java - Display ProgressBar while saving an image from Activity -

in app letting user save drawing. while drawing saved, want display progress bar on top of drawing let user know saving.

my xml layout:

<framelayout     android:id="@+id/viewd"     android:layout_width="match_parent"     android:layout_height="0dp"     android:layout_weight="3"     android:orientation="vertical"     android:layout_gravity="center" >     <linearlayout         android:orientation="horizontal"         android:layout_width="fill_parent"         android:layout_height="fill_parent"         android:padding="0dp"         android:background="@drawable/bd"         android:id="@+id/llfreedraw" >     </linearlayout>     <progressbar          android:layout_height="fill_parent"         android:layout_width="fill_parent"         style="@android:style/widget.progressbar.large"         android:id="@+id/pbsave"         android:visibility="invisible" /> </framelayout> 

portion of java code is:

view.onclicklistener savehandle = new view.onclicklistener() {     public void onclick(view v) {         savepb = (progressbar) findviewbyid(r.id.pbsave);         savepb.setvisibility(view.visible);         view content = layout;         content.setdrawingcacheenabled(true);         content.setdrawingcachequality(view.drawing_cache_quality_high);         bitmap bitmap = content.getdrawingcache();         file folder = new file(environment.getexternalstoragedirectory() + "/pb");         if (!folder.exists()) {             folder.mkdir();         }         file = new file(folder + "/pb_image_" + math.random()  + ".png");         fileoutputstream ostream;         try {             file.createnewfile();             ostream = new fileoutputstream(file);             bitmap.compress(compressformat.png, 100, ostream);             ostream.flush();             ostream.close();             displaytoast("image saved.");             savepb.setvisibility(view.gone);             btnsave.setvisibility(view.gone);             btnshare.setvisibility(view.visible);         } catch (exception e) {             e.printstacktrace();             displaytoast("unable save image. try again later.");         }     } }; 

i want display progress bar on top of framelayou, 25% transparent background. image saving not see progress bar. idea how modify works way wanting to?

asynctask can handle this.

public class saveimagetask extends asynctask<void, void, void> {      @override      protected void doinbackground(void... params) {          // save image here.          return null;      }       @override      protected void onpreexecute(){          // show progress bar here.      }       @override      protected void onpostexecute() {          // hide progress bar here.            }  } 

call like:

new saveimagetask().execute(null, null, null);