Hi,
You have to put the while(isStop) loop in your Thread's run() method,
not inside the new Runnable that you post:
public MyThread extends Thread {
Handler handler;
public MyThread() {
super();
handler = new Handler();
}
public void run() {
..
while(isStop){
...
handler.post(new Runnable() {
public void run() {
imgData = getImage(); // imgData receive jpeg image data
bm = BitmapFactory.decodeByteArray(imgData,
0,imgData.length); //
convert jpeg image into bitmap
imgView.setBitmap(bm);
}
});
...
}
...
}
}
Anything that you need to run using the 'handler.post()' method must
run in a very short time, otherwise your user-input handling will not
work and your app will lock up. In your example, the while(isStop)
would not stop looping, causing the posted runnable to run almost
forever --> locking up your app.
You have to code your 'MyThread' class to accept jobs/requests from
your main UI-thread. Your thread will handle these requests and then
call the handler.post() method to show the results in form of a
different bitmap.
To do this can be a bit daunting if you don't have much Threading
experience. I suggest you taking a good look at the
java.util.concurrent.ExecutorService classes and the FutureTask
classes. These classes do a lot of that hard work already for you.
//Code in your main-thread:
ExecutorService executor = Executors.newSingleThreadExecutor();
...
...
// when you need to update the bitmap in the imgView:
FutureTaks<?> task = executor.submit(new Runnable() {
public void run() {
... // do the work to figure out the bitmap
imgData = getImage(); // imgData receive jpeg image data
bm = BitmapFactory.decodeByteArray(imgData,0,imgData.length); //
get bitmap
// post back to the main thread with the new bitmap.
post(new Runnable() {
public void run() {
imgView.setBitmap(bm);
}
});
}
});
Now 'task' holds the task being executed in a seperate thread by the
ExecutorService you created.
You can actually call 'cancel' on 'task' to cancel submitted jobs/
requests/etc. It's all done for you :)
On Mar 3, 2:00 am, 민승기 <[email protected]> wrote:
> Thank you for your answer !
>
> imgView.setBitmap(bm) is working very well without failure in thred routine
> as you described
>
> but I need refreshing of screen with new bitmap image data repeatedly.
>
> In addition to your code, for the purpose of refreshing new image data, I
> added infinite loop with while(isStop) operation.
>
> public MyThread extends Thread {
> Handler handler;
> public MyThread() {
> super();
> handler = new Handler();
> }
> public void run() {
> ..
> ...
> handler.post(new Runnable() {
> public void run() {
> while(isStop){
> imgData = getImage(); // imgData receive jpeg image data
> bm = BitmapFactory.decodeByteArray(imgData,0,imgData.length); //
> convert jpeg image into bitmap
> imgView.setBitmap(bm);
> }
> }
> });
> ...
> }
>
> }
>
> then this program works with no error.
> While loop goes on...
> I can have right image data, but display never refresh with new image data.
> and program didn't response any kind of input such like a button.
>
> 2009/3/3 Streets Of Boston <[email protected]>
>
>
>
>
>
> > imgView.setBitmap can not be called from any other thread than the
> > main thread (i.e. thread on which you created your view).
>
> > do this instead:
>
> > handler.post(new Runnable() {
> > public void run() {
> > imgView.setBitmap(bm);
> > }
> > });
>
> > The 'handler' can be created by just calling 'new Handler()' on the
> > main thread, e.g. when you create your worker-thread.
>
> > public MyThread extends Thread {
> > Handler handler;
> > public MyThread() {
> > super();
> > handler = new Handler();
> > }
> > public void run() {
> > ..
> > ...
> > handler.post(new Runnable() {
> > public void run() {
> > imgView.setBitmap(bm);
> > }
> > });
> > ...
> > }
> > }
> > On Mar 2, 4:47 am, rex <[email protected]> wrote:
> > > Hi~
>
> > > I'm trying to periodically change image data in ImageView in the
> > > thread routine
> > > but when I put this code in the tread routine, program is killed.
>
> > > imgView.setBitmap(bm);
>
> > > here is my thread code
> > > ...
>
> > > private byte[] imgData;
> > > private Bitmap bm;
>
> > > new Thread (new Runnable()
> > > {
> > > public void run()
> > > {
> > > while(!isStop){
> > > imgData = getImage();
> > > bm = BitmapFactory.decodeByteArray(imgData,
> > > 0,imgData.length);
> > > imgView.setBitmap(bm); --> This caused error!!
> > > }
> > > }
>
> > > }).start();
>
> > > ...
>
> > > imgData is receiving jpeg image data from somewhere.
> > > Outside thread routine, image data is displayed well.
>
> > > If above is impossible, are there any other ways to periodically image
> > > data refreshing on screen ?
>
> > > Thanks!- Hide quoted text -
>
> - Show quoted text -
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