I get this error "Can't create handler inside thread that has not called Looper.prepare()"
Can you tell me how to fix it?
public class PaymentActivity extends BaseActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.payment);
final Button buttonBank = (Button) findViewById(R.id.buttonBank);
buttonBank.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
progressDialog = ProgressDialog.show(PaymentActivity.this, "",
"Redirecting to payment gateway...", true, true);
new Thread() {
public void run() {
try {
startPayment("Bank");
} catch (Exception e) {
alertDialog.setMessage(e.getMessage());
handler.sendEmptyMessage(1);
progressDialog.cancel();
}
}
}.start();
}
});
StartPayment Method:
private void startPayment(String id) {
Bundle b = getIntent().getExtras();
final Sail sail = b.getParcelable(Constant.SAIL);
final Intent bankIntent = new Intent(this, BankActivity.class);
try {
Reservation reservation = RestService.createReservation(
sail.getId(),
getSharedPreferences(Constant.PREF_NAME_CONTACT, 0));
bankIntent.putExtra(Constant.RESERVATION, reservation);
// <workingWithDB> Storing Reservation info in Database
DBAdapter db = new DBAdapter(this);
db.open();
#SuppressWarnings("unused")
long rowid;
rowid = db.insertRow(sail.getId(), sail.getFrom(),
sail.getTo(), sail.getShip(), sail.getDateFrom().getTime(),
sail.getPrice().toString(), reservation.getId().floatValue());
db.close();
// </workingWithDB>
String html = PaymentService.getRedirectHTML(id, reservation);
bankIntent.putExtra(Constant.BANK, html);
} catch (Exception e) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
AlertDialog alertDialog = builder.create();
alertDialog.setMessage(e.getMessage());
alertDialog.show();
}
startActivity(bankIntent);
}
You should know that when you try to modify your UI , the only thread who can do that is the UiThread.
So if you want to modify your UI in another thread, try to use the method: Activity.runOnUiThread(new Runnable);
Your code should be like this :
new Thread() {
public void run() {
YourActivity.this.runOnUiThread(new Runnable(){
#Override
public void run(){
try {
startPayment("Bank");//Edit,integrate this on the runOnUiThread
} catch (Exception e) {
alertDialog.setMessage(e.getMessage());
handler.sendEmptyMessage(1);
progressDialog.cancel();
}
});
}
}
}.start();
I assume you create a Handler in startPayment() method. You can't do that, as handlers can be created on th UI thread only. Just create it in your activity class.
Instead of new Thread() line, try giving
this.runOnUiThread(new Runnable() {
you cant change any UI in thread you can use runOnUIThread or AsyncTask for more detail about this click here
I've found that most thread handling can be replaced by AsyncTasks like this:
public class TestStuff extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button buttonBank = (Button) findViewById(R.id.button);
buttonBank.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
new StartPaymentAsyncTask(TestStuff.this).execute((Void []) null);
}
});
}
private class StartPaymentAsyncTask extends AsyncTask<Void, Void, String> {
private ProgressDialog dialog;
private final Context context;
public StartPaymentAsyncTask(Context context) {
this.context = context;
}
#Override
protected void onPreExecute() {
dialog = new ProgressDialog(context);
// setup your dialog here
dialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
dialog.setMessage(context.getString(R.string.doing_db_work));
dialog.setCancelable(false);
dialog.show();
}
#Override
protected String doInBackground(Void... ignored) {
String returnMessage = null;
try {
startPayment("Bank");
} catch (Exception e) {
returnMessage = e.getMessage();
}
return returnMessage;
}
#Override
protected void onPostExecute(String message) {
dialog.dismiss();
if (message != null) {
// process the error (show alert etc)
Log.e("StartPaymentAsyncTask", String.format("I received an error: %s", message));
} else {
Log.i("StartPaymentAsyncTask", "No problems");
}
}
}
public void startPayment(String string) throws Exception {
SystemClock.sleep(2000); // pause for 2 seconds for dialog
Log.i("PaymentStuff", "I am pretending to do some work");
throw new Exception("Oh dear, database error");
}
}
I pass in the Application Context to the Async so it can create dialogs from it.
The advantage of doing it this way is you know exactly which methods are run in your UI and which are in a separate background thread. Your main UI thread isn't delayed, and the separation into small async tasks is quite nice.
