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UIKit Framework Reference UIButton Class Reference

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UIButton

Import Statement


Swift

import UIKit

Objective-C

@import UIKit;

Availability


Available in iOS 2.0 and later.

An instance of the UIButton class implements a button on the touch screen. A button intercepts touch events and sends an action message to a target object when tapped. Methods for setting the target and action are inherited from UIControl. This class provides methods for setting the title, image, and other appearance properties of a button. By using these accessors, you can specify a different appearance for each button state.

For information about basic view behaviors, see View Programming Guide for iOS.

For more information about appearance and behavior configuration, see Buttons.

  • Creates and returns a new button of the specified type.

    Declaration

    Swift

    class func buttonWithType(_ buttonType: UIButtonType) -> AnyObject

    Objective-C

    + (id)buttonWithType:(UIButtonType)buttonType

    Parameters

    buttonType

    The button type. See UIButtonType for the possible values.

    Return Value

    A newly created button.

    Discussion

    This method is a convenience constructor for creating button objects with specific configurations. If you subclass UIButton, this method does not return an instance of your subclass. If you want to create an instance of a specific subclass, you must alloc/init the button directly.

    When creating a custom button—that is a button with the type UIButtonTypeCustom—the frame of the button is set to (0, 0, 0, 0) initially. Before adding the button to your interface, you should update the frame to a more appropriate value.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • A view that displays the value of the currentTitle property for a button. (read-only)

    Declaration

    Swift

    var titleLabel: UILabel? { get }

    Objective-C

    @property(nonatomic, readonly, retain) UILabel *titleLabel

    Discussion

    Although this property is read-only, its own properties are read/write. Use these properties primarily to configure the text of the button. For example:

    Swift

    • let button = UIButton.buttonWithType(.System) as UIButton
    • button.titleLabel.font = UIFont.systemFontOfSize(12)
    • button.titleLabel.lineBreakMode = .ByTruncatingTail

    Objective-C

    • UIButton *button = [UIButton buttonWithType: UIButtonTypeSystem];
    • button.titleLabel.font = [UIFont systemFontOfSize: 12];
    • button.titleLabel.lineBreakMode = NSLineBreakByTruncatingTail;

    Do not use the label object to set the text color or the shadow color. Instead, use the setTitleColor:forState: and setTitleShadowColor:forState: methods of this class to make those changes.

    The titleLabel property returns a value even if the button has not been displayed yet. The value of the property is nil for system buttons.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 3.0 and later.

    See Also

    currentTitle

  • Returns the title associated with the specified state.

    Declaration

    Swift

    func titleForState(_ state: UIControlState) -> String?

    Objective-C

    - (NSString *)titleForState:(UIControlState)state

    Parameters

    state

    The state that uses the title. The possible values are described in UIControlState.

    Return Value

    The title for the specified state. If no title has been set for the specific state, this method returns the title associated with the UIControlStateNormal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Sets the title to use for the specified state.

    Declaration

    Swift

    func setTitle(_ title: String?, forState state: UIControlState)

    Objective-C

    - (void)setTitle:(NSString *)title forState:(UIControlState)state

    Parameters

    title

    The title to use for the specified state.

    state

    The state that uses the specified title. The possible values are described in UIControlState.

    Discussion

    Use this method to set the title for the button. The title you specify derives its formatting from the button’s associated label object. If you set both a title and an attributed title for the button, the button prefers the use of the attributed title over this one.

    At a minimum, you should set the value for the normal state. If a title is not specified for a state, the default behavior is to use the title associated with the UIControlStateNormal state. If the value for UIControlStateNormal is not set, then the property defaults to a system value.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the styled title associated with the specified state.

    Declaration

    Swift

    func attributedTitleForState(_ state: UIControlState) -> NSAttributedString?

    Objective-C

    - (NSAttributedString *)attributedTitleForState:(UIControlState)state

    Parameters

    state

    The state that uses the styled title. The possible values are described in UIControlState.

    Return Value

    The title for the specified state. If no attributed title has been set for the specific state, this method returns the attributed title associated with the UIControlStateNormal state. If no attributed title has been set for UIControlStateNormal, returns nil.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 6.0 and later.

