What does the following exception mean; how can I fix it?
This is the code:
Toast toast = Toast.makeText(mContext, "Something", Toast.LENGTH_SHORT);
This is the exception:
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.widget.Toast.<init>(Toast.java:68)
at android.widget.Toast.makeText(Toast.java:231)
You need to call Toast.makeText(...) from the UI thread:
activity.runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(activity, "Hello", Toast.LENGTH_SHORT).show();
}
});
This is copy-pasted from another (duplicate) SO answer.
You're calling it from a worker thread. You need to call Toast.makeText() (and most other functions dealing with the UI) from within the main thread. You could use a handler, for example.
Look up Communicating with the UI Thread in the documentation. In a nutshell:
// Set this up in the UI thread.
mHandler = new Handler(Looper.getMainLooper()) {
#Override
public void handleMessage(Message message) {
// This is where you do your work in the UI thread.
// Your worker tells you in the message what to do.
}
};
void workerThread() {
// And this is how you call it from the worker thread:
Message message = mHandler.obtainMessage(command, parameter);
message.sendToTarget();
}
Other options:
You could use Activity.runOnUiThread(). Straightforward if you have an Activity:
#WorkerThread
void workerThread() {
myActivity.runOnUiThread(() -> {
// This is where your UI code goes.
}
}
You could also post to the main looper. This works great if all you have is a Context.
#WorkerThread
void workerThread() {
ContextCompat.getMainExecutor(context).execute(() -> {
// This is where your UI code goes.
}
}
Deprecated:
You could use an AsyncTask, that works well for most things running in the background. It has hooks that you can call to indicate the progress, and when it's done.
It's convenient, but can leak contexts if not used correctly. It's been officially deprecated, and you shouldn't use it anymore.
UPDATE - 2016
The best alternative is to use RxAndroid (specific bindings for RxJava) for the P in MVP to take charge fo data.
Start by returning Observable from your existing method.
private Observable<PojoObject> getObservableItems() {
return Observable.create(subscriber -> {
for (PojoObject pojoObject: pojoObjects) {
subscriber.onNext(pojoObject);
}
subscriber.onCompleted();
});
}
Use this Observable like this -
getObservableItems().
subscribeOn(Schedulers.io()).
observeOn(AndroidSchedulers.mainThread()).
subscribe(new Observer<PojoObject> () {
#Override
public void onCompleted() {
// Print Toast on completion
}
#Override
public void onError(Throwable e) {}
#Override
public void onNext(PojoObject pojoObject) {
// Show Progress
}
});
}
----------------------------------------------------------------------------------------------------------------------------------
I know I am a little late but here goes.
Android basically works on two thread types namely UI thread and background thread. According to android documentation -
Do not access the Android UI toolkit from outside the UI thread to fix this problem, Android offers several ways to access the UI thread from other threads. Here is a list of methods that can help:
Activity.runOnUiThread(Runnable)
View.post(Runnable)
View.postDelayed(Runnable, long)
Now there are various methods to solve this problem.
I will explain it by code sample:
runOnUiThread
new Thread()
{
public void run()
{
myactivity.this.runOnUiThread(new Runnable()
{
public void run()
{
//Do your UI operations like dialog opening or Toast here
}
});
}
}.start();
LOOPER
Class used to run a message loop for a thread. Threads by default do
not have a message loop associated with them; to create one, call
prepare() in the thread that is to run the loop, and then loop() to
have it process messages until the loop is stopped.
class LooperThread extends Thread {
public Handler mHandler;
public void run() {
Looper.prepare();
mHandler = new Handler() {
public void handleMessage(Message msg) {
// process incoming messages here
}
};
Looper.loop();
}
}
AsyncTask
AsyncTask allows you to perform asynchronous work on your user
interface. It performs the blocking operations in a worker thread and
then publishes the results on the UI thread, without requiring you to
handle threads and/or handlers yourself.
public void onClick(View v) {
new CustomTask().execute((Void[])null);
}
private class CustomTask extends AsyncTask<Void, Void, Void> {
protected Void doInBackground(Void... param) {
//Do some work
return null;
}
protected void onPostExecute(Void param) {
//Print Toast or open dialog
}
}
Handler
A Handler allows you to send and process Message and Runnable objects
associated with a thread's MessageQueue.
