android - Floating Action Button from support library custom animation (pre lollipop) -

i add rotate animation simulate circular progress bar time consuming operations started fab. working nicely on lollipop, animation not start on kitkat. glue? thanks.

• compilesdkversion 23
• buildtoolsversion '23.0.2'
• minsdkversion 16
• compile 'com.android.support:design:23.1.1
• compile 'com.android.support:support-v4:23.1.1'

layout.xml

<android.support.design.widget.floatingactionbutton     android:id="@+id/review_button"     android:layout_width="wrap_content"     android:layout_height="wrap_content"     android:layout_alignparentbottom="true"     android:layout_alignparentright="true"     android:layout_gravity="center"     android:layout_margin="@dimen/fab_margin_right"     android:src="@drawable/ic_send_white_24dp"     android:visibility="invisible"     app:elevation="@dimen/elevation_high"     tools:visibility="visible"     />   

myfragment.java

       @override     public view oncreateview(layoutinflater inflater, viewgroup container, bundle savedinstancestate) {         view view = inflater.inflate(r.layout.layout, container, false);         button = (floatingactionbutton) view.findviewbyid(r.id.review_button);         button.setonclicklistener(new view.onclicklistener() {             public void onclick(view v) {                 startlongoperation();                 dolongoperation();             }         });         // delayed show button animation start         button.postdelayed(new runnable() {             @override             public void run() {                 button.show();             }         }, 250);         return view;     }      /** disable form , show progress */     protected void startlongoperation() {         button.setclickable(false);         button.setbackgroundtintlist(colorstatelist.valueof(color.ltgray));         button.startanimation(animationutils.loadanimation(getactivity(), r.anim.rotate));         text.setenabled(false);         ...     }      /** enable form , stop progress */     protected void stoplongoperation() {         if (null != getactivity()) {             button.setclickable(true);             button.setbackgroundtintlist(colorstatelist.valueof(getresources().getcolor(r.color.zelena)));             button.clearanimation();             text.setenabled(true);             ...         }     }     }      public void dolongoperation() {          ...          // call stop animation when finished          stoplongoperation();     }