如何在某些情况下更改以编程方式创建的UIButton的标题和操作

Question

I have created a UIButton programmatically on my ViewController. I want to perform different actions on the same button depending on the condition and want to change the title as well.

First I create the button like this:

func createButton(buttonTitle: String,buttonAction: Selector) -> UIButton{
    let button   = UIButton(type: UIButtonType.System) as UIButton
    button.frame = CGRectMake(0, 0, 414, 65)

    button.setTitle(buttonTitle, forState: UIControlState.Normal)
    button.addTarget(self, action:buttonAction, forControlEvents: UIControlEvents.TouchUpInside)
    button.setTitleColor(UIColor.whiteColor(), forState:UIControlState.Normal)
    button.titleLabel?.font = UIFont(name: Variables.MONTESERRAT_REGULAR, size: 20.0)

    button.backgroundColor = UIColor().blueColor()       //top
    button.titleEdgeInsets = UIEdgeInsetsMake(0.0,10.0, 10.0, 0.0)
      return button
}

Then I am showing like this

override func tableView(tableView: UITableView, viewForFooterInSection section: Int) -> UIView? {
    let footerView = UIView(frame: CGRectMake(0, 0, tableView.frame.size.width, tableView.frame.size.height))

    if(active == true){
       bottomButton = createButton("UNPUBLISH", buttonAction: "unPublishToServer")
    }else if(active == false){
        bottomButton = createButton("PUBLISH", buttonAction: "publishToServer")
    }else{
        bottomButton = createButton("Request", buttonAction: "requestItem")
    }

    footerView.addSubview(bottomButton!)
    return footerView
}

then on certain messages from server or conditions I am changing the button like this

func publishTripToServer(){
    dispatch_async(dispatch_get_main_queue()) {
        self.bottomButton?.setTitle("UNPUBLISH", forState: UIControlState.Normal)
    }
}

func unPublishTripToServer(){
    dispatch_async(dispatch_get_main_queue()) {
        self.bottomButton?.setTitle("PUBLISH", forState: UIControlState.Normal)
    }
}

The problem I am having is first it shows some background color behind the title when I click publish or unpublish. the second issue is button is not changing the action.

Answer 1

I'm not exactly sure what you mean for the background color issue.

But for your button, does something like this not work?

func publishTripToServer(){

    self.bottomButton = createButton("UNPUBLISH", buttonAction: "unPublishToServer")
}



 func unPublishTripToServer(){
     self.bottomButton = createButton("PUBLISH", buttonAction: "publishToServer")
}

I don't know why you previously were trying to update the button title on the background thread, but you shouldn't ever update ui elements asynchronously.

And the reason your button action wasn't changing is that you never told it to change - you just changed the title