ios - UIView animation happening immediately -

i have animation of 3 buttons used work until added different possible positions buttons. animation happens immediately, i'm not sure why.

here's code:

defaults=[nsuserdefaults standarduserdefaults]; _btncuenta3.hidden=no; cgpoint newposition2; cgpoint newposition3; cgpoint newpositionagregar; if([defaults objectforkey:@"cuenta3"]){     newposition2=cgpointmake(200.0f + _btncuenta2.frame.size.width/2.0f, _btncuenta2.center.y);     newposition3=cgpointmake(165.0f + _btncuenta3.frame.size.width/2.0f, _btncuenta3.center.y);     newpositionagregar=cgpointmake(130.0f + _btnagregar.frame.size.width/2.0f, _btnagregar.center.y);     _btncuenta2.center=newposition2;     _btncuenta3.center=newposition3;     _btnagregar.center=newpositionagregar; }else if([defaults objectforkey:@"cuenta2"]){     newposition2=cgpointmake(200.0f + _btncuenta2.frame.size.width/2.0f, _btncuenta2.center.y);     newpositionagregar=cgpointmake(165.0f + _btnagregar.frame.size.width/2.0f, _btnagregar.center.y);     _btncuenta2.center=newposition2;     _btnagregar.center=newpositionagregar; }else{     newpositionagregar=cgpointmake(200.0f + _btnagregar.frame.size.width/2.0f, _btnagregar.center.y);     _btnagregar.center=newpositionagregar; } [uiview beginanimations:nil context:nil]; [uiview setanimationduration:1.0f]; [uiview commitanimations]; 

any idea why it's happening or how can fix it?

i think [uiview beginanimations:nil context:nil]; should first line before doing changes uiview contents.

code:

[uiview beginanimations:nil context:nil]; [uiview setanimationduration:1.0f];  //view changes code  [uiview commitanimations];