Message msg = new Message();
new Thread()
{
public void run()
{
msg.arg1=1;
handler.sendMessage(msg);
}
}.start();
Handler handler = new Handler(new Handler.Callback() {
#Override
public boolean handleMessage(Message msg) {
if(msg.arg1==1)
{
//Print Toast or open dialog
}
return false;
}
});
Toast.makeText() can only be called from Main/UI thread. Looper.getMainLooper() helps you to achieve it:
JAVA
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
// write your code here
}
});
KOTLIN
Handler(Looper.getMainLooper()).post {
// write your code here
}
An advantage of this method is that you can run UI code without Activity or Context.
Try this, when you see runtimeException due to Looper not prepared before handler.
Handler handler = new Handler(Looper.getMainLooper());
handler.postDelayed(new Runnable() {
#Override
public void run() {
// Run your task here
}
}, 1000 );
I ran into the same problem, and here is how I fixed it:
private final class UIHandler extends Handler
{
public static final int DISPLAY_UI_TOAST = 0;
public static final int DISPLAY_UI_DIALOG = 1;
public UIHandler(Looper looper)
{
super(looper);
}
#Override
public void handleMessage(Message msg)
{
switch(msg.what)
{
case UIHandler.DISPLAY_UI_TOAST:
{
Context context = getApplicationContext();
Toast t = Toast.makeText(context, (String)msg.obj, Toast.LENGTH_LONG);
t.show();
}
case UIHandler.DISPLAY_UI_DIALOG:
//TBD
default:
break;
}
}
}
protected void handleUIRequest(String message)
{
Message msg = uiHandler.obtainMessage(UIHandler.DISPLAY_UI_TOAST);
msg.obj = message;
uiHandler.sendMessage(msg);
}
To create the UIHandler, you'll need to perform the following:
HandlerThread uiThread = new HandlerThread("UIHandler");
uiThread.start();
uiHandler = new UIHandler((HandlerThread) uiThread.getLooper());
Hope this helps.
Reason for an error:
Worker threads are meant for doing background tasks and you can't show anything on UI within a worker thread unless you call method like runOnUiThread. If you try to show anything on UI thread without calling runOnUiThread, there will be a java.lang.RuntimeException.
So, if you are in an activity but calling Toast.makeText() from worker thread, do this:
runOnUiThread(new Runnable()
{
public void run()
{
Toast toast = Toast.makeText(getApplicationContext(), "Something", Toast.LENGTH_SHORT).show();
}
});
The above code ensures that you are showing the Toast message in a UI thread since you are calling it inside runOnUiThread method. So no more java.lang.RuntimeException.
that's what i did.
new Handler(Looper.getMainLooper()).post(new Runnable() {
#Override
public void run() {
Toast(...);
}
});
Visual components are "locked" to changes from outside threads.
So, since the toast shows stuff on the main screen that is managed by the main thread, you need to run this code on that thread.
Hope that helps:)
I was getting this error until I did the following.
public void somethingHappened(final Context context)
{
Handler handler = new Handler(Looper.getMainLooper());
handler.post(
new Runnable()
{
#Override
public void run()
{
Toast.makeText(context, "Something happened.", Toast.LENGTH_SHORT).show();
}
}
);
}
And made this into a singleton class:
public enum Toaster {
INSTANCE;
private final Handler handler = new Handler(Looper.getMainLooper());
public void postMessage(final String message) {
handler.post(
new Runnable() {
#Override
public void run() {
Toast.makeText(ApplicationHolder.INSTANCE.getCustomApplication(), message, Toast.LENGTH_SHORT)
.show();
}
}
);
}
}
runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(mContext, "Message", Toast.LENGTH_SHORT).show();
}
});
Wonderful Kotlin solution:
runOnUiThread {
// Add your ui thread code here
}
first call Looper.prepare() and then call Toast.makeText().show() last call Looper.loop() like:
Looper.prepare() // to be able to make toast
Toast.makeText(context, "not connected", Toast.LENGTH_LONG).show()
Looper.loop()
This is because Toast.makeText() is calling from a worker thread. It should be call from main UI thread like this
runOnUiThread(new Runnable() {
public void run() {
Toast toast = Toast.makeText(mContext, "Something", Toast.LENGTH_SHORT);
}
});
The answer by ChicoBird worked for me. The only change I made was in the creation of the UIHandler where I had to do
HandlerThread uiThread = new HandlerThread("UIHandler");
Eclipse refused to accept anything else. Makes sense I suppose.
