I have a question about UIView
, what's the difference between views hidden, alpha and opaque?
The effect of setting view: hidden = yes and view.alpha = 0.0f is the same.
I have a question about UIView
, what's the difference between views hidden, alpha and opaque?
The effect of setting view: hidden = yes and view.alpha = 0.0f is the same.
setting view.hidden = yes
will hide the view andview.alpha = 0.0f
will set the colors of view alpha 0.0 which will make the view invisible, so both are not same.... :)The differences are subtle. According to the UIView class reference:
opaque
tells the system that the view has no transparency and is thus faster to render because calculations for blending can be skippedhidden
is boolean property that changes only the visibility of the current view and hides it from ui events.alpha
is an animatable propertySetting
alpha = 0.0f
orhidden = YES
has the same visual effect. However usinghidden
to actually hide a view not only in a graphical sense but also from ui events might result in a more efficient responder chain when you have lots of nested views.