Android: ProgressDialog doesn't show - android

I'm trying to create a ProgressDialog for an Android-App (just a simple one showing the user that stuff is happening, no buttons or anything) but I can't get it right. I've been through forums and tutorials as well as the Sample-Code that comes with the SDK, but to no avail.
This is what I got:
btnSubmit.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
(...)
ProgressDialog pd = new ProgressDialog(MyApp.this);
pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
pd.setMessage("Working...");
pd.setIndeterminate(true);
pd.setCancelable(false);
// now fetch the results
(...long time calculations here...)
// remove progress dialog
pd.dismiss();
I've also tried adding pd.show(); and messed around with the parameter in new ProgressDialog resulting in nothing at all (except errors that the chosen parameter won't work), meaning: the ProgressDialog won't ever show up. The app just keeps running as if I never added the dialog.
I don't know if I'm creating the dialog at the right place, I moved it around a bit but that, too, didnt't help. Maybe I'm in the wrong context? The above code is inside private ViewGroup _createInputForm() in MyApp.
Any hint is appreciated,

you have to call pd.show before the long calculation starts and then the calculation has to run in a separate thread. A soon as this thread is finished, you have to call pd.dismiss() to close the prgoress dialog.
here you can see an example:
the progressdialog is created and displayed and a thread is called to run a heavy calculation:
#Override
public void onClick(View v) {
pd = ProgressDialog.show(lexs, "Search", "Searching...", true, false);
Search search = new Search( ... );
SearchThread searchThread = new SearchThread(search);
searchThread.start();
}
and here the thread:
private class SearchThread extends Thread {
private Search search;
public SearchThread(Search search) {
this.search = search;
}
#Override
public void run() {
search.search();
handler.sendEmptyMessage(0);
}
private Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
displaySearchResults(search);
pd.dismiss();
}
};
}

I am giving you a solution for it,
try this...
First define the Progress Dialog in the Activity before onCreate() method
private ProgressDialog progressDialog;
Now in the onCreate method you might have the Any button click on which you will change the Activity on any action. Just set the Progress Bar there.
progressDialog = ProgressDialog.show(FoodDriveModule.this, "", "Loading...");
Now use thread to handle the Progress Bar to Display and hide
new Thread()
{
public void run()
{
try
{
sleep(1500);
// do the background process or any work that takes time to see progress dialog
}
catch (Exception e)
{
Log.e("tag",e.getMessage());
}
// dismiss the progress dialog
progressDialog.dismiss();
}
}.start();
That is all!

Progress Dialog doesn't show because you have to use a separated thread. The best practices in Android is to use AsyncTask ( highly recommended ).
See also this answer.

This is also possible by using AsyncTask. This class creates a thread for you. You should subclass it and fill in the doInBackground(...) method.

Related

How to display a loading screen while doing heavy computing in Android?

I am working on a program that searches the users phone for some date, which takes about 2-3 seconds. While it's computing I want to display a loading screen, so the user knows something indeed is happening. However, when I try to display a loading screen before the computations, nothing is displayed on the screen.
This is what I have:
ProgressDialog loading= new ProgressDialog(this);
loading.setTitle("Loading");
loading.setMessage("Please wait...");
loading.show();
//search stuff
loading.dismiss();
In addition to this, I have tried putting the ProgressDialog in a thread like the following,
new Thread(new Runnable(){
public void run(){
ProgressDialog loading= new ProgressDialog(this);//error here for "this"
loading.setTitle("Loading");
loading.setMessage("Please wait...");
loading.show();
}
});
//search stuff
but it fails due to the "this" keyword, I believe because its referring to an Activity and not a regular class, but I could be wrong...
How can I get the ProgressDialog to display properly?
Try to handle it in this way
mProgressDialog = ProgressDialog.show(this, "Please wait","Long operation starts...", true);
new Thread() {
#Override
public void run() {
//Do long operation stuff here search stuff
try {
// code runs in a thread
runOnUiThread(new Runnable() {
#Override
public void run() {
mProgressDialog.dismiss();
}
});
} catch (final Exception ex) {
}
}
}.start();
Use async task for heavy task. Put your progress dialog code in onPreExecute method progress dialog dismiss code in onPostExecute method and all your heavy task in doInBackground method.
try passing down the context on a new class with your progress bar (this goes on your main activity)
NAME_OF_YOUR_CLASS context = new NAME_OF_YOUR_CLASS(getApplicationContext());
and on your class call the method like this..(this goes on class)
public Networking(Context c) {
this.context= c;
}
dont forget to make context a field (private final Context context;)
hope this helps
also idk if this will work but try to extend AsyncTask and use methods to run your progress bar there.