Also the uiHandler is clearly a class global defined somewhere. I still don't claim to understand how Android is doing this and what is going on but I am glad it works. Now I will proceed to study it and see if I can understand what Android is doing and why one has to go through all these hoops and loops. Thanks for the help ChicoBird.
For Rxjava and RxAndroid User:
public static void shortToast(String msg) {
Observable.just(msg)
.observeOn(AndroidSchedulers.mainThread())
.subscribe(message -> {
Toast.makeText(App.getInstance(), message, Toast.LENGTH_SHORT).show();
});
}
Coroutine will do it perfectly
CoroutineScope(Job() + Dispatchers.Main).launch {
Toast.makeText(context, "yourmessage",Toast.LENGTH_LONG).show()}
I was running into the same issue when my callbacks would try to show a dialog.
I solved it with dedicated methods in the Activity - at the Activity instance member level - that use runOnUiThread(..)
public void showAuthProgressDialog() {
runOnUiThread(new Runnable() {
#Override
public void run() {
mAuthProgressDialog = DialogUtil.getVisibleProgressDialog(SignInActivity.this, "Loading ...");
}
});
}
public void dismissAuthProgressDialog() {
runOnUiThread(new Runnable() {
#Override
public void run() {
if (mAuthProgressDialog == null || ! mAuthProgressDialog.isShowing()) {
return;
}
mAuthProgressDialog.dismiss();
}
});
}
Java 8
new Handler(Looper.getMainLooper()).post(() -> {
// Work in the UI thread
});
Kotlin
Handler(Looper.getMainLooper()).post{
// Work in the UI thread
}
GL
Handler handler2;
HandlerThread handlerThread=new HandlerThread("second_thread");
handlerThread.start();
handler2=new Handler(handlerThread.getLooper());
Now handler2 will use a different Thread to handle the messages than the main Thread.
To display a dialog or a toaster in a thread, the most concise way is to use the Activity object.
For example:
new Thread(new Runnable() {
#Override
public void run() {
myActivity.runOnUiThread(new Runnable() {
public void run() {
myActivity.this.processingWaitDialog = new ProgressDialog(myActivity.this.getContext());
myActivity.this.processingWaitDialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
myActivity.this.processingWaitDialog.setMessage("abc");
myActivity.this.processingWaitDialog.setIndeterminate(true);
myActivity.this.processingWaitDialog.show();
}
});
expenseClassify.serverPost(
new AsyncOperationCallback() {
public void operationCompleted(Object sender) {
myActivity.runOnUiThread(new Runnable() {
public void run() {
if (myActivity.this.processingWaitDialog != null
&& myActivity.this.processingWaitDialog.isShowing()) {
myActivity.this.processingWaitDialog.dismiss();
myActivity.this.processingWaitDialog = null;
}
}
}); // .runOnUiThread(new Runnable()
...
Using lambda:
activity.runOnUiThread(() -> Toast.makeText(activity, "Hello", Toast.LENGTH_SHORT).show());
Toast, AlertDialogs needs to run on UI thread, you can use Asynctask to use them properly in android development.but some cases we need to customize the time outs, so we use Threads, but in threads we cannot use Toast,Alertdialogs like we using in AsyncTask.So we need separate Handler for popup those.
public void onSigned() {
Thread thread = new Thread(){
#Override
public void run() {
try{
sleep(3000);
Message message = new Message();
message.what = 2;
handler.sendMessage(message);
} catch (Exception e){
e.printStackTrace();
}
}
};
thread.start();
}
in Above example i want to sleep my thread in 3sec and after i want to show a Toast message,for that in your mainthread implement handler.
handler = new Handler() {
public void handleMessage(Message msg) {
switch(msg.what){
case 1:
Toast.makeText(getActivity(),"cool",Toast.LENGTH_SHORT).show();
break;
}
super.handleMessage(msg);
}
};
I used switch case here, because if you need to show different message in same way, you can use switch case within Handler class...hope this will help you
This usually happens when something on the main thread is called from any background thread. Lets look at an example , for instance.
private class MyTask extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... voids) {
textView.setText("Any Text");
return null;
}
}
In the above example , we are setting text on the textview which is in the main UI thread from doInBackground() method , which operates only on a worker thread.
I had the same problem and I fixed it simply by putting the Toast in onPostExecute() override function of the Asynctask<> and it worked.
