Question

I am trying to port an iPhone App to Android, but am having some startup difficulties.

I have the following function to get the data:

    public void onClick(View v) {
        try{
            //Toast.makeText(getApplicationContext(), "Starting update", Toast.LENGTH_SHORT).show();
            progressDialog = ProgressDialog.show(MainActivity.this, "", "Loading...");
            new Thread() {
                public void run() {
                    try{
                        DataManager manager = new DataManager(getApplicationContext());
                        manager.updateData();
                    } catch (Exception e) {
                        Log.e(TAG, e.getMessage());

                        AlertDialog alertDialog = new AlertDialog.Builder(MainActivity.this).create();
                        alertDialog.setTitle("Error...");
                        alertDialog.setMessage(e.getMessage());
                        alertDialog.show();
                    }
                    progressDialog.dismiss();
                }
            }.start();
        } catch (Exception e) {
            Log.e(TAG, "Problem with getting the data: " + e.getMessage());
            Toast.makeText(getApplicationContext(), "Error during update",
                    Toast.LENGTH_SHORT).show();
        }

    }

But if an exception occurs I get the following error (I initially tried to use an AsyncTask, but ran into the same problem):

08-29 20:23:24.389: ERROR/WindowManager(974): Activity org.idoms.iDomsAndroid.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@412fcc38 that was originally added here
        android.view.WindowLeaked: Activity org.idoms.iDomsAndroid.MainActivity has leaked window com.android.internal.policy.impl.PhoneWindow$DecorView@412fcc38 that was originally added here
        at android.view.ViewRootImpl.<init>(ViewRootImpl.java:344)
        at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:267)
        at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:215)
        at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:140)
        at android.view.Window$LocalWindowManager.addView(Window.java:537)
        at android.app.Dialog.show(Dialog.java:278)
        at android.app.ProgressDialog.show(ProgressDialog.java:116)
        at android.app.ProgressDialog.show(ProgressDialog.java:99)
        at android.app.ProgressDialog.show(ProgressDialog.java:94)
        at org.idoms.iDomsAndroid.MainActivity$1.onClick(MainActivity.java:46)
        at android.view.View.performClick(View.java:3511)
        at android.view.View$PerformClick.run(View.java:14105)
        at android.os.Handler.handleCallback(Handler.java:605)
        at android.os.Handler.dispatchMessage(Handler.java:92)
        at android.os.Looper.loop(Looper.java:137)
        at android.app.ActivityThread.main(ActivityThread.java:4424)
        at java.lang.reflect.Method.invokeNative(Native Method)
        at java.lang.reflect.Method.invoke(Method.java:511)
        at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
        at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
        at dalvik.system.NativeStart.main(Native Method)

What is the right way to do this?

Answer 1

My guess is, threads cannot interact with the main UI thread elements.

progressDialog was created in main Ui thread, other threads cannot interact with it. You can give it a signal in the fields and check its progress, but I would really recommend using Asynctask doing this task.

AsyncTask