The code assumes your startPayment() method does nothing with the UI, and if it does, move it into the onPostExecute of the AsyncTask so it's done in the UI thread.
Try
final Handler handlerTimer = new Handler(Looper.getMainLooper());
handlerTimer.postDelayed(new Runnable() {
public void run() {
......
}
}, time_interval});
Related
I have to update the list after optimizing the running apps ....
m_optimizeBtn.setOnClickListener(new View.OnClickListener()
{
#Override
public void onClick(View v)
{
launchProgressRing(OptimizationActivity.this);
listAdaptor.notifyDataSetChanged();
}
});
}
Killing the running process in a seprate thread....
public void launchProgressRing(Context ctx){
final ProgressDialog opt_proDialog=new ProgressDialog(ctx);
opt_proDialog.setTitle("Please wait...");
opt_proDialog.setMessage("Optimizing power draining apps...");
opt_proDialog.setIndeterminate(true);
opt_proDialog.show();
opt_proDialog.setCancelable(false);
new Thread(new Runnable()
{
#Override
public void run()
{
//TODO: optimize apps
m_cPowerDrainingApps.killBgRunningProcesses(runningAppsList);
try
{
Thread.sleep(1500);
} catch (InterruptedException e)
{
e.printStackTrace();
}
runOnUiThread(new Runnable()
{
#Override
public void run()
{
opt_proDialog.dismiss();
}
});
}
}).start();
}
listAdaptor.notifyDataSetChanged() is not working ,don't know why ???
What I suggest is to use AsyncTask to do the job. AsyncTask has two good methods for you:
doInBackground: which you can put most of the background tasks in there
onPostExecute : which you can put the logic of what needs to be done when the background task has finished its job.
So your code should look like this:
public class BackgroundTask extends AsyncTask<Void,Void,Void>{
private ListAdapter mAdapter;
public BackgroundTask(ListAdapter adapter)
{
mAdapter = adapter
}
public Void doInBackground (Void... params)
{
//define m_cPowerDrainingApps somewhere
m_cPowerDrainingApps.killBgRunningProcesses(runningAppsList);
try
{
Thread.sleep(1500);
} catch (InterruptedException e)
{
e.printStackTrace();
}
}
public Void onPostExecute (Void... params)
{
//do your UI things
mAdapter.notifyDataSetChanged();
}
}
and then run this with:
new BackgroundTask(listAdapter).execute()
Use a Handler and its postDelayed method to invalidate the list's adapter as follows:
final Handler handler = new Handler()
handler.postDelayed( new Runnable() {
#Override
public void run() {
adapter.notifyDataSetChanged();
handler.postDelayed( this, 60 * 1000 );
}
}, 60 * 1000 );
You must only update UI in the main (UI) thread.
I am new to android programming. I am developing a web crawler for which i am using a Async Task and it is working well.In order to keep user informed,i am using progress dialog. My problem is,if i use a Progress Dialog my program takes more time to execute and when i won`t use the progress dialog,it executes faster.
Done Work
OnCreate Method
protected void onCreate(Bundle savedInstanceState) {
try {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_results);
Intent intent = getIntent();
s1 = intent.getStringExtra("Number1");
s2 = intent.getStringExtra("Number2");
s3=intent.getIntExtra("selectedItem",0);
HttpAsyncTask asyncTask = new HttpAsyncTask();
asyncTask.execute();
}catch (Exception e)
{
messageBox("Exception",e.getMessage());
}
}
Async Task Class
private class HttpAsyncTask extends AsyncTask<List<String>, Integer, List<String>> {
private ProgressDialog dialog;
#Override
protected void onPreExecute()
{
dialog = new ProgressDialog(Results.this);
dialog.setIndeterminate(true);
dialog.setMessage("Please Wait");
dialog.setCancelable(true);
dialog.show();
super.onPreExecute();
}
#Override
protected List<String> doInBackground(List<String>... urls) {
//android.os.Debug.waitForDebugger();
// spinner.setVisibility(View.VISIBLE);
List<String>resultList=new ArrayList<String>();
try
{
if(isCancelled())
return resultList;
resultList=WebCrawlerClass.GetPost(s1,s2,s3);
}catch (Exception e)
{
messageBoxs("Error", e.getMessage());
}
return resultList;
}
// onPostExecute displays the results of the AsyncTask.