You need to create toast on UI thread. Find the example below.
runOnUiThread(new Runnable() {
public void run() {
Toast.makeText(activity, "YOUR_MESSAGE", Toast.LENGTH_SHORT).show();
}
});
For displaying Toast message please refer to this article
Here is the solution for Kotlin using Coroutine:
Extend your class with CoroutineScope by MainScope():
class BootstrapActivity : CoroutineScope by MainScope() {}
Then simply do this:
launch {
// whatever you want to do in the main thread
}
Don't forget to add the dependencies for coroutine:
org.jetbrains.kotlinx:kotlinx-coroutines-core:${Versions.kotlinCoroutines}
org.jetbrains.kotlinx:kotlinx-coroutines-android:${Versions.kotlinCoroutines}
Create Handler outside the Thread
final Handler handler = new Handler();
new Thread(new Runnable() {
#Override
public void run() {
try{
handler.post(new Runnable() {
#Override
public void run() {
showAlertDialog(p.getProviderName(), Token, p.getProviderId(), Amount);
}
});
}
}
catch (Exception e){
Log.d("ProvidersNullExp", e.getMessage());
}
}
}).start();
Recently, I encounter this problem - It was happening because I was trying to call a function that was to do some UI stuff from the constructor. Removing the initialization from the constructor solved the problem for me.
I got the same problem and this code is working fine for me now.
As an example this is my code to do a task in the background and UI thread.
Observe how the looper is used:
new Thread(new Runnable() {
#Override
public void run() {
Looper.prepare();
// your Background Task here
runOnUiThread(new Runnable() {
#Override
public void run() {
// update your UI here
Looper.loop();
}
});
}
}).start();
i use the following code to show message from non main thread "context",
#FunctionalInterface
public interface IShowMessage {
Context getContext();
default void showMessage(String message) {
final Thread mThread = new Thread() {
#Override
public void run() {
try {
Looper.prepare();
Toast.makeText(getContext(), message, Toast.LENGTH_LONG).show();
Looper.loop();
} catch (Exception error) {
error.printStackTrace();
Log.e("IShowMessage", error.getMessage());
}
}
};
mThread.start();
}
}
then use as the following:
class myClass implements IShowMessage{
showMessage("your message!");
#Override
public Context getContext() {
return getApplicationContext();
}
}
I am running an AsyncTask and it is taking a little time to load. In that period of time, if I am pressing back button then it does not respond. It responds only after a few seconds. So how can I kill or pause or override AsyncTask to go back? Or is there any other way to do something similar?
if (mainContent != null) {
mainContent.post(new Runnable() {
#Override
public void run() {
Bitmap bmp = Utilities.getBitmapFromView(mainContent);
BlurFilter blurFilter = new BlurFilter();
Bitmap blurredBitmap = blurFilter.fastblur(bmp,1,65);
asyncTask = new ConvertViews(blurredBitmap);
asyncTask.execute();
}
});
My AsyncTask:
class ConvertViews extends AsyncTask<Void,Void,Void> {
private Bitmap bmp;
public ConvertViews(Bitmap bmp){
this.bmp = bmp;
}
#Override
protected Void doInBackground(Void... params) {
try {
//Thread.sleep(200);
if(mainViewDrawable == null) {
mainViewDrawable = new BitmapDrawable(getResources(), bmp);
}
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
}
My onBackPressed():
public void onBackPressed() {
super.onBackPressed();
asyncTask.cancel(true);
finish();
}
there is no way that you can stop a asynch task instantly.Every AsynchTask has a boolean flag property associated with it so if cancel_flag =True mean task has been canceled and there is a cancel() function which can be called on aasynchtask object like this
loginTask.cancel(true);
but all this cancel() function does is ,it will set a cancel boolean(flag ) property of asynch task to True so , you can check this property with isCancelled() function inside doInBackGround and do something ,like
protected Object doInBackground(Object... x) {
while (/* condition */) {
// work...
if (isCancelled()) break;
}
return null;
}
and if it is True then you can use break the loops(if you are doing a long task) or return to go quickly out of doInBackground and calling cancel() on asynchtask will skip the execution of onPostExecute().
and the other option is ,if you want to stop multiple running asynch task in background then calling cancel on each one can be tedious so in this case you can have a boolean flag in container class(of asynchtask) and skip the working inside asynchtask if the flag has been set to True ,like
protected Object doInBackground(Object... x) {
while (/* condition */) {
// work...
if (container_asynch_running_flag) break;
}
return null;
}
but make sure to also put a check in onpostExecute in this case because it won't stop the execution of onpost.
