Develop Reference

Displaying a ProgressDialog while waiting for a joined Thread

In my Activity, I load the content for a list from a DB, and want to display a ProgressDialog while it´s loading.
I got both working on it´s own, but if I load the data in a thread (which I should do?), the list is displayed before it´s data is loaded. But if I use join, the ProgressDialog doesnt even appear.
How can I combine this? Or is this not possible at all with threads? (AsyncTask maybe?)
Here´s the code for reference:
final ProgressDialog progressD=ProgressDialog.show(ShopSwitchActivity.this, "", "Loading..", true);
Thread myThread = new Thread(new Runnable() {
#Override
public void run() {
try
{
getData();
}catch(Exception e){}
}
});
myThread.start();
try {
myThread.join();
} catch (InterruptedException e) {
}
progressD.dismiss();
EDIT: Updated Code with AsyncTask:
public class LoadList extends AsyncTask<String, Void, Boolean> {
ProgressDialog dialog;
ShopSwitchActivity activity;
public LoadList(ShopSwitchActivity activity) {
this.activity = activity;
dialog = new ProgressDialog(activity);
}
protected void onPreExecute() {
this.dialog.setMessage("Loading...");
this.dialog.show();
}
#Override
protected void onPostExecute(final Boolean success) {
if (dialog.isShowing()) {
dialog.dismiss();
}
}
protected Boolean doInBackground(final String... args) {
try{
activity.getData();
} catch (Exception e) {
Log.e("error", e.getMessage());
}
return true;
}
}
Edit: My Solution
Using AsyncTask now to load the Data, and after it´s done, I refresh the list with the new data.

You can do it with AsyncTask. Write AsyncTask class in your main class that you want to do your operations. You can create the progress dialog in preexcecute of your async class and dismiss in onpostexecute of async class. Here is how you will do this:
class MyAsync extends AsyncTask<String, Void, Void> {
ProgressDialog pd;
Context co;
MyActivity ma;
public MyAsync (MyActivity ma){
this.ma= ma;
this.co = ma;
pd= new ProgressDialog(co);
}
#Override
protected void onPreExecute() {
this.pd.show();
super.onPreExecute();
}
#Override
protected Void doInBackground(String... params) {
// do your database operations here
return null;
}
#Override
protected void onPostExecute(Void result) {
// show db results and dismiss progress dialog pd.dismiss();
super.onPostExecute(result);
}
}
in MyActivity call as :
MyActivity ma = this;
new MyAsync(ma).execute();

You seem to miss the point of a thread. A thread occurs at the same time as your application. So your app doesn't call start then wait for the thread to be over- if it did you could just use a function. Instead your code continues to run. So if you just call join immediately, you're not doing anything. You'd get around a NetworkOnMainThreadException this way, but you'd still hold up the UI thread making your app totally non-responsive (and as a result not showing the dialog), and you'd eventually crash when a watchdog timer kills you.
Instead, the best way to handle this is to use an AsyncTask. Call getData in doInBackground(). Then dismiss the dialog in onPostExecute.

You should use AsyncTask instead actually.
Here is the link to the library. It is fairly simple:
1) onPreExecute() = show ProgressDialog
2) doInBackground() = execute your code
3) onPostExecute() = dismiss ProgressDialog
Here's a nice tutorial too.
In general:
#Override
protected void onPreExecute() {
dialog = new ProgressDialog(this.context);
dialog.setMessage("Loading...");
dialog.setCanceledOnTouchOutside(false);
}
#Override
protected void onPostExecute(String result) {
if(dialog.isShowing()) {
dialog.dismiss();
}
}

private Thread myThread;
private ProgressDialog mProgDialog;
mProgDialog = ProgressDialog.show(ShopSwitchActivity.this,"","Laden..", true);
myThread= new Thread(new Runnable()
{
public void run()
{
myThread.setPriority(Thread.MIN_PRIORITY);
try
{
getData();
}catch(Exception e){}
runOnUiThread(new Runnable()
{
public void run()
{
if (mProgDialog != null&& mProgDialog.isShowing())
mProgDialog.dismiss();
} }
});
}
});
myThread.start();

My ProgressDialog doesn't dismiss even after the view has been loaded.

I want to show a Progress-Dialog before my view has been loaded.
First i wrote the code in onCreate() but the dialog doesn't appear in that case. So i wrote it in onResume() but in this case, it doesn't disappear even after the view has been loaded. can anyone tell whats going wrong here?
protected void onResume() {
// TODO Auto-generated method stub
super.onResume();
dialog = ProgressDialog.show(this, "", "Please wait...", true);
//dialog.cancel();
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 progressdialog
dialog.dismiss();
}
}.start();
citySelected.setText(fetchCity);
spinner.setSelection(getBG);
}

You cant update UI(which is in main UIthread) from other threads. If you want to run any query in the background, you can use AsyncTask.
In onPreExecute method, show dialog and onPostExecute you can dismiss the dialog.
If you want to use Thread, then update UI using handlers.
Using AsyncTask
public class MyAsyncTask extends AsyncTask<String, Void, String> {
ProgressDialog dialog = new ProgressDialog(ActivityName.this);
#Override
protected void onPreExecute() {
dialog.show();
super.onPreExecute();
}
#Override
protected String doInBackground(String... params) {
try {
Thread.sleep(3000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String result) {
dialog.dismiss();
super.onPostExecute(result);
}
}
In Activity onCreate Method,
MyAsyncTask task = new MyAsyncTask();
task.execute();

better to use Asynctask ......... but if you still want same or want to know the solution only then can try
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());
}
YourActivity.this.runOnUIThread(new Runnable(){
#Override
public void run(){
// dismiss the progressdialog
dialog.dismiss();
});
}
}.start();

