How to Create a Big, Red Uibutton with iOS

How can I create a big, red UIButton with iOS?

You first start with a stretchable image:

alt text http://grab.by/4lP

Then you make a button with the stretched image as the background and apply text.

UIButton *sampleButton = [UIButton buttonWithType:UIButtonTypeCustom];
[sampleButton setFrame:CGRectMake(kLeftMargin, 10, self.view.bounds.size.width - kLeftMargin - kRightMargin, 52)];
[sampleButton setTitle:@"Button Title" forState:UIControlStateNormal];
[sampleButton setFont:[UIFont boldSystemFontOfSize:20]];
[sampleButton setBackgroundImage:[[UIImage imageNamed:@"redButton.png"] stretchableImageWithLeftCapWidth:10.0 topCapHeight:0.0] forState:UIControlStateNormal];
[sampleButton addTarget:self action:@selector(buttonPressed) forControlEvents:UIControlEventTouchUpInside];
[self.view addSubview:sampleButton];

Obviously, you will need to adjust the frame origin and size to match your app, as well as the target, selector, and title.

How can I make a button have a rounded border in Swift?

Use button.layer.cornerRadius, button.layer.borderColor and button.layer.borderWidth.
Note that borderColor requires a CGColor, so you could say (Swift 3/4):

button.backgroundColor = .clear
button.layer.cornerRadius = 5
button.layer.borderWidth = 1
button.layer.borderColor = UIColor.black.cgColor

Color Tint UIButton Image

As of iOS 7, there is a new method on UIImage to specify the rendering mode. Using the rendering mode UIImageRenderingModeAlwaysTemplate will allow the image color to be controlled by the button's tint color.

Objective-C

UIButton *button = [UIButton buttonWithType:UIButtonTypeCustom];
UIImage *image = [[UIImage imageNamed:@"image_name"] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
[button setImage:image forState:UIControlStateNormal]; 
button.tintColor = [UIColor redColor];

Swift

let button = UIButton(type: .custom)
let image = UIImage(named: "image_name")?.withRenderingMode(.alwaysTemplate)
button.setImage(image, for: .normal)
button.tintColor = UIColor.red

Make a UIButton programmatically in Swift

You're just missing the colon at the end of the selector name. Since pressed takes a parameter the colon must be there. Also your pressed function shouldn't be nested inside viewDidLoad.

override func viewDidLoad() {
    super.viewDidLoad()
    // Do any additional setup after loading the view, typically from a nib.
    let myFirstLabel = UILabel()
    let myFirstButton = UIButton()
    myFirstLabel.text = "I made a label on the screen #toogood4you"
    myFirstLabel.font = UIFont(name: "MarkerFelt-Thin", size: 45)
    myFirstLabel.textColor = .red
    myFirstLabel.textAlignment = .center
    myFirstLabel.numberOfLines = 5
    myFirstLabel.frame = CGRect(x: 15, y: 54, width: 300, height: 500)
    myFirstButton.setTitle("✸", for: .normal)
    myFirstButton.setTitleColor(.blue, for: .normal)
    myFirstButton.frame = CGRect(x: 15, y: -50, width: 300, height: 500)
    myFirstButton.addTarget(self, action: #selector(pressed), for: .touchUpInside)
}

@objc func pressed() {
    var alertView = UIAlertView()
    alertView.addButtonWithTitle("Ok")
    alertView.title = "title"
    alertView.message = "message"
    alertView.show()
}

EDIT: Updated to reflect best practices in Swift 2.2. #selector() should be used rather than a literal string which is deprecated.

If I add a background color to a UIButton, how do I inset it so the background is smaller?

One way to do this, is to set the color of a sublayer of the button rather than the background color of the button itself.

- (void)viewDidLoad {
    [super viewDidLoad];
    CALayer *sub = [CALayer new];
    sub.frame = CGRectInset(self.topButton.bounds, 5, 2.5); // this will make the layer 90x25 for a button that is 100x30
    sub.backgroundColor = [UIColor redColor].CGColor;
    [self.topButton.layer addSublayer:sub];
}

UIBezierPath rounded corners in UIButton

For using these rounded rect methods you must ensure that the view size is larger then the radius used. In your case both width and height must be larger then 40 (Radii size is 20x20 so max(20*2, 20*2) = 40).

In general I prefer having a custom method to generate such paths. Using lines and arcs usually give you better flexibility. You may try the following:

    /// Returns a path with rounded corners
    ///
    /// - Parameters:
    ///   - frame: A frame at which the path is drawn. To fit in view "bounds" should be used
    ///   - maximumRadius: A maximum corner radius used. For smaller views radius will be min(width/2, height/2)
    /// - Returns: Returns a new path
    func roundedRectPath(inRect frame: CGRect, radiusConstrainedTo maximumRadius: CGFloat) -> UIBezierPath {

        let radisu = min(maximumRadius, min(frame.size.width*0.5, frame.size.height*0.5))

        let path = UIBezierPath()

        path.move(to: CGPoint(x: frame.origin.x + radisu, y: frame.origin.y)) // Top left
        path.addLine(to: CGPoint(x: frame.origin.x + frame.size.width - radisu, y: frame.origin.y))  // Top right
        path.addQuadCurve(to: CGPoint(x: frame.origin.x + frame.size.width, y: frame.origin.y + frame.size.height - radisu), controlPoint: CGPoint(x: frame.origin.x + frame.size.width, y: frame.origin.y)) // Top right arc
        path.addLine(to: CGPoint(x: frame.origin.x + frame.size.width, y: frame.origin.y + frame.size.height - radisu))  // Bottom right
        path.addQuadCurve(to: CGPoint(x: frame.origin.x + frame.size.width - radisu, y: frame.origin.y + frame.size.height), controlPoint: CGPoint(x: frame.origin.x + frame.size.width, y: frame.origin.y + frame.size.height)) // Bottom right arc
        path.addLine(to: CGPoint(x: frame.origin.x + radisu, y: frame.origin.y + frame.size.height))  // Bottom left
        path.addQuadCurve(to: CGPoint(x: frame.origin.x, y: frame.origin.y + frame.size.height - radisu), controlPoint: CGPoint(x: frame.origin.x, y: frame.origin.y + frame.size.height)) // Bottom left arc
        path.addLine(to: CGPoint(x: frame.origin.x, y: frame.origin.y + radisu))  // Top left
        path.addQuadCurve(to: CGPoint(x: frame.origin.x + radisu, y: frame.origin.y), controlPoint: CGPoint(x: frame.origin.x, y: frame.origin.y)) // Top left arc
        path.close()

        return path
    }

When using this with stroke you need to also inset the frame by half of the line width. This is a snippet from "draw rect" procedure but can be applied anywhere:

        UIColor.red.setStroke()
        let lineWidth: CGFloat = 5.0
        let path = roundedRectPath(inRect: bounds.insetBy(dx: lineWidth*0.5, dy: lineWidth*0.5), radiusConstrainedTo: 30.0)
        path.lineWidth = lineWidth
        path.stroke()

Notice the bounds.insetBy(dx: lineWidth*0.5, dy: lineWidth*0.5).

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