You can stop it instantly calling asyncTask.cancel(true).
But it is not recommended to do because it can lead to memory leaks. Better to call asyncTask.cancel(false) and exit from doInBackground function manually checking isCancelled() value as #Pavneet advised.
I have a few fragments in my activity. Each fragment makes a call to an AsyncTask which loads data from the local DB in the onCreate() method like this:
#Override
public void onCreate(Bundle savedInstance) {
super.onCreate(savedInstance);
(new DataLoaderTask()).execute();
...
}
I have three fragments that do this. In doing so, the fragments do not finish drawing their UI until the DataLoaderTask completes. Why is this? I tried changing the call to this and I no longer have the issue:
#Override
public void onCreate(Bundle savedInstance) {
super.onCreate(savedInstance);
(new Handler()).postDelayed(new Runnable() {
#Override
public void run() {
(new DataLoaderTask()).execute();
}
}
...
}
Why does making the call inside a Runnable passed into a Handler work? Shouldn't the AsyncTask be running in the background anyway and hence the UI should get drawn before it completes?
Thanks for your help.
UPDATE: Adding more info.
Here's the constructor of DataLoaderTask():
public DataLoaderTask(Object object) {
mObject = object;
mListeners = new ArrayList<OnUpdateListener>();
}
DataLoaderTask does NOT override the onPreExecute() method. It does override the onPostExecute() method. I've timed my onPostExecute() method and it takes approx ~2ms. All it's doing is updating some objects and calling a method on any Listeners provided.
UPDATE: Here's the full onPostExecute() method:
#Override
protected void onPostExecute(Object result) {
synchronized(mDataManagerLock) {
if (Config.isLogging()) {
Log.i(TAG, "*** *** *** *** Finished syncing with database (onPostExecute()).");
}
if (mObject instanceof Playlist && result instanceof Playlist) {
if (((Playlist) result).isMyPlaylist()) {
synchronized(mTmpMyPlaylist) {
if (mTmpMyPlaylist != null && !mTmpMyPlaylist.isEmpty()) {
((Playlist) result).addPlaylistActions(mTmpMyPlaylist.getPlaylistActions());
mTmpMyPlaylist.clear();
}
}
}
if (mergeLocalPlaylistChanges((Playlist) result) && Config.isLogging()) {
Log.i(TAG, "Local playlist changes during sync merged.");
} else if (Config.isLogging()) {
Log.i(TAG, "No local playlist changes were made during sync.");
}
((Playlist) mObject).replace((Playlist) result);
putPlaylist((Playlist) mObject, null /*newClips*/);
} else if (mObject instanceof Catalog && result instanceof Catalog) {
((Catalog) mObject).replace((Catalog) result);
putCatalog((Catalog) mObject, null);
} else if (mObject instanceof NotificationsList) {
// We've synced NotificationsList in Memory with Disk.
mNotificationsList.setLastNetworkFetchTime(mApp.getNotificationsNetworkFetchTime());
} else if (mObject instanceof SetsList) {
// We've synced SetsList in Memory with Disk.
mSetsList.setLastNetworkFetchTime(mApp.getExploreNetworkFetchTime());
}
if (Config.isLogging()) {
Log.i(TAG, mObject.getClass().getSimpleName() + " after sync with database: " + mObject);
}
}
if (Config.isLogging()) {
Log.i(TAG, "Finished syncing in memory object/list with database.\n *** Time taken: " + (System.currentTimeMillis() - mStartTime)/1000 + " milliseconds.");
}
if (mListeners != null) {
for (OnUpdateListener listener : mListeners) {
if (listener != null) {
listener.onUpdated();
}
}
}
}
As you mentioned, anything resource intensive or that is going to take some time should be done in doInBackground. This includes not running anything that might hold it off in onPostExecute since we know that it runs in the main thread (with some exceptions) and might cause unexpected behavior like this.
I've ran some tests, apparently the main thread is being hold by onPostExecute.
