UIButton *buttonName = [UIButton
buttonWithType:UIButtonTypeRoundedRect];
[buttonName addTarget:self 
    action:@selector(aMethod:)forControlEvents:UIControlEventTouchDown];
[buttonName setTitle:@"Show View" forState:UIControlStateNormal];
.frame = CGRectMake(80.0, 210.0, 160.0, 40.0); [view
addSubview:buttonName];

UIButton *addProject = [UIButton buttonWithType: UIButtonTypeRoundedRect];
addProject.frame = CGRectMake(210, 285, 100, 18);
[addProject setTitle:@"Show View" forState:UIControlStateNormal];
[addProject addTarget:self action:@selector(addProjectPressed:) forControlEvents:UIControlEventTouchUpInside];
[_scrollView addSubview:addProject];

Swift 3版本应该是:

let myButton:UIButton = {
    let myButton = UIButton() // If you want to set the type use like
                              // UIButton(type: .RoundedRect) or
                              // UIButton(type: .Custom)
    myButton.setTitle("Hai Touch Me", for: .normal)
    myButton.setTitleColor(UIColor.blue, for: .normal)
    myButton.frame = CGRect(x: 20, y: 20, width: 100, height: 40)

    myButton.addTarget(self, action: #selector(ViewController.pressedAction(_:)), for: .touchUpInside)
    self.view.addSubview(myButton)

    return myButton
}()

UIButton *buttonName = [UIButton
buttonWithType:UIButtonTypeRoundedRect];
[buttonName addTarget:self 
    action:@selector(aMethod:)forControlEvents:UIControlEventTouchDown];
[buttonName setTitle:@"Show View" forState:UIControlStateNormal];
.frame = CGRectMake(80.0, 210.0, 160.0, 40.0); [view
addSubview:buttonName];

为了以编程方式创建UIButton，我们可以在objective - c和swift中创建

斯威夫特3

let buttonSwift   = UIButton(type: UIButtonType.system) as UIButton
                      //OR 
let buttonSwift   = UIButton(type: UIButtonType.Custom) as UIButton
//Set Frame for Button
buttonSwift.frame = CGRect(x: 100, y: 100, width: 200, height: 100)
//Set title for button
buttonSwift.setTitle("ClickMe", for: .normal)
//If you want to set color for button title
buttonSwift.setTitleColor(UIColor.white, for: .normal)
//If you want to set Background color for button
buttonSwift.backgroundColor = UIColor.black
//If you want to set tag for button
buttonSwift.tag = 0
//If you want to add or set image for button
let image = UIImage(named: "YourImageName") as UIImage?
buttonSwift.setImage(image, for: .normal)
//If you want to add or set Background image for button
buttonSwift.setBackgroundImage(image, for: .normal)
//Add action for button
buttonSwift.addTarget(self, action: #selector(actionPressMe), for:.touchUpInside)
//Add button as SubView to Super View
self.view.addSubview(buttonSwift)

UIButton动作方法

func actionPressMe(sender: UIButton!) 
{
    NSLog("Clicked button tag is %@", sender.tag)
               OR
    print("Clicked button tag is \(sender.tag)")

    //Then do whatever you want to do here

    ........  
}

OBJECTIVE - C

UIButton *buttonObjectiveC = [UIButton buttonWithType:UIButtonTypeCustom];
           OR
UIButton *buttonObjectiveC = [UIButton buttonWithType:UIButtonTypeSystem];
buttonObjectiveC.frame = CGRectMake(200, 100, 200, 100);
//Set title for button
[buttonObjectiveC setTitle:@"ClickMe" forState:UIControlStateNormal];
//If you want to set color for button title
[buttonObjectiveC setTitleColor:[UIColor  whiteColor] forState: UIControlStateNormal];
//If you want to set Background color for button
[buttonObjectiveC setBackgroundColor:[UIColor blackColor]];
//If you want to set tag for button
buttonSwift.tag = 0;
//If you want to add or set image for button
UIImage *image = [UIImage imageNamed:@"YourImageName"];
[buttonObjectiveC setImage:image forState:UIControlStateNormal];
//If you want to add or set Background image for button
[buttonObjectiveC setBackgroundImage:image forState:UIControlStateNormal];
//Add action for button
[buttonObjectiveC addTarget:self action:@selector(actionPressMe:)forControlEvents:UIControlEventTouchUpInside];
//Add button as SubView to Super View
[self.view addSubview:buttonObjectiveC];

UIButton动作方法

- (void)actionPressMe:(UIButton *)sender 
{
    NSLog(@"Clicked button tag is %@",sender.tag);
    //Then do whatever you want to do here
    ..........
}

输出截图为

这里有一个:

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
[button addTarget:self 
           action:@selector(aMethod:)
 forControlEvents:UIControlEventTouchUpInside];
[button setTitle:@"Show View" forState:UIControlStateNormal];
button.frame = CGRectMake(80.0, 210.0, 160.0, 40.0);
[view addSubview:button];