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

如果愿意，可以将创建者实例放入循环中，并从数组中动态添加名称。

-(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
}

objective - c

// Create the Button with RoundedRect type
UIButton *mybutton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
// instend of "Click Me" you can write your own message/Label
[mybutton setTitle:@"Click Me" forState:UIControlStateNormal];
// create the Rectangle Frame with specified size
mybutton.frame = CGRectMake(10, 10, 300, 140); // x,y,width,height    [self.view addSubview:mybutton];// add button to your view.

斯威夫特

let button   = UIButton(type: UIButtonType.System) as UIButton
button.frame = CGRectMake(100, 100, 100, 50)
button.backgroundColor = UIColor.greenColor()
button.setTitle("Test Button", forState: UIControlState.Normal)
self.view.addSubview(button)

这是一个创建三个按钮的例子。只是移动他们的位置。

UIImage *buttonOff = [UIImage imageNamed:@"crysBallNorm.png"];
UIImage *buttonOn = [UIImage imageNamed:@"crysBallHigh.png"];

UIButton *predictButton = [UIButton alloc];
predictButton = [UIButton buttonWithType:UIButtonTypeCustom];
predictButton.frame = CGRectMake(180.0, 510.0, 120.0, 30.0);
[predictButton setBackgroundImage:buttonOff forState:UIControlStateNormal];
[predictButton setBackgroundImage:buttonOn forState:UIControlStateHighlighted];
[predictButton setTitle:@"Predict" forState:UIControlStateNormal];
[predictButton setTitleColor:[UIColor purpleColor] forState:UIControlStateNormal];
[predictButton addTarget:self action:@selector(buttonPressed:) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:predictButton];

在Swift 5和Xcode 10.2中

基本上我们有两种类型的按钮。

1)系统类型按钮

2)自定义类型按钮(在自定义类型按钮中，我们可以为按钮设置背景图像)

而且这两种类型的按钮控制状态很少https://developer.apple.com/documentation/uikit/uicontrol/state

重要的州有

1)正常状态

2)选定状态

3)高亮状态

4)禁用状态……

//For system type button
let button = UIButton(type: .system)
button.frame = CGRect(x: 100, y: 250, width: 100, height: 50)
//  button.backgroundColor = .blue
button.setTitle("Button", for: .normal)
button.setTitleColor(.white, for: .normal)
button.titleLabel?.font = UIFont.boldSystemFont(ofSize: 13.0)
button.titleLabel?.textAlignment = .center//Text alighment center
button.titleLabel?.numberOfLines = 0//To display multiple lines in UIButton
button.titleLabel?.lineBreakMode = .byWordWrapping//By word wrapping
button.tag = 1//To assign tag value
button.btnProperties()//Call UIButton properties from extension function
button.addTarget(self, action:#selector(self.buttonClicked), for: .touchUpInside)
self.view.addSubview(button)

//For custom type button (add image to your button)
let button2 = UIButton(type: .custom)
button2.frame = CGRect(x: 100, y: 400, width: 100, height: 50)
//        button2.backgroundColor = .blue
button2.setImage(UIImage.init(named: "img.png"), for: .normal)
button2.tag = 2
button2.btnProperties()//Call UIButton properties from extension function
button2.addTarget(self, action:#selector(self.buttonClicked), for: .touchUpInside)
self.view.addSubview(button2)

@objc func buttonClicked(sender:UIButton) {
    print("Button \(sender.tag) clicked")
}

//You can add UIButton properties using extension
extension UIButton {
    func btnProperties() {
        layer.cornerRadius = 10//Set button corner radious
        clipsToBounds = true
        backgroundColor = .blue//Set background colour
        //titleLabel?.textAlignment = .center//add properties like this
    }
}