String.class);
    // Add the property to request object
    request.addProperty(paramPI);
    // Create envelope
    SoapSerializationEnvelope envelope = new SoapSerializationEnvelope(
            SoapEnvelope.VER11);
    envelope.dotNet = true;
    // Set output SOAP object
    envelope.setOutputSoapObject(request);
    // Create HTTP call object
    HttpTransportSE androidHttpTransport = new HttpTransportSE(URL);

    try {
        // Invole web service
        androidHttpTransport.call(SOAP_ACTION+methName, envelope);
        // Get the response
        SoapPrimitive response = (SoapPrimitive) envelope.getResponse();
        // Assign it to static variable
        responseJSON = response.toString();

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


@Override
public boolean onCreateOptionsMenu(Menu menu) {
    getMenuInflater().inflate(R.menu.activity_main, menu);
    return true;
}

}

这个问题有办法解决吗？ 提前致谢!!

Logcat 看起来像这样

04-18 05:55:24.680: W/dalvikvm(1324): VFY: unable to resolve new-instance 430 (Lcom/google/gson/Gson;) in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;
04-18 05:55:24.680: D/dalvikvm(1324): VFY: replacing opcode 0x22 at 0x000f
04-18 05:55:24.820: E/dalvikvm(1324): Could not find class 'org.ksoap2.serialization.SoapObject', referenced from method in.wptrafficanalyzer.achartenginedynamicchart.MainActivity.invokeJSONWS
04-18 05:55:24.820: W/dalvikvm(1324): VFY: unable to resolve new-instance 584 (Lorg/ksoap2/serialization/SoapObject;) in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;
04-18 05:55:24.850: D/dalvikvm(1324): VFY: replacing opcode 0x22 at 0x0000
04-18 05:55:24.850: D/dalvikvm(1324): DexOpt: unable to opt direct call 0x0c0f at 0x11 in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;.<init>
04-18 05:55:24.860: D/dalvikvm(1324): DexOpt: unable to opt direct call 0x0fd1 at 0x04 in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;.invokeJSONWS
04-18 05:55:24.860: D/dalvikvm(1324): DexOpt: unable to opt direct call 0x0fcd at 0x09 in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;.invokeJSONWS
04-18 05:55:24.860: D/dalvikvm(1324): DexOpt: unable to opt direct call 0x0fd4 at 0x20 in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;.invokeJSONWS
04-18 05:55:24.860: D/dalvikvm(1324): DexOpt: unable to opt direct call 0x0fd7 at 0x2d in Lin/wptrafficanalyzer/achartenginedynamicchart/MainActivity;.invokeJSONWS
04-18 05:55:24.890: D/AndroidRuntime(1324): Shutting down VM
04-18 05:55:24.900: W/dalvikvm(1324): threadid=1: thread exiting with uncaught exception (group=0xb2ac5ba8)
04-18 05:55:24.920: E/AndroidRuntime(1324): FATAL EXCEPTION: main
04-18 05:55:24.920: E/AndroidRuntime(1324): Process: in.wptrafficanalyzer.achartenginedynamicchart, PID: 1324
04-18 05:55:24.920: E/AndroidRuntime(1324): java.lang.NoClassDefFoundError: com.google.gson.Gson
04-18 05:55:24.920: E/AndroidRuntime(1324):     at in.wptrafficanalyzer.achartenginedynamicchart.MainActivity.<init>(MainActivity.java:43)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at java.lang.Class.newInstanceImpl(Native Method)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at java.lang.Class.newInstance(Class.java:1208)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.Instrumentation.newActivity(Instrumentation.java:1061)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2112)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.ActivityThread.access$800(ActivityThread.java:135)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.os.Handler.dispatchMessage(Handler.java:102)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.os.Looper.loop(Looper.java:136)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at android.app.ActivityThread.main(ActivityThread.java:5017)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at java.lang.reflect.Method.invokeNative(Native Method)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at java.lang.reflect.Method.invoke(Method.java:515)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
04-18 05:55:24.920: E/AndroidRuntime(1324):     at dalvik.system.NativeStart.main(Native Method)
04-18 05:55:38.600: I/Process(1324): Sending signal. PID: 1324 SIG: 9

Answer 1

因为您已获取 Void 进度，所以它需要为 String，因为您期望 String 进度。