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Progress Bar on Android gets displayed after complete onClick() execution

I have a Button, and upon pressing it, the onClick() would process user's request. However, this takes a little time, so I would like to have a View showing "Please wait, processing..." immediately upon pressing this Button, while its OnClickListener does its thing.
My problem is, this "Please wait, processing..." which I placed at the very beginning of onClick(), only appears AFTER the whole onClick() is done. In other words, after the whole processing is done. So, I was wondering, how do I make a View saying "Please wait, processing..." before the actual processing has begun?

As #Blundell pointed you may process long-running operation on a separate thread to avoid freezing of UI thread. However in Android there's a better alternative for general-purpose Handler which is called AsyncTask. Please refer to this tutorial for details.

You can do this by just using AsyncTask without dealing anything else.
First create new AsyncTask class on "onPreExecute" change ui to show
that you are processing sth
Second do your all backend time consuming job on "doInBackground"
method (do not call any ui updating method from here)
Third change your ui to show that process is finished or whatever you
wanna do.
yourUiButton.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View arg0) {
new NewTask().execute();
}
});
class NewTask extends AsyncTask<String, Void, Task>{
#Override
protected void onPreExecute() {
super.onPreExecute();
//this part runs on ui thread
//show your "wait while processing" view
}
#Override
protected Task doInBackground(String... arg0) {
//do your processing job here
//this part is not running on ui thread
return task;
}
#Override
protected void onPostExecute(Task result) {
super.onPostExecute(result);
//this part runs on ui thread
//run after your long process finished
//do whatever you want here like updating ui components
}}

Do the processing on another thread so that the UI can show your dialog.
// Show dialog
// Start a new thread , either like this or with an ASyncTask
new Thread(){
public void run(){
// Do your thang
// inform the UI thread you've finished
handler.sendEmptyMessage();
}
}
When the processing is done you will need to callback to the UI thread to dismiss oyur dialog.
Handler handler = new Handler(){
public void handleMessage(int what){
// dismiss your dialog
}
};

AsyncTasks.
Place the displaying of the progress dialog in onPreExecute
Do your thing in doInBackground
Update whatever needs to be updated in the UI, and close the dialog in onPostExecute

You will need something like this
public void onClick(View v){
//show message "Please wait, processing..."
Thread temp = new Thread(){
#Override
public void run(){
//Do everything you need
}
};
temp.start();
}
or if you want it to run in the UIThread (since it is an intensive task, I don't recommend this)
public void onClick(View v){
//show message "Please wait, processing..."
Runnable action = new Runnable(){
#Override
public void run(){
//Do everything you need
}
};
v.post(action);
}

put ur code inside a thread and use a progress dialogue there...
void fn_longprocess() {
m_ProgressDialog = ProgressDialog.show(this, " Please wait", "..", true);
fn_thread = new Runnable() {
#Override
public void run() {
try {
// do your long process here
runOnUiThread(UI_Thread);//call your ui thread here
}catch (Exception e) {
e.printStackTrace();
}
}
};
Thread thread = new Thread(null, thread1
"thread1");
thread.start();
}
then close your dialogue in the UI thread...hope it helps..

progress dialog in main activity's onCreate not shown

After the splash screen, it takes about 6 sec to load onCreate contents in the Main activity. So I want to show a progress dialog while loading and here's what I did:
import ...
private ProgressDialog mainProgress;
public void onCreate(Bundle davedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mProgress = new ProgressDialog (Main.this);
mProgress.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL);
mProgress.setMessage("Loading... please wait");
mProgress.setIndeterminate(false);
mProgress.setMax(100);
mProgress.setProgress(0);
mProgress.show();
---some code---
mProgress.setProgress(50);
---some code---
mProgress.setProgress(100);
mProgress.dismiss();
}
and it doesn't work... the screen stays black for 5-6 sec and then load the main layout. I dont know which part I did wrong :*(

You need to do start your busy code in an other thread (than the UI thread).
In your activity create the ProgressDialog and close it in the thread
mProgress = new ProgressDialog (Main.this);
Runnable runnable = new Runnable() {
#Override
public void run() {
// code that needs 6 seconds for execution
// after finishing, close the progress bar
mProgress.dismiss();
}
};
new Thread(runnable).start();

It's because you're doing everything on the UI thread, thus blocking it.
You should do all your heavy-lifting in a separate thread and update the progress dialog through that

Using progressDialog in android?