#Override
protected void onPostExecute(List<String> result)
{
if(dialog.isShowing())
{
dialog.dismiss();
}
if(s3 == 2)
{
docListAdapter=new ListViewData(Results.this,result);
}
else {
docListAdapter = new NameNumListData(Results.this, result);
}
docList=(ListView)findViewById(R.id.listView2);
docList.setAdapter(docListAdapter);
super.onPostExecute(result);
}
#Override
protected void onCancelled() {
super.onCancelled();
this.cancel(true);
}
}
Am I missing something? Need help..
Thanks and Regards,
Abhinav
In you activity
// Start the progress dialog
..
Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
// dismiss the progress dialog
}
};
HttpAsyncTask asyncTask = new HttpAsyncTask(handler);
asyncTask.execute();
In your asynctask class
private class HttpAsyncTask extends AsyncTask<List<String>, Integer, List<String>> {
private Handler handler = null;
public HttpAsyncTask (Handler handler) {
this.handler = handler;
}
protected Void doInBackground(Void... params) {
//Perform your task
// When you know that task is finished , fire following code
if (null != handler) {
Message message = handler.obtainMessage();
message.obj = Any data you want to sent to the activity
message.what = 1 ; ( Optional )
handler.sendMessage(message);
}
}
Thus when sendMessage function is called from doInbackground.. your handleMessage in your activity will get triggered and then you should dismiss the progress dialog
Hope this will improve the performance issue what you are facing
Remove super.onPreExecute(); in onPreExecute() method and check .It might Help
I was having some problem for Android activity transition. Basically what I am trying to do is share text to Twitter. However, when I open up the twitter content, it took quite a few seconds to load up the content and resulting in the white blank activity for a few seconds.
And here is my codes, when my button onClick, I am executing the loading dialog:
ivTwitterShare.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Thread newThread = new Thread() {
#Override
public void run() {
try {
super.run();
sleep(10000);
} catch (Exception e) {
} finally {
Intent intent = new Intent(Intent.ACTION_VIEW, Uri
.parse(tweetUrl));
startActivity(intent);
progressDialog.dismiss();
}
}
};
newThread.start();
new LoadTwitterTask().execute();
}
});
private class LoadTwitterTask extends AsyncTask<Void, Integer, Void> {
#Override
protected void onPreExecute() {
progressDialog = ProgressDialog.show(context, "Loading Twitter...",
"Retrieving Twitter information, please wait...", false,
false);
EventDialogueBox.customizeDialogueBox(context, progressDialog);
}
#Override
protected Void doInBackground(Void... params) {
try {
synchronized (this) {
int counter = 0;
while (counter <= 4) {
this.wait(50);
counter++;
publishProgress(counter * 25);
}
}
} catch (InterruptedException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onProgressUpdate(Integer... values) {
progressDialog.setProgress(values[0]);
}
#Override
protected void onPostExecute(Void result) {
}
}
However, my problem now is the white blank page before the content is loaded up still there. What I wanted is firstly, the loading dialog will show. Then, at the same time, the twitter intent is loading. Once finish loaded up the content, then dialog will be dismissed.
Any ideas?
Thanks in advance.
I am trying to put a progressDialog in my fragment so my app feels smoother between each actions. The problem that I have is that the main thread is returning the view before the async thread has modified it. I was doing a Thread.join() before switching to this methode.
public class MyFragment extends Fragment {
public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle args) {
mLLayout = new LinearLayout(getActivity());
mLLayout.setPadding(0, 0, 0, 0);
mLLayout.setOrientation(LinearLayout.VERTICAL);
mScroll = new ScrollView(getActivity().getApplicationContext());
mScroll.setVerticalScrollBarEnabled(true);
mScroll.addView(mLLayout);
new AsyncCaller().execute();
return mScroll;
}
private class AsyncCaller extends AsyncTask<Void, Void, Void>
{
ProgressDialog nDialog = new ProgressDialog(getActivity());
#Override
protected void onPreExecute()
{
super.onPreExecute();
//this method will be running on UI thread
nDialog = new ProgressDialog(getActivity());
nDialog.setMessage("Loading..");
nDialog.setTitle("Checking Network");
nDialog.setIndeterminate(false);
nDialog.setCancelable(true);
nDialog.show();
}
#Override
protected Void doInBackground(Void... params)
{
//Doing http requests and modifying views
return null;
}
#Override
protected void onPostExecute(Void result)
{
super.onPostExecute(result);
//this method will be running on UI thread
nDialog.dismiss();
}
}
...