  • Sets the styled title to use for the specified state.

    Declaration

    Swift

    func setAttributedTitle(_ title: NSAttributedString!, forState state: UIControlState)

    Objective-C

    - (void)setAttributedTitle:(NSAttributedString *)title forState:(UIControlState)state

    Parameters

    title

    The styled text string so use for the title.

    state

    The state that uses the specified title. The possible values are described in UIControlState.

    Discussion

    Use this method to set the title of the button, including any relevant formatting information. If you set both a title and an attributed title for the button, the button prefers the use of the attributed title.

    At a minimum, you should set the value for the normal state. If a title is not specified for a state, the default behavior is to use the title associated with the UIControlStateNormal state. If the value for UIControlStateNormal is not set, then the property defaults to a system value.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 6.0 and later.

  • Returns the title color used for a state.

    Declaration

    Swift

    func titleColorForState(_ state: UIControlState) -> UIColor?

    Objective-C

    - (UIColor *)titleColorForState:(UIControlState)state

    Parameters

    state

    The state that uses the title color. The possible values are described in UIControlState.

    Return Value

    The color of the title for the specified state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Sets the color of the title to use for the specified state.

    Declaration

    Swift

    func setTitleColor(_ color: UIColor?, forState state: UIControlState)

    Objective-C

    - (void)setTitleColor:(UIColor *)color forState:(UIControlState)state

    Parameters

    color

    The color of the title to use for the specified state.

    state

    The state that uses the specified color. The possible values are described in UIControlState.

    Discussion

    In general, if a property is not specified for a state, the default is to use the UIControlStateNormal value. If the UIControlStateNormal value is not set, then the property defaults to a system value. Therefore, at a minimum, you should set the value for the normal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the shadow color of the title used for a state.

    Declaration

    Swift

    func titleShadowColorForState(_ state: UIControlState) -> UIColor?

    Objective-C

    - (UIColor *)titleShadowColorForState:(UIControlState)state

    Parameters

    state

    The state that uses the title shadow color. The possible values are described in UIControlState.

    Return Value

    The color of the title’s shadow for the specified state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Sets the color of the title shadow to use for the specified state.

    Declaration

    Swift

    func setTitleShadowColor(_ color: UIColor?, forState state: UIControlState)

    Objective-C

    - (void)setTitleShadowColor:(UIColor *)color forState:(UIControlState)state

    Parameters

    color

    The color of the title shadow to use for the specified state.

    state

    The state that uses the specified color. The possible values are described in UIControlState.

    Discussion

    In general, if a property is not specified for a state, the default is to use the UIControlStateNormal value. If the UIControlStateNormal value is not set, then the property defaults to a system value. Therefore, at a minimum, you should set the value for the normal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • A Boolean value that determines whether the title shadow changes when the button is highlighted.

    Declaration

    Swift

    var reversesTitleShadowWhenHighlighted: Bool

    Objective-C

    @property(nonatomic) BOOL reversesTitleShadowWhenHighlighted

    Discussion

    If YEStrue, the shadow changes from engrave to emboss appearance when highlighted. The default value is NOfalse.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • A Boolean value that determines whether the image changes when the button is highlighted.

    Declaration

    Swift

    var adjustsImageWhenHighlighted: Bool

    Objective-C

    @property(nonatomic) BOOL adjustsImageWhenHighlighted

    Discussion

    If YEStrue, the image is drawn lighter when the button is highlighted. The default value is YEStrue.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • A Boolean value that determines whether the image changes when the button is disabled.

    Declaration

    Swift

    var adjustsImageWhenDisabled: Bool

    Objective-C

    @property(nonatomic) BOOL adjustsImageWhenDisabled

    Discussion

    If YEStrue, the image is drawn darker when the button is disabled. The default value is YEStrue.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • A Boolean value that determines whether tapping the button causes it to glow.

    Declaration

    Swift

    var showsTouchWhenHighlighted: Bool

    Objective-C

    @property(nonatomic) BOOL showsTouchWhenHighlighted

    Discussion

    If YEStrue, the button glows when tapped; otherwise, it does not. The image and button behavior is not changed by the glow. The default value is NOfalse.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the background image used for a button state.