Visibility of ProgressBar

I need to process some data when the user click the button in one activity, so the screen looks like the app stops for 2-3 seconds. It isn't a lot but I want to give the user information that everything is ok and IMO the best way will be the progressbar which is visible only when data are processed.
I found the code of ProgressBar and it looks like this:
<ProgressBar
android:id="#+id/loadingdata_progress"
style="?android:attr/progressBarStyle"
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_alignBottom="#+id/fin2_note"
android:layout_centerHorizontal="true"
android:indeterminate="true"
android:visibility="invisible" />
and inserted it on the middle of my layout.
And to try if the progressbar works, I put this code
loadingimage= (ProgressBar) findViewById(R.id.loadingdata_progress);
loadingimage.setVisibility(View.VISIBLE);
into onCreate method and everything looks fine.
Then I recreated the code to show this progressbar only if the data is processed.
After click the user invoke this method
public void fin2_clickOnFinalization(View v)
{
loadingimage= (ProgressBar) findViewById(R.id.loadingdata_progress);
loadingimage.setVisibility(View.VISIBLE);
// code where data is processing
loadingimage.setVisibility(View.INVISIBLE);
}
and nothing appear on the screen. I don't know where is the mistake. If I found the progress bar by id, It's strange for me that I can control it in onCreate method but in onclick method it's out of my control.
Your UI thread cannot show progress bar cause it is busy due to your data processing. Try to use this kind of code :
public void fin2_clickOnFinalization(View v) {
new YourAsyncTask().execute();
}
private class YourAsyncTask extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... args) {
// code where data is processing
return null;
}
#Override
protected void onPostExecute(Void result) {
loadingimage.setVisibility(View.INVISIBLE);
super.onPostExecute(result);
}
#Override
protected void onPreExecute() {
super.onPreExecute();
loadingimage.setVisibility(View.VISIBLE);
}
}
EDIT:
AsyncTask let you run code in separate thread and make app more responsive, just put time-consuming code inside doInBackground.
You're not giving the UI time to refresh. Your "data processing" code is running on the UI thread, blocking any visible changes. By the time the system gets control to refresh the display, you've already set it back to invisible.
To fix this, move your processing code to a separate thread or AsyncTask. Then you can set the progress bar to visible, start the task, and have it turn itself invisible once it's done.
I'd recommend AsyncTask for this purpose about 90% of the time on Android, since it comes stock with useful callbacks. The developer guide for it(in the Javadoc linked above) is pretty explicit, and outlines all the steps you need to take.
AsyncTask is too heavily-weighted for such task.
A better much solution
Handler handler = new Handler(getMainLooper());
handler.post(new Runnable() {
#Override
public void run() {
loadingimage.setVisibility(View.VISIBLE);
}
});
Or even simpler (does essentially the same thing as solution above)
runOnUiThread(new Runnable() {
#Override
public void run() {
loadingimage.setVisibility(View.VISIBLE);
}
});
You can try to create a global ProgressDialog not in the layout but in your activity like:
public class MyActivity {
ProgressDialog progress = null;
protected void onCreate(...) {
progressDialog = new ProgressDialog(this);
progressDialog.setCancelable(false);
progressDialog.setTitle("Progress");
}
public void fin2_clickOnFinalization(View v)
{
progress.show();
// code where data is processing
progress.dismiss();
}
}
Hope i it helps