I created a dummy Task:
class MyAsyncTask extends AsyncTask<Void, Void, Void> {
#Override
protected Void doInBackground(Void... params) {
return null;
}
#Override
protected void onPostExecute(Void result) {
try {
Log.i(TAG, "I'm holding the UI back.");
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
super.onPostExecute(result);
}
}
Even if you post to a handler it takes the task and holds it. It wasn't until I added it to a Thread that the UI was printing on time:
#Override
protected void onPostExecute(Void result) {
new Thread(new Runnable() {
#Override
public void run() {
try {
Log.i(TAG, "I'm NOT holding the UI back.");
Thread.sleep(3000);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}).start();
super.onPostExecute(result);
}
Moral of the story, DO NOT do anything that might hold the main thread. And I am not saying you should create a Thread in onPostExecute either, that is beyond a bad practice if you are not somehow managing that thread.
I am using AsyncTask in my Android application.
Here is my task:
public class MyTask extends AsyncTask<String, String, Boolean> {
private ProgressDialog progressDialog;
private boolean isCancelled = false;
public MyTask(ProgressDialog progressDialog) {
this.progressDialog = progressDialog;
}
#Override
protected Boolean doInBackground(String... params) {
try {
if (!isCancelled()) {
isCancelled = false;
} else
isCancelled = true;
} catch (Exception e) {
isCancelled = true;
}
return isCancelled;
}
#Override
protected void onCancelled() {
super.onCancelled();
isCancelled = true;
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
progressDialog.dismiss();
if (!isCancelled) {
// start an activity
}
}
}
I want to cancel this task when pressing device's back button and also cancel the ProgressDialog, but this task executes quickly. When the back button is pressed, the ProgressDialog is cancelled, but the task completes.
This AsyncTask is invoked from an activity like this:
ProgressDialog progressDialog = new ProgressDialog(this);
progressDialog.setMessage("Loading");
progressDialog.setOnCancelListener(new OnCancelListener() {
#Override
public void onCancel(DialogInterface dialog) {
if (myTask!= null
&& myTask.getStatus() != AsyncTask.Status.FINISHED
&& !myTask.isCancelled()) {
myTask.cancel(true);
}
}
});
progressDialog.show();
myTask = new MyTask(progressDialog);
myTask.execute();
When logging, I found that the dialog is dismissed (invokes onDismissListener) after executing the condition of onPostExecute(). How can I cancel this task properly?
My intention is cancel the task with back button press whether the task completes or not. Is it possible to cancel an AsyncTask from its onPostExecute()?
Actually, your code looks right,
In ProgressDialog's OnCancel()
After invoking myTask.cancel(true); method, onCancelled(Object), instead of
onPostExecute(Object) will be invoked after doInBackground(Object[]).
Note:
If you call cancel(true), an interrupt will be sent to the background thread,
which may help interruptible tasks. Otherwise, you should simply make sure to check
isCancelled() regularly in your doInBackground() method.
You can see examples of this at http://code.google.com/p/shelves.
But I suggest you to not canceling AsyncTask and just maintain your boolean Flag only dismiss the dialog on back pressed and onPostExecute() of AsyncTask decide what to do with result using your boolean flag condition.
Halo, the first i want to know the idle time at my android application. after that, i will do something if it is a idle time mode.
I follow this link.
Application idle time
my program work properly, but suddenly the problem show up. I can't move to the other page (for example to the login page) or pop up a message using alertdialog because its in a thread. Do you have any solutions?
public class ControlActivity extends Activity {
private static final String TAG=ControlActivity.class.getName();
/**
* Gets reference to global Application
* #return must always be type of ControlApplication! See AndroidManifest.xml
*/
public ControlApplication getApp()
{
return (ControlApplication )this.getApplication();
}
#Override
public void onUserInteraction()
{
super.onUserInteraction();
getApp().touch();
Log.d(TAG, "User interaction to "+this.toString());
}
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}}
here is my ControlApplication.java
public class ControlApplication extends Application {
private static final String TAG=ControlApplication.class.getName();
private Waiter waiter;
#Override
public void onCreate() {
super.onCreate();
Log.d(TAG, "Starting application"+this.toString());
//setContentView(R.layout.activity_main);
waiter=new Waiter(5*60*1000); //5 mins
waiter.start();
Toast.makeText(ControlApplication.this, "start", Toast.LENGTH_LONG).show();
}
public void touch()
{
waiter.touch();
Toast.makeText(ControlApplication.this, "touch", Toast.LENGTH_LONG).show();
} }
here is the Waiter.java
public class Waiter extends Thread implements Runnable{
private static final String TAG=Waiter.class.getName();
private long lastUsed;
private long period;
private boolean stop;
Context activity;
public Waiter(long period)
{
this.period=period;
stop=false;
}
#SuppressLint("ParserError")
public void run()
{
long idle=0;
this.touch();
do
{
idle=System.currentTimeMillis()-lastUsed;
Log.d(TAG, "Application is idle for "+idle +" ms");
try
{
Thread.sleep(5000); //check every 5 seconds
}
catch (InterruptedException e)
{
Log.d(TAG, "Waiter interrupted!");
}
if(idle > period)
{
idle=0;
//do something here - e.g. call popup or so
//Toast.makeText(activity, "Hello", Toast.LENGTH_LONG).show();
stopCounter();
}
}
while(!stop);
Log.d(TAG, "Finishing Waiter thread");
}
public synchronized void touch()
{
lastUsed=System.currentTimeMillis();
}
public synchronized void forceInterrupt()
{
this.interrupt();
}
//soft stopping of thread
public synchronized void stopCounter()
{
stop=true;
}
public synchronized void setPeriod(long period)
{
this.period=period;
}}
I tried to create a new class and call a method to intent. Its also fail. tried to pop up a message from that method its also fail.