}
I cant find a solution without blocking the main thread and by the same way not seeing the progressDialog at all and having a big lag instead. Also, I never saw my code go into "onPostExecute()".
Thanks in advance for your help!
Striaght from an app i've done, this code should help:
ProgressBar mProgress = (ProgressBar) findViewById(R.id.progressBar);
private float mProgressStatus = 0;
private Handler mHandler = new Handler();
private void startProgressBar()
{
new Thread(new Runnable()
{
#Override
public void run()
{
while (mProgressStatus < 100)
{
try
{
Thread.sleep(1000);
}
catch (InterruptedException e)
{
e.printStackTrace();
}
mProgressStatus += 1.3;
mHandler.post(new Runnable()
{
#Override
public void run()
{
mProgress.setProgress((int) mProgressStatus);
}
});
}
}
}).start();
}
I push a web service call in my activity to a thread (shown below). The first time I do this in the activity it works fine (gets the text from my edittext and loads the service to get lat/lng data)
But when I click the back button (emulator) and try to fire off this thread a second time it blows up after the .start(); in my click handler. What might I be doing wrong here? thanks
private Thread getLocationByZip = new Thread() {
public void run() {
try {
EditText filterText = (EditText) findViewById(R.id.zipcode);
Editable zip = filterText.getText();
LocationLookupService locationLookupService = new LocationLookupService();
selectedLocation = locationLookupService.getLocationByZip(zip.toString());
locationHandler.post(launchFindWithLocationInfo);
} catch (Exception e) {
}
}
};
private Runnable launchFindWithLocationInfo = new Runnable() {
#Override
public void run() {
try {
Intent abc = new Intent(LocationLookup.this, FindWithLocation.class);
startActivity(abc);
} catch (Exception e) {
}
}
};
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.location);
locationHandler = new Handler();
findViewById(R.id.findbyzip).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
getLocationByZip.start();
}
});
}
Update
After the great advice I went with an AsyncTask so if anyone finds this going forward the above thread/handler model looks something like the below as an asynctask
private class LocationLookupTask extends AsyncTask<String, Void, Location> {
private ProgressDialog dialog;
#Override
protected void onPreExecute() {
this.dialog = ProgressDialog.show(LocationLookup.this, "", "Loading...");
}
#Override
protected Location doInBackground(String... zips) {
Location selectedLocation = null;
for (String zip : zips) {
LocationLookupService locationLookupService = new LocationLookupService();
selectedLocation = locationLookupService.getLocationByZip(zip);
}
return selectedLocation;
}
#Override
protected void onPostExecute(Location location) {
this.dialog.dismiss();
((AppDelegate) getApplicationContext()).setSelectedLocation(location);
Intent abc = new Intent(LocationLookup.this, FindWithLocation.class);
startActivity(abc);
}
}
Now to call this in the onclick you would do this
findViewById(R.id.findbyzip).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
EditText filterText = (EditText) findViewById(R.id.zipcode);
Editable zip = filterText.getText();
LocationLookupTask task = new LocationLookupTask();
task.execute(new String[]{zip.toString()});
}
});
You can't start a thread twice:
It is never legal to start a thread more than once.
Taken from Thread.start().
So, you need to create a new thread and start that one.
You can not call twice the start method of the Thread class, I suggest you also control the logic within the method onCreate since according to the life cycle of an Activity that method may be called by Android lifecycle Activity Manager.
Furthermore i suggest you to avoid this approach and consider to use the AsyncTask provided by the Android SDK.
http://developer.android.com/reference/android/os/AsyncTask.html
If you really want to do this without creating a new class or using AsyncTask, you could just make a method to get a new Thread on each call:
private Thread getLocationByZip;
private void getLocation() {
getLocationByZip = new Thread() {
public void run() {
try {
EditText filterText = (EditText) findViewById(R.id.zipcode);
Editable zip = filterText.getText();
LocationLookupService locationLookupService = new LocationLookupService();
selectedLocation = locationLookupService.getLocationByZip(zip.toString());
locationHandler.post(launchFindWithLocationInfo);
} catch (Exception e) {
}
}
};
getLocationByZip.start();
}
Then replace getLocationByZip.start() in your code with getLocation(). However, I agree that an AsyncTask would be a better way to go, though this would work for you.