I have a thrad that calls a function that populates a list in an activity, I would put a progressDialog when the function is running, I wonder what I do to change the progress dialog is invoked when the activity is called, follows current code :
new Thread(){
public void run() {
runOnUiThread(new Runnable() {
#Override
public void run() {
loadList();
}
});
}
}.start();
I think you would be better off using an AsyncTask, easy to attach a progress dialog to this.
Here's an example: http://droidapp.co.uk/?p=177
Create and start your progress dialog in the UI-Thread, then start your Thread. Create a Runnable object which dissmiss() your progress. Invoke this Runnable when you finished populating your list with runOnUiThread.
Related
In my android application, dialog's showing up takes a time. At that time I want to show progress dialog. I learned that the progress dialog should be executed in thread but when I use a thread it gives an error.
I created progress dialog in oncreate method and tried to show in my button's onclick method.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
context = getApplicationContext();
mProgressDialog = new ProgressDialog(context, R.style.StyledDialog);
mProgressDialog.setCanceledOnTouchOutside(false);
Drawable drawable = context.getResources().getDrawable(R.drawable.progress_dialog);
mProgressDialog.setProgressDrawable(drawable);
}
Following code is my button's onclick method which is defined in xml file like : android:onClick="refList"
public void refList(View v) {
Thread t = new Thread(new Runnable() {
#Override
public void run() {
mProgressDialog.show();
}
});
t.start();
if(!refListDialog.isShowing()) {
refListDialog.show();
t.interrupt();
}
}
This is the exception:
FATAL EXCEPTION: Thread-27305 java.lang.RuntimeException: Can't create handler inside thread that has not called Looper.prepare()
at android.os.Handler.<init>(Handler.java:121)
at android.view.ViewRootImpl$ViewRootHandler.<init>(ViewRootImpl.java:3052)
at android.view.ViewRootImpl.<init>(ViewRootImpl.java:3321)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:294)
at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:226)
at android.view.WindowManagerImpl$CompatModeWrapper.addView(WindowManagerImpl.java:151)
at android.app.Dialog.show(Dialog.java:277)
at gcm.b4deploy.com.hesapozeti.MainActivity$2.run(MainActivity.java:196)
at java.lang.Thread.run(Thread.java:856)
I am really stuck and waiting ideas. Thanks in advance.
I really don't get the idea why you put the progressDialog inside a thread.
yourProgress = new ProgressDialog(this);
yourProgress.setTitle("Title");
yourProgress.setMessage("wait for a while"); yourProgress.getProcess();
yourProgress.show();
Put this code first in your function in the onClick method. It will execute sequentially.And you can make conditional statement, and if done, call yourProgress.dismiss();
- add your statement above the progressDialog.setTitle. I suggest you declare the progress dialog outside this method, so that you can dismiss that one in the other method which return true. Just remove those runnable thing.
Try like this
runOnUiThread(new Runnable() {
public void run() {
mProgressDialog.show();
}
});
How can I make this happend?
Thread t = new Thread(new Runnable() {
#Override
public void run() {
FacebookConnectTask task =
new FacebookConnectTask("facebookId", "token", "email", facebookGender,0, 0);
task.setOnPreExecuteListener(this);
task.setOnDoneListener(this);
task.execute();
}
});
t.start();
public void onPreExecute() {
progressbar.setVisibility(View.VISIBLE);
}
public void onDone() {
progressbar.setVisibility(View.GONE);
}
Since I am opening a new thread, I can not change a UI element in it, so, How can I manage to do something to the UI, when the task starts and when it's finished?
You could do the work in an AyncTask. The AsyncTask executes everything in doInBackground() inside of another thread, which does not have access to the GUI where your views are.
preExecute() and postExecute() offer you access to GUI before and after the heavy lifting occurs in this new thread, you can even pass the result of the long operation to postExecute() to then show any results of processing.
More here: http://developer.android.com/reference/android/os/AsyncTask.html
Example here: http://www.vogella.com/articles/AndroidPerformance/article.html
inside your activity
private Handler myHandler=new Handler();
next in your on done callback
public void onDone() {
myHandler.post(new Runnable(){
#Override
public void run() {
progressbar.setVisibility(View.GONE)
}
})
}
But as already was said. AsyncTask is more siutable for it
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..
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.
I need to display a message to the user "Communicating to the Server...Please wait for few seconds" when a call to a webservice is made. Currently I'm using Toast.makeText to display the message. For some reason, I don't see the message pop-up. But interestingly when I comment the web service method call, I see the Toast message.
Toast.makeText(this, "Communicating to the Server...Please wait for few seconds",
Toast.LENGTH_SHORT).show();
//webservice code goes here...
Or any other alternative to satisfy this requirement is also fine.
Have you looked at using AysncTask. Using AsyncTask you can show a dialog with your message on onPreExecute().
Do NOT mix UI code and network code. See: http://developer.android.com/resources/articles/painless-threading.html
You can use AsyncTask to run your service and show Toast in onPreExecute.
Or you can use normal Thread but, you'll need to use Handler. Here is how:
class MyActivity extends Activity
{
final Handler mHandler;
#Override
public void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(...);
mHandler = new Handler();
...
}
void showToast(final String text)
{
mHandler.post(new Runnable()
{
#Override
public void run()
{
Toast.makeText(MyActivity.this, text, Toast.LENGTH_LONG).show();
}
});
}
class MyThread implements Runnable
{
#Override
public void run()
{
showToast("your custom text");
//your service code
}
}
}
And here is how you start the thread:
Thread thread = new Thread(new MyThread());
thread.run();
The problem is that the UI thread is blocked as soon as you make the blocking web service call, so it never updates with the toast message. By the time it returns, the time for toast message has expired.
Run your web service call in a thread, using AsyncTask, or just create a thread like,
new Thread(new Runnable() {
public void run() {
// WS call here
}
}).start();
Take care that if you create your own thread, you can only update the UI from the UI thread, so you'll need to use Handler.post() or sendMessage() to run the UI update on the UI thread.
http://developer.android.com/reference/android/os/AsyncTask.html
http://developer.android.com/reference/android/os/Handler.html