do you guys have any other solutions for idle time? thanks.
Regards,
Alfred Angkasa
In you active activity, instead of this thread, do:
public class Graph extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
while(idle = 0) {
idle = System.currentTimeMillis()-lastUsed;
if(idle != period) {
Intent goNextActivity = new Intent(com.package.theactivity);
else {
idle == 0;
}
}
}
}
I just found by myself the answer by search on google and try for 5 hours.. :D
I hope my answer will help you too.
First, I mix the ControlApplication and Waiter with ControlActivity. Thats mean I don't need both files. My ControlActivity will extends the activity (its use for me to intent to the other page if in idle mode), and i will implements runnable(its use for me to run the thread).
after that i have a method called onUserInteraction(), this method help me to get the user interaction, whenever the user touch or click something.
in the onCreate, i initiate all the variable including lastUsed, period, and stop.
why should I initiate that? because you need to know how many seconds to know that your apps is on idle mode or not. that was period use. Stop variable is use for me to iterate and searching every 5 seconds(you can also make it every second to check idle or not) my apps is idle or not. I initiate lastUsed by calling method touch. I copied touch method from ControlApplication into my ControlActivity. By calling touch method, I can know when is my lastused. After that I start my thread.
in my run method, i set idle = 0. and do some looping to check. i check every 5 seconds to know my apps is on idle mode or not.
idle = System.System.currentTimeMillis()-lastUsed -> i used this to know if the idle is already suite with the period or not using if method.
if the idle is greater than period, my apps must be in idle mode. after that i stop the iteration and using handler to manage it.
i set handler.sendEmptyMessage(0), and create Handler. At handler i move to the other page.
this is my full code.
public class MainActivity extends Activity implements Runnable {
private static final String TAG= MainActivity.class.getName();
private long lastUsed;
private int period;
private boolean stop;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
period = 10000;
stop=false;
touch();
Thread currentThread = new Thread(this);
currentThread.start();
Toast.makeText(getApplicationContext(), "Start", Toast.LENGTH_SHORT).show();
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.activity_main, menu);
return true;
}
#Override
public void onUserInteraction()
{
super.onUserInteraction();
touch();
Log.d(TAG, "User interaction to "+this.toString());
}
public synchronized void touch()
{
lastUsed=System.currentTimeMillis();
Toast.makeText(getApplicationContext(), "touch", Toast.LENGTH_SHORT).show();
}
public void moveIntent() {
Intent intent = new Intent(this, AfterIdle.class);
startActivity(intent);
}
public void validate(View view) {
switch (view.getId()) {
case R.id.button1 :
Intent intent = new Intent(this, AfterIdle.class);
startActivity(intent);
break;
}
}
#Override
public void run() {
// TODO Auto-generated method stub
long idle;
while (!stop) {
idle=System.currentTimeMillis()-lastUsed;
try
{
Thread.sleep(5000); //check every 5 seconds
}
catch (InterruptedException e)
{
Log.d(TAG, "Waiter interrupted!");
}
if (idle > period) {
idle = 0;
stop = true;
}
}
handler.sendEmptyMessage(0);
}
public Handler handler = new Handler() {
#Override
public void handleMessage(Message msg) {
moveIntent();
}
};}
I hope this code will help another people if they have the same problem that i faced last time. I wish someone would correct the answer for me if my answer is wrong.
thanks.
Regards,
Alfred Angkasa