ios - UILabel change height, animation expands from center -

i'm trying increase labels height using animation, animation causes label first expand center, , jump in place correct y point. looks terrible. bottom expand.

[uiview animatewithduration:0.5 delay:0.0f options:uiviewanimationoptiontransitionnone animations:^{     [self.about increaseheightfromtopleft:deltaheight];     [self.scrollview increasecontentheight];  } completion:nil];   - (void)increaseheightfromtopleft:(cgfloat ) increased  {      cgrect newframe = cgrectmake(self.originx, self.originy, self.framewidth, self.frameheight + increased);      self.frame = newframe; } 

the label called about, can see video of animation here. https://www.youtube.com/watch?v=dcqktiz9moy&feature=youtu.be

faced same problem! try set label' contentmode top in code:

label.contentmode = uiviewcontentmodetop;