从Swift 3开始，语法有了一些变化。

以下是如何创建Swift 3的基本按钮:

    let button = UIButton(type: UIButtonType.system) as UIButton
    button.frame = CGRect(x: 100, y: 100, width: 100, height: 50)
    button.backgroundColor = UIColor.green
    button.setTitle("Example Button", for: UIControlState.normal)
    self.view.addSubview(button)

以下是Swift自以前版本以来所做的更改:

let button = UIButton(type: UIButtonType.System) as UIButton

// system no longer capitalised

button.frame = CGRectMake(100, 100, 100, 50)

// CGRectMake has been removed as of Swift 3

button.backgroundColor = UIColor.greenColor()

// greenColor replaced with green

button.setTitle("Example Button", forState: UIControlState.Normal)

// normal is no longer capitalised

self.view.addSubview(button)

-(void)addStuffToView
{
    UIButton *aButton = [[UIButton alloc] initWithFrame:CGRectMake(20, 20, 20, 20)]; //(x, y, width, height of button on screen
    [aButton setTitle:@"Button" forState:UIControlStateNormal];//puts the text on the button
    aButton.titleLabel.font = somefont;//sets the font if one is already stated
    aButton.titleLabel.font = [UIFont fontWithName:@"Arial-MT" size:12];//sets the font type and size
    [aButton addTarget:self action:@selector(back) forControlEvents:UIControlEventTouchUpInside];//see back method below
    [aButton setBackgroundImage:[UIImage imageNamed:@"someImage.png"] forState:UIControlStateNormal];//sets the image of the button
    [self.view addSubview:back];
}

-(void)back
{
    UIAlertView *alert = [[UIAlertView alloc]initWithTitle.....]
}

-(void)viewDidLoad
{
    [super viewDidLoad];
    [self addStuffToView];//adds all items built in this method to the view
}

- (void)viewDidLoad {
    [super viewDidLoad];
    [self addMyButton];   // Call add button method on view load
}

- (void)addMyButton{    // Method for creating button, with background image and other properties

    UIButton *playButton = [[UIButton buttonWithType:UIButtonTypeRoundedRect] retain];
    playButton.frame = CGRectMake(110.0, 360.0, 100.0, 30.0);
    [playButton setTitle:@"Play" forState:UIControlStateNormal];
    playButton.backgroundColor = [UIColor clearColor];
    [playButton setTitleColor:[UIColor whiteColor] forState:UIControlStateNormal ];
    UIImage *buttonImageNormal = [UIImage imageNamed:@"blueButton.png"];
    UIImage *strechableButtonImageNormal = [buttonImageNormal stretchableImageWithLeftCapWidth:12 topCapHeight:0];
    [playButton setBackgroundImage:strechableButtonImageNormal forState:UIControlStateNormal];
    UIImage *buttonImagePressed = [UIImage imageNamed:@"whiteButton.png"];
    UIImage *strechableButtonImagePressed = [buttonImagePressed stretchableImageWithLeftCapWidth:12 topCapHeight:0];
    [playButton setBackgroundImage:strechableButtonImagePressed forState:UIControlStateHighlighted];
    [playButton addTarget:self action:@selector(playAction:) forControlEvents:UIControlEventTouchUpInside];
    [self.view addSubview:playButton];  
}

UIButton *custombutton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
[custombutton addTarget:self
                 action:@selector(aMethod:)
       forControlEvents:UIControlEventTouchUpInside];
[custombutton setTitle:@"Click" forState:UIControlStateNormal];
custombutton.frame = CGRectMake(80.0, 110.0, 160.0, 40.0);
custombutton.titleLabel.textColor = [UIColor colorWithRed: 2.0f/255.0f green: 155.0f/255.0f blue: 213.0f/255.0f  alpha:1];
 [custombutton setImage:[UIImage imageNamed:@"hh.png"] forState:UIControlStateNormal];
 [view addSubview:custombutton];

拜托，都2014年了!为什么代码块评估分配还没有被使用，因为趋势表明这是未来的趋势!

UIButton* button = ({
    //initialize button with frame
    UIButton* button = [[UIButton alloc] initWithFrame:({
        CGRect frame = CGRectMake(10.0, 10.0, 200.0, 75.0);
        frame;
    })];
    //set button background color
    [button setBackgroundColor:({
        UIColor* color = [UIColor colorWithRed:1.0 green:1.0 blue:0.0 alpha:1.0];
        color;
    })];
    //set button title for state
    [button setTitle:({
        NSString* string = [NSString stringWithFormat:@"title words"];
        string;
    }) forState:({
        UIControlState state = UIControlStateNormal;
        state;
    })];
    //set selector
    [button addTarget:self action:({
        SEL select = @selector(method:);
        select;
    }) forControlEvents:({
        UIControlEvents event = UIControlEventTouchUpInside;
        event;
    })];
    //return button
    button;
});
[self.view addSubview:button];

哇!

或者确切的结果可以这样完成:

UIButton* button = [[UIButton alloc] initWithFrame:CGRectMake(10.0, 10.0, 200.0, 75.0)];
[button setBackgroundColor:[UIColor colorWithRed:1.0 green:1.0 blue:0.0 alpha:1.0]];
[button setTitle:@"title words" forState:UIControlStateNormal];
[button addTarget:self action:@selector(method:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:button];

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