ProgressDialog communicate with AsyncTask in android

Tips or ideas on how ProgressDialog can communicate with asyncTask.
For example when I click the button, the program will validate the input to internet, This is should not be interupted. so I use ProgressDialog.
After progressDialog.dismiss(), I need to refresh the view by calling the asyncTask.
I have tried some ways but it's failed, for example
* I execute asynTask after progressdialog.dismiss().
* put execution asynctask inside dialogbox after progressdialog thread.
in other word, is there any way to tell asynctask that progressdialog has been dismissed. Or is there communication such as message between threads ?
here is the example of my code:
btnPost.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
stockProgressDialog = ProgressDialog.show(PostActivity.this,
"Please wait...", "Check the post");
new Thread() {
public void run() {
try{
/* Connect to Internet API */
stockProgressDialog.dismiss();
} catch (Exception e) { }
// Dismiss the Dialog
}
}.start();
new LookUpTask().execute();
}
});
Yes, there is a way to tell asyncTask that progressDialog has been dismissed. you can use one onDismissListener
#Override
public Dialog onCreateDialog(int id){
if(id==DIALOG_PROGRESS_DIALOG){
stockProgressDialog = new ProgressDialog(Main.this);
stockProgressDialog.setTitle("Please wait...");
stockProgressDialog.setMessage("Check the post");
stockProgressDialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
#Override
public void onDismiss(DialogInterface dialog) {
textView.setText("Waiting the 5 secs...");
myAsyncTask.execute("start it");
//Or myAsyncTask.cancel(true); if you want to interrupt your asyncTask
}
});
return stockProgressDialog;
} else return super.onCreateDialog(id);
}
You can cancel an AsyncTask by calling AsyncTask.cancel(..) and then start up a new AsyncTask. You are not supposed to run the AsyncTask as a parallel activity - it is supposed to be able to run and finish without outside intervention.
Extend async and look into returning a result from doInBackground. onProgress update can dismiss your Progress dialog under control of the async task. Handle the result from doInBackground in onPostExecute.
//create the task
theBackground = new Background();
theBackground.execute("");
--------
private class Background extends AsyncTask<String, String, String>{
protected String doInBackground(String...str ) {
publishProgress("##0");
//do a bunch of stuff
publishProgress(#001);
return("true");
}
protected void onProgressUpdate(String... str ) {
//do stuff based on the progress string and eventually
myProgressDialog.dismiss();
}
protected void onPostExecute(String result) {
}
}
I'm not sure why you're using a thread in one case, but an AsyncTask in another when you could just use two AsyncTasks... Actually, unless I'm missing something, in your case the most straightforward way is to combine the two bits of work into one AsyncTask and simply create and destroy the dialog in the AsyncTask callbacks. In pseudo-code:
onPreExecute
show dialog
doInBackground
do internet stuff
onPostExecute
update views
close dialog
Is there a reason why you're trying to update the views in its own AsyncTask? If you're updating views, you probably need to do the work in the UI thread anyway...

Using ProgressDialog in android application startup

How can I show a progressDialog during the start up of an application. I have shown a progressDialog in the oncreate method and its not showing when launching the application.
I have gone through this:
ProgressDialog not showing until after function finishes
I have tried the solution explained for the above question. But its not working perfectly.
Here is my code:
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dash);
progressDialog = ProgressDialog.show(this, "", "Loading...");
//Run background UI thread
Thread laucherThread = new Thread(new Runnable() {
public void run() {
Looper.prepare(); //I had to include this to prevent force close error
startService(new Intent(DroidChirp.this,ChirpService.class));
doBindService();
Log.e(MY_DEBUG_TAG, "Prepairing to close the dialog");
runOnUiThread(new Runnable() {
public void run() {
progressDialog.dismiss();
}
});
Log.e(MY_DEBUG_TAG, "Closed the dialog");
}
});
laucherThread.start();
}
What I need to do is:
Show a progressDialog until all the initial setup is finished
Issues I am facing :
ProgressDialog is not showing at the start up.
There is a delay when starting the application(Showing blank for sometime).
ProgressDialog appears just before finishing the initial setup.
Can anyone suggest me how can I establish this feature. Its a tablelayout with list view for each tab.
If you want to show a progress dialog, while fetching data or something like this, you need to use AsyncTask with ProgressDialog bounded. See an example here.