    Declaration

    Swift

    func backgroundImageForState(_ state: UIControlState) -> UIImage?

    Objective-C

    - (UIImage *)backgroundImageForState:(UIControlState)state

    Parameters

    state

    The state that uses the background image. Possible values are described in UIControlState.

    Return Value

    The background image used for the specified state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the image used for a button state.

    Declaration

    Swift

    func imageForState(_ state: UIControlState) -> UIImage?

    Objective-C

    - (UIImage *)imageForState:(UIControlState)state

    Parameters

    state

    The state that uses the image. Possible values are described in UIControlState.

    Return Value

    The image used for the specified state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Sets the background image to use for the specified button state.

    Declaration

    Swift

    func setBackgroundImage(_ image: UIImage?, forState state: UIControlState)

    Objective-C

    - (void)setBackgroundImage:(UIImage *)image forState:(UIControlState)state

    Parameters

    image

    The background image to use for the specified state.

    state

    The state that uses the specified image. The values are described in UIControlState.

    Discussion

    In general, if a property is not specified for a state, the default is to use the UIControlStateNormal value. If the UIControlStateNormal value is not set, then the property defaults to a system value. Therefore, at a minimum, you should set the value for the normal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Sets the image to use for the specified state.

    Declaration

    Swift

    func setImage(_ image: UIImage?, forState state: UIControlState)

    Objective-C

    - (void)setImage:(UIImage *)image forState:(UIControlState)state

    Parameters

    image

    The image to use for the specified state.

    state

    The state that uses the specified title. The values are described in UIControlState.

    Discussion

    In general, if a property is not specified for a state, the default is to use the UIControlStateNormal value. If the UIControlStateNormal value is not set, then the property defaults to a system value. Therefore, at a minimum, you should set the value for the normal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • tintColor tintColor Property

    The tint color to apply to the button title and image.

    Declaration

    Swift

    var tintColor: UIColor?

    Objective-C

    @property(nonatomic, retain) UIColor *tintColor

    Discussion

    In iOS v7.0, all subclasses of UIView derive their behavior for tintColor from the base class. See the discussion of tintColor at the UIView level for more information.

    This property has no default effect for buttons with type UIButtonTypeCustom. For custom buttons, you must implement any behavior related to tintColor yourself.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 5.0 and later.

  • The inset or outset margins for the rectangle surrounding all of the button’s content.

    Declaration

    Swift

    var contentEdgeInsets: UIEdgeInsets

    Objective-C

    @property(nonatomic) UIEdgeInsets contentEdgeInsets

    Discussion

    Use this property to resize and reposition the effective drawing rectangle for the button content. The content comprises the button image and button title. You can specify a different value for each of the four insets (top, left, bottom, right). A positive value shrinks, or insets, that edge—moving it closer to the center of the button. A negative value expands, or outsets, that edge. Use the UIEdgeInsetsMake function to construct a value for this property. The default value is UIEdgeInsetsZero.

    The button uses this property to determine intrinsicContentSize and sizeThatFits:.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The inset or outset margins for the rectangle around the button’s title text.

    Declaration

    Swift

    var titleEdgeInsets: UIEdgeInsets

    Objective-C

    @property(nonatomic) UIEdgeInsets titleEdgeInsets

    Discussion

    Use this property to resize and reposition the effective drawing rectangle for the button title. You can specify a different value for each of the four insets (top, left, bottom, right). A positive value shrinks, or insets, that edge—moving it closer to the center of the button. A negative value expands, or outsets, that edge. Use the UIEdgeInsetsMake function to construct a value for this property. The default value is UIEdgeInsetsZero.

    The insets you specify are applied to the title rectangle after that rectangle has been sized to fit the button’s text. Thus, positive inset values may actually clip the title text.

    This property is used only for positioning the title during layout. The button does not use this property to determine intrinsicContentSize and sizeThatFits:.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The inset or outset margins for the rectangle around the button’s image.

