swift - Using Selectors as variables with addTarget -



swift - Using Selectors as variables with addTarget -

i having problems selectors in swift. have next lines of code:

let actiontarget="onpress:" button.addtarget(self, action: selector(actiontarget), forcontrolevents: .touchupinside)

but generates error:

! not find fellow member 'touchupinside'

however error disappears if try:

button.addtarget(self, action "onpress:", forcontrolevents: .touchupinside)

so assuming not .touchupinside causing me problems, lack of string literal causing me problems.

i have tried:

let actiontarget="onpress:" selector button.addtarget(self, action: actiontarget, forcontrolevents: .touchupinside)

but didnt work either.

how can supply action selector not string literal, instead stored in variable?

button.addtarget(self, action: "onpress:", forcontrolevents: .touchupinside)

this one's right -- don't need special selector() utilize selector, using string do.

if selector stored in variable, utilize this:

let selector = "onpress:" button.addtarget(self, action: selector(selector), forcontrolevents: .touchupinside)

the reason as isn't right here because it's used cast superclass subclass. example, let p:uiview = uibutton(...) , p uibutton work since p in fact uibutton instance. in case, using selector( ... ) calls appropriate selector constructor , instantiates new selector string.

swift

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