You can use AsyncTask. It is better than Thread
private class DownloadingProgressTask extends
AsyncTask<String, Void, Boolean> {
private ProgressDialog dialog = new ProgressDialog(ShowDescription.this);
protected void onPreExecute() {
this.dialog.setMessage("Please wait");
this.dialog.show();
}
protected Boolean doInBackground(final String... args) {
try {
downloadFile(b.getString("URL"));
return true;
} catch (Exception e) {
Log.e("tag", "error", e);
return false;
}
}
#Override
protected void onPostExecute(final Boolean success) {
if (dialog.isShowing()) {
dialog.dismiss();
}
}
}

progress Dialog simpel

i want to add a progress Dialog button when i click on this button before the new activity apperar, i think i don't need a thread, i did search but i find only that i need to do a thread and many other think it s not clear
i just want when i clik on a progress Dialog say to the user to wait so a few sec the other activity will appear that's all:
btn_newsfeed.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
// Launching News Feed Screen
Intent i = new Intent(getApplicationContext(), CustomizedListView.class);
startActivity(i);
}
});

There are three different different ways in which you can use a ProgressDailog -using threads, handlers and async tasks.
here a example of async task for using a progress Dialog
private class Operation extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... params)
{
// code to be executed in background thread
for(int i=0;i<5;i++) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return "Executed";
}
#Override
protected void onPostExecute(String result) {
// runs on UI thread and updated UI after executing doInBackground
progressDialog.dismiss();
}
#Override
protected void onPreExecute() {
ProgressDialog progressDialog = ProgressDialog.show(MainActivity.this, "Title ", "Loading...");
progressDialog.show();
}
#Override
protected void onProgressUpdate(Void... values) {
// runs on UI thread and starts first
}
}

Android Async task porgress bar doesn't comes until background process is completed

I am building a project in which i use async task to show progress bar.
I am using get() method to wait the main thread so we can do the other task before .
but progress bar is showing after completion of doInBackground thered.
I Want to show the loading bar when the loading starts.
It will dismiss when onPostExecute calls.
public class TempConverterActivity extends Activity {
pojo p;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button b= (Button) findViewById(R.id.btn);
b.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
showResult();
}
});
}
private void showResult() {
try {
new LoadData().execute().get();
} catch (Exception e) {
Log.e("async brix--", e.getMessage());
}
runned();
}
private void runned() {
ArrayList<String> al = p.getData();
for (String str : al){
Toast.makeText(getApplicationContext(), str, Toast.LENGTH_SHORT).show();
}
}
private class LoadData extends AsyncTask<Void, Void, Void> {
private final ProgressDialog dialog = new ProgressDialog(TempConverterActivity.this);
protected void onPreExecute() {
dialog.setMessage("Loading data...");
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.show();
}
protected void onPostExecute(final Void unused) {
if (dialog.isShowing()) {
dialog.dismiss();
}
}
#Override
protected Void doInBackground(Void... params) {
p = new pojo();
new SoapParser(p);
return null;
}
}}
Please help . Thanks in advance.

You can try following code,
progDailog = ProgressDialog.show(loginAct,"Process ", "please wait....",true,true);
new Thread ( new Runnable()
{
public void run()
{
// your code goes here
}
}).start();
Handler progressHandler = new Handler()
{
public void handleMessage(Message msg1)
{
progDailog.dismiss();
}
}

Edited: In my previous answer I suggested using a Handler; however, AsyncTask eliminates the need to do this which I didn't spot.
Why do you feel the need to call AsyncTask.get()? This is a blocking call, and you call this from the UI thread, thus it is ultimately a race condition as to whether it or onPreExecute() is run first.
I see no reason why you should call get() in this context. You want to call runned() after the AsyncTask completes, but you could do this by launching a new thread from onPostExecute(). Alternatively you could do as you do now, using get(), but call that from a new thread instead of the UI thread.

Alert box goes away on cancel but comes back again to haunt?

All i want to do is display a text for 1000 milliseconds and get the next thing.. dialogs are slow to pop up so i used a textview..but its not working.. the code snippet is given..
What am I doing wrong?
Thread sleep_for_sometime = new Thread() {
public void run() {
try {
correct.setVisibility(TextView.VISIBLE);
sleep(1000);
correct.setVisibility(TextView.INVISIBLE);
} catch (InterruptedException e) {
e.printStackTrace();
}
finally {
get_question(questionset[i]);
}
}
};
//sleep_for_sometime.setDaemon(false);
sleep_for_sometime.start();

You should change visibility in UI thread. Read painless threading

AsyncTask is great, but overused in some ways I think. Just use post/postDelayed. You're not really doing background work, you just want to delay some UI-thread work. Definitely read Nikita's link, but I would do something like:
correct.setVisibility(View.VISIBLE);
correct.postDelayed(new Runnable() {
correct.setVisibility(View.INVISIBLE);
get_question(questionset[i]);
}, 1000);

Expanding Nikita's Answer , you could do something like this
private class SleepTask extends AsyncTask<Void,Integer,Void> {
#Override
protected Void doInBackground(Void... params) {
try {
publishProgress(0);
sleep(1000);
publishProgress(1);
}catch(Exception e){
//null
}
}
#Override
protected void onProgressUpdate(Integer... i){
if(i[0]==0){
correct.setVisibility(TextView.VISIBLE);
}else{
correct.setVisibility(TextView.INVISIBLE);
}
}
#Override
protected void onPostExecute(Void res) {
get_question(questionset[i]);
}
#Override
protected void onPreExecute() {
//do something before execution
}
}
to start the thread , do this
new SleepTask().execute();