    Declaration

    Swift

    var imageEdgeInsets: UIEdgeInsets

    Objective-C

    @property(nonatomic) UIEdgeInsets imageEdgeInsets

    Discussion

    Use this property to resize and reposition the effective drawing rectangle for the button image. You can specify a different value for each of the four insets (top, left, bottom, right). A positive value shrinks, or insets, that edge—moving it closer to the center of the button. A negative value expands, or outsets, that edge. Use the UIEdgeInsetsMake function to construct a value for this property. The default value is UIEdgeInsetsZero.

    This property is used only for positioning the image during layout. The button does not use this property to determine intrinsicContentSize and sizeThatFits:.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The button type. (read-only)

    Declaration

    Swift

    var buttonType: UIButtonType { get }

    Objective-C

    @property(nonatomic, readonly) UIButtonType buttonType

    Discussion

    See UIButtonType for the possible values.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The current title that is displayed on the button. (read-only)

    Declaration

    Swift

    var currentTitle: String? { get }

    Objective-C

    @property(nonatomic, readonly, retain) NSString *currentTitle

    Discussion

    The value for this property is set automatically whenever the button state changes. For states that do not have a custom title string associated with them, this method returns the title that is currently displayed, which is typically the one associated with the UIControlStateNormal state. The value may be nil.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The current styled title that is displayed on the button. (read-only)

    Declaration

    Swift

    var currentAttributedTitle: NSAttributedString? { get }

    Objective-C

    @property(nonatomic, readonly, retain) NSAttributedString *currentAttributedTitle

    Discussion

    The value for this property reflects the title associated with the control’s current state. For states that do not have a custom title string associated with them, this method returns the attributed title that is currently displayed, which is typically the one associated with the UIControlStateNormal state.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 6.0 and later.

  • The color used to display the title. (read-only)

    Declaration

    Swift

    var currentTitleColor: UIColor! { get }

    Objective-C

    @property(nonatomic, readonly, retain) UIColor *currentTitleColor

    Discussion

    This value is guaranteed not to be nil. The default value is white.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The color of the title’s shadow. (read-only)

    Declaration

    Swift

    var currentTitleShadowColor: UIColor? { get }

    Objective-C

    @property(nonatomic, readonly, retain) UIColor *currentTitleShadowColor

    Discussion

    The default value is white.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The current image displayed on the button. (read-only)

    Declaration

    Swift

    var currentImage: UIImage? { get }

    Objective-C

    @property(nonatomic, readonly, retain) UIImage *currentImage

    Discussion

    This value can be nil.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • The current background image displayed on the button. (read-only)

    Declaration

    Swift

    var currentBackgroundImage: UIImage? { get }

    Objective-C

    @property(nonatomic, readonly, retain) UIImage *currentBackgroundImage

    Discussion

    This value can be nil.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

    See Also

    currentImage

  • imageView imageView Property

    The button’s image view. (read-only)

    Declaration

    Swift

    var imageView: UIImageView? { get }

    Objective-C

    @property(nonatomic, readonly, retain) UIImageView *imageView

    Discussion

    Although this property is read-only, its own properties are read/write. Use these properties to configure the appearance and behavior of the button’s view. For example:

    Swift

    • let button = UIButton.buttonWithType(.System) as UIButton
    • button.imageView.exclusiveTouch = true;

    Objective-C

    • UIButton *button = [UIButton buttonWithType: UIButtonTypeSystem];
    • button.imageView.exclusiveTouch = YES;

    The imageView property returns a value even if the button has not been displayed yet. The value of the property is nil for system buttons.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 3.0 and later.

  • Returns the rectangle in which the receiver draws its background.

    Declaration

    Swift

    func backgroundRectForBounds(_ bounds: CGRect) -> CGRect

    Objective-C

    - (CGRect)backgroundRectForBounds:(CGRect)bounds

    Parameters

    bounds

    The bounding rectangle of the receiver.

    Return Value

    The bounds rectangle in which to draw any standard button content.

    Discussion

    The default implementation of this method returns the value in the bounds parameter. This rectangle represents the area in which the button draws its standard background content. Subclasses that provide custom background adornments can override this method and return a modified bounds rectangle to prevent the button from drawing over any custom content.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the rectangle in which the receiver draws its entire content.

