Thread runs after statements below are executed

Question

I am showing a countdown while Realm dataBase is loaded from the asset file

 SharedPreferences wmbPreference = PreferenceManager.getDefaultSharedPreferences(this);
            boolean isFirstRun = wmbPreference.getBoolean("FIRSTRUN", true);
            if (isFirstRun)
            {
                handler = new Handler();
                Runnable r = new Runnable() {
                    public void run() {
                        Intent intent=new Intent(context,FirstRun.class);
                        startActivity(intent);
                    }
                };
                handler.post(r);


                RealmConfiguration config = new RealmConfiguration.Builder(context)
                        .name(Realm.DEFAULT_REALM_NAME)
                        .migration(new in.webic.longevity.longevity.Word())
                        .assetFile(context, "Default.realm")
                        .schemaVersion(0)
                        .build();

                realm = realm.getInstance(config);
                realm.close();

                SharedPreferences.Editor editor = wmbPreference.edit();
                editor.putBoolean("FIRSTRUN", false);
                editor.commit();

            }

Problem:

countdown should be show, rather a blank screen while asset file is copying as default database

Yet activity starts after few seconds(which is in the thread) taken by the code below to load the asset file,
Is there a better way to show countdown while Realm configuration is setup.
any help would be appreciated
Thanks

You tried to call this code in `android.intent.category.LAUNCHER` Activity? — Douglas Nassif Roma Junior, Oct 03 '16 at 11:36

Douglas Nassif Roma Junior · Accepted Answer · 2019-07-11T20:13:52.277

If you want to show a countdown, you must to copy the file manually.

How to copy file from assets to internal storage: Android - Copy assets to internal storage
How to update a progress or countdown: Updating the progress dialog on an uploading process
How to copy in correct Realm path: https://stackoverflow.com/a/36324183/2826279

And then, run the slow code in AsyncTask.

Like this:

public class LauncherActivity extends Activity {

     public void onCreate(...) {
        // init view

        new SlowTask().execute();
     }


     class SlowTask extends AsyncTask<Void, Void, Void>{

          protected Void doInBackground(Void... params) {

              // realm slow code here
              return null;
          }

          protected void onPostExecute(Void result) {
             // start your next activity here
          }
     }
}

sorry sir my whole application depends on database which needs to be loaded first hence, code needs to be run synchronously only — phpdroid, Oct 03 '16 at 11:55
Yes, my sample must be called in launcher activity, before everything else. — Douglas Nassif Roma Junior, Oct 03 '16 at 11:59

abdul khan · Answer 2 · 2016-10-04T07:34:18.907

0

You can't estimate the processing time. So countdown would not be a good option. Show some progress dialog before loading data from assets, then after data is loaded, dismiss the dialog.

Update: Actually what your problem is your thread executes before data is loaded! fine?. What you need to do is to do all processing task in AsyncTask class in which you should show progress dialog in onPreExecute(...) method. then do processing work in doInBackground(...) method. then in onPostExecute(...), dismiss progress dialog.

edited Oct 04 '16 at 07:34

answered Oct 03 '16 at 11:46

abdul khan

843
2
7
24

i agree, but my question run a thread before the below statement i.e default configuration is loaded – phpdroid Oct 03 '16 at 11:52

stknazev · Answer 3 · 2016-10-03T12:35:30.640

If you run some time-consuming task in main thread ("UI-thread", thread executed your Activity lifecycle methods) of your application, your app UI will be "freezed", which is generally undesirable. All background tasks (file\network io, heavy calculations) should be executed in separate thread.
If the background operation is started only for showing something in UI, consider using Loaders
If you need your object to be accessible from several Activites\Fragments, consider extending Application class and place link to your object there. If you need to "initialize" your object (load db in your case) at every app start, this can be done in onCreate() method of your Application class. If some objects (Activities) need to know, when the initialization is finished, you can use Observer pattern.
Sample code:
Your Application class:
```
public void onCreate() {   
    super.onCreate(); 
    mHandler = new Handler(); //for communicating with UI thread
    if (firstRun) { 
        new Thread(new Runnable() { 
            loadMyDb(); 
            mHandler.post(new Runnable()) { 
                notifyListeners(); 
            } 
        } 
    } 
}
```

Your Activity class:

protected void onCreate() {
    super.onCreate();
    setContentView(R.layout.your_layout); 
    //setup your layout and views
    MyApplication app = (MyApplication)getApplicationContext();
    if (app.isDbLoaded()) {
        showContent();
    } else {
        showProgressBar();
        app.addDbLoadListener(this);
    }
 }

 public void onDbLoaded() {
     hideProgressBar();
     app.removeDbLoadListener(this);
     showContent();
 }

whole application depends on database which needs to be loaded first hence, code needs to be run synchronously only. so i am starting a new activity to show something and first activity will load the heavy task — phpdroid, Oct 03 '16 at 11:58

Thread runs after statements below are executed

3 Answers3