Question

Here are some facts about my app followed by a question

My app has two fragments.

My app creates certain file structure and documents on its first launch and it takes time, thus I am using AsyncTask class method to display ProgressDialog while the file structure is created. This is done in onCreate method of my MainActivity just like this:

public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        progress = new ProgressDialog(this);
        progress.setMessage("Loading...");

        File testFile = new File("/mnt/sdcard/myNewFolder");
        if (!testFile.exists()) {
            new MyTask(progress).execute();
            setContentView(R.layout.activity_main);
        } else
            setContentView(R.layout.activity_main);
    }

The problem is that onActivityCreated method of one of my Fragments starts running BEFORE new MyTask(progress).execute(); is finished. This causes errors and problems.

Why this onActivityCreated method of one of my Fragments runs BEFORE
new MyTask(progress).execute();???

Please do not assume that there are some silly mistakes that i didnt take into account xx

This is my MyTask class

public class MyTask extends AsyncTask<Void, Void, Void> {
    public MyTask(ProgressDialog progress) {
        // this.progress = progress;
    }

    public void onPreExecute() {
        progress.show();
    }

    public void onPostExecute(Void unused) {
        progress.dismiss();
    }

    @Override
    protected Void doInBackground(Void... params) {
        CreateFileStructure();
        return null;
    }
}

I need to create that file structure before anything else happens – that is why I am using this ProgressDialog. What am I doing wrong?

Answer 1

Here is the code that works for me – the ProgressDialog dialog is displayed while file structure and files are created, everything else (fragments, etc.) happens afterwards.

public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        progress = new ProgressDialog(this);
        progress.setMessage("Loading...");

        File testFile = new File("/mnt/sdcard/myNewFolder");
        if (!testFile.exists())
            new MyTask(progress).execute();
        else
            setContentView(R.layout.activity_main);
    }

    public class MyTask extends AsyncTask<Void, Void, Void> {
        public MyTask(ProgressDialog progress) {
            // this.progress = progress;
        }

        public void onPreExecute() {
            progress.show();
        }

        public void onPostExecute(Void unused) {

            progress.dismiss();
            setContentView(R.layout.activity_main);
        }

        @Override
        protected Void doInBackground(Void... params) {
            CreateFileStructure();
            return null;
        }
    }