I am using this code to display a Progress Dialog which is working fine:
dialog = ProgressDialog.show(this, "Please wait",
"Gathering Information...", true);
Thread thread = new Thread()
{
#Override
public void run() {
if(Chapter_sync.size()>0){
storemodule();
c.open();
for(int i=0;i<Chapter_sync.size();i++)
{
downloadPDF(Chapter_sync.get(i));
System.out.println("SYNCED"+i);
c.update(Chapter_sync.get(i));
}
}dialog.dismiss();
}
};thread.start();
LinearLayout parentlayout=(LinearLayout)findViewById(R.id.chapterholder);
parentlayout.removeAllViews();
setUpViews();
}
}
Here what I am trying to do is display a Progress dialog till all computation is done.
As it completes i wanted to setup all views again. But the setUpViews() is called before the thread starts. I am not so good at thread basics .Could any one help me understand why is this happening and how can I get my own results?

The problem is you are not using handlers. Simply do this,
dialog = ProgressDialog.show(this, "Please wait",
"Gathering Information...", true);
Thread thread = new Thread()
{
#Override
public void run() {
if(Chapter_sync.size()>0){
storemodule();
c.open();
for(int i=0;i<Chapter_sync.size();i++)
{
downloadPDF(Chapter_sync.get(i));
System.out.println("SYNCED"+i);
c.update(Chapter_sync.get(i));
}
}dialog.dismiss();
}
handler.sendemptyMessage(0);
};thread.start();
And in your onCreate() create Handlers,
Handler handler=null;
handler=new Handler()
{
public void handleMessage(Message msg)
{
progressDialog.cancel();
if(msg.what==0)
{
LinearLayout parentlayout=(LinearLayout)findViewById(R.id.chapterholder);
parentlayout.removeAllViews();
setUpViews();
};
You can't update your UI from background thread. Either you have to use AsyncTask or to use handlers from your background thread to inform your main thread that the background action has been completed.

Thread scheduling is dependent on the operating system. So instantiating your thread does not ensure that your thread will run whenever you want.
The problem you are facing can be best handled using async task. Or if you have a callback that lets you know when your download is completed then you can dismiss the dialog on the callback. Make sure you dismiss it inside a UI thread by doing.
mActivity.runOnUiThread() or any other such methods.

In your code if u see
After Starting the Thread you have call your method setUpViews(), which does not wait for your thread to complete and setups your views.
Use Handler.post after the dialog is dismissed in your thread which gather your information.
handler.post(new Runnable()
{
setUpViews();
});
So after the your operations completed your setupViews will be called by your Handler.

progress dialog not showing in android?

when does the progress dialog not show in android? i want to know the circumstances when the above can happen:
in my case the progress dialog was not showing in this case:
func{
progressdialog.show();
....
.....
anotherfunction();
listview.setAdapter();
progressdialog.dismiss();
}
what is the general rule of thumb with dialog boxes?
thank you in advance.
EDIT
when the .show() command is executed the progress dialog should show. But when the otherfucntion() is called, does the previous command of progressdialog show stop?

Seems like you need to use AsyncTask the UI (including the progressDialog) will not update if the UI thread is still busy. There are many examples in SO for that.
And as a rule of thumb - if you need Progress dialog - you need AsyncTask.
It is not that any command stops, it is just that if you execute a sequence of methods on the UI thread, the UI will probably not be updated until the sequence is over, which is after progressDialog.dismiss(), so the progressDialog should not be displayed anymore.

I think You have to do this in your activity.
ProgressDialog _progressDialog = ProgressDialog.show(this,"Saving Data","Please wait......");
settintAdater();
private void settingAdater(){
Thread _thread = new Thread(){
public void run() {
Message _msg = new Message();
_msg.what = 1;
// Do your task where you want to rerieve data to set in adapet
YourCalss.this._handle.sendMessage(_msg);
};
};
_thread.start();
}
Handler _handle = new Handler(){
public void handleMessage(Message msg) {
switch(msg.what){
case 1:
_progressDialog.dismiss();
listview.setAdapter();
}
}
}

To show a ProgressDialog use
ProgressDialog progressDialog = ProgressDialog.show(PrintMain.this, "",
"Uploading Document. Please wait...", true);
And when you have completed your task use
progressDialog.dismiss();
to dismiss the ProgressDialog ..
You can call to show the ProgressDialog in your onPreExecute method of AsyncTask class and when your done dismiss it in the onPostExecute method

Android: ProgressDialog doesn't show

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.