Long delay between ProgressDialog.dismiss() and AlertDialog.show()

I'm using a standard ProgressDialog implementation: I set up a thread to run a long task, and when it's done it dismisses the ProgressDialog.
#Override
public void onCreate( Bundle bundle ) {
super.onCreate( bundle );
context = this;
progress = ProgressDialog.show( this, "Running", "Please wait..", true, false);
progress.setOnDismissListener( new OnDismissListener() {
public void onDismiss(DialogInterface dialog) {
showResults();
}
});
new DeleteThread().start();
}
And the Thread looks like this:
private class DeleteThread extends Thread {
public DeleteThread() {}
#Override
public void run() {
// long process during which we populate
// a LinearLayout with many other Views
progress.dismiss();
}
}
And in showResults() we take the LinearLayout now filled with Views and set it as the content of an AlertDialog.
The problem is, the ProgressDialog goes away and there's still a long period of time (10-12sec) where nothing is happening before the AlertDialog pops up. Is there a way to make this transition instantaneously?
I know this answer might be coming in a bit late, but what the heck.
I see that you're triggering the showResults() method from the onDismiss callback. I would suggest you do it the other way around. To do that you may need to use the AsyncTask class.
The AsyncTask allows you to easily setup tasks to run in a spawned thread, to update a progress bar if needed (not required, but might be a nice touch in your case) and of course to run some code on the UI thread once the spawned thread completes. For your case, I would place your populating of layoutview in the AsyncTask.doInBackground() method. Then, you'd want to add the showResults() method call in AsyncTask.onPostExecute(). At the bottom of onPostExecute() you should then dismiss your progress dialog. That SHOULD give you the results you want.
As a bonus, you might want to create a constructor for your AsyncTask class and place the creation of the ProgressDialog in there. That way the ProgressDialog will be completely encapsulated within that class and everything is nice and clean. So, something like this:
class MyAsyncClass extends AsyncClass
{
ProgressDialog m_progress;
public MyAsyncClass()
{
m_progress = ProgressDialog.show( this, "Running", "Please wait..", true, false);
}
protected Long doInBackground(Object... data) {
// Do your long process of populating a LinearLayout with many other Views
}
protected void onPostExecute(Long result) {
showResults();
m_progress.dismiss();
}
}
NOTE: Above needs some extra parameters to the class, but you get the idea.
I'm going to venture a guess as a novice Android developer and suggest that while the pointers are generated for the LinearLayout, the layout itself hasn't been populated with content and therefor is populating when you call progress.dismiss()
You will probably have to render the view prior to setting to the AlertDialogs content. http://developer.android.com/guide/topics/ui/how-android-draws.html might have some help in that respect, unfortunately my laptop is have HDD issues so I don't have the Android Development Environment installed and can't try it. But I'd try an invalidate on the LinearLayout right before progress.dismiss(), I hope that helps :S
Make use of something like this below and use an AsyncTask that dismisses the dialog once it is done:
final ProgressDialog progressDialog = new ProgressDialog(v.getContext());
progressDialog.setCancelable(false);
progressDialog.setMessage(v.getContext().getText(R.string.defaultQuantities));
progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
progressDialog.setMax(100);
new CountDownTimer(250, 250) {
public void onTick(long millisUntilFinished) {
}
public void onFinish() {
if (progressDialog.getProgress() < 100) {
progressDialog.show();
}
}
}.start();

Categories

Resources