I am quite new to android development and I am facing a NullPointerException
when I am trying to call an AsyncTask
which is an inner class in another class.
I believe it is the way I am instantiating it but this is what I have:
// This onClick is in my adapter class - which is a separate Java File and class
@Override
public void onClick(View v) {
UploadRes uploadRes = new UploadRes();
UploadRes.UploadResConfirm uploadResConfirm = uploadRes.new UploadResConfirm(v.getContext());
uploadResConfirm.execute(fileName, filePath);
}
public class UploadResConfirm extends AsyncTask<String, String, String> {
Dialog dialog;
Context context;
public UploadResConfirm(Context context){
this.context = context;
}
@Override
protected void onPreExecute(){
dialog = new Dialog(UploadRes.this);
dialog.setTitle("Currently uploading");
dialog.show();
}
I believe it has got something to do with the dialog
box itself being instantiated in the AsyncTask
class.
The error stack trace
on Logcat
- its the Dialog
, I think its in the wrong place...
java.lang.NullPointerException
at codeman.androapp.UploadRes$UploadResConfirm.onPreExecute(UploadRes.java:246)
at android.os.AsyncTask.executeOnExecutor(AsyncTask.java:586)
at android.os.AsyncTask.execute(AsyncTask.java:534)
at android.view.View.performClick(View.java:4240)
at android.view.View$PerformClick.run(View.java:17721)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5103)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:737)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Some help if any would be much obliged.
Instead of dialog = new Dialog(UploadRes.this);
Try
dialog = new Dialog(context);
your are passing a wrong context to create dialog.
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