    Declaration

    Swift

    func contentRectForBounds(_ bounds: CGRect) -> CGRect

    Objective-C

    - (CGRect)contentRectForBounds:(CGRect)bounds

    Parameters

    bounds

    The bounding rectangle for the receiver.

    Return Value

    The rectangle in which the receiver draws its entire content.

    Discussion

    The content rectangle is the area needed to display the image and title including any padding and adjustments for alignment and other settings.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the rectangle in which the receiver draws its title.

    Declaration

    Swift

    func titleRectForContentRect(_ contentRect: CGRect) -> CGRect

    Objective-C

    - (CGRect)titleRectForContentRect:(CGRect)contentRect

    Parameters

    contentRect

    The content rectangle for the receiver.

    Return Value

    The rectangle in which the receiver draws its title.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • Returns the rectangle in which the receiver draws its image.

    Declaration

    Swift

    func imageRectForContentRect(_ contentRect: CGRect) -> CGRect

    Objective-C

    - (CGRect)imageRectForContentRect:(CGRect)contentRect

    Parameters

    contentRect

    The content rectangle for the receiver.

    Return Value

    The rectangle in which the receiver draws its image.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.

  • font font (iOS 3.0) Property

    The font used to display text on the button.

    Deprecation Statement

    Use the font property of the titleLabel instead.

    Declaration

    Objective-C

    @property(nonatomic, retain) UIFont *font

    Discussion

    If nil, a system font is used. The default value is nil.

    Import Statement

    Objective-C

    @import UIKit;

    Availability

    Available in iOS 2.0 and later.

    Deprecated in iOS 3.0.

    See Also

    titleLabel

  • lineBreakMode lineBreakMode (iOS 3.0) Property

    The line break mode to use when drawing text.

    Deprecation Statement

    Use the lineBreakMode property of the titleLabel instead.

    Declaration

    Objective-C

    @property(nonatomic) NSLineBreakMode lineBreakMode

    Discussion

    This property is one of the constants described in the UILineBreakMode enumeration in NSString UIKit Additions Reference. The default value is UILineBreakModeMiddleTruncation.

    Import Statement

    Objective-C

    @import UIKit;

    Availability

    Available in iOS 2.0 and later.

    Deprecated in iOS 3.0.

    See Also

    titleLabel

  • The offset of the shadow used to display the receiver’s title.

    Deprecation Statement

    Use the shadowOffset property of the titleLabel instead.

    Declaration

    Objective-C

    @property(nonatomic) CGSize titleShadowOffset

    Discussion

    The horizontal and vertical offset values, specified using the width and height fields of the CGSize data type. Positive values always extend up and to the right from the user's perspective. The default value is CGSizeZero.

    Import Statement

    Objective-C

    @import UIKit;

    Availability

    Available in iOS 2.0 and later.

    Deprecated in iOS 3.0.

    See Also

    titleLabel

Data Types

  • Specifies the style of a button.

    Declaration

    Swift

    enum UIButtonType : Int { case Custom case System case DetailDisclosure case InfoLight case InfoDark case ContactAdd }

    Objective-C

    typedef enum { UIButtonTypeCustom = 0, UIButtonTypeSystem, UIButtonTypeDetailDisclosure, UIButtonTypeInfoLight, UIButtonTypeInfoDark, UIButtonTypeContactAdd, UIButtonTypeRoundedRect, } UIButtonType;

    Constants

    • Custom

      UIButtonTypeCustom

      No button style.

      Available in iOS 2.0 and later.

    • System

      UIButtonTypeSystem

      A system style button, such as those shown in navigation bars and toolbars.

      Available in iOS 7.0 and later.

    • DetailDisclosure

      UIButtonTypeDetailDisclosure

      A detail disclosure button.

      Available in iOS 2.0 and later.

    • InfoLight

      UIButtonTypeInfoLight

      An information button that has a light background.

      Available in iOS 2.0 and later.

    • InfoDark

      UIButtonTypeInfoDark

      An information button that has a dark background.

      Available in iOS 2.0 and later.

    • ContactAdd

      UIButtonTypeContactAdd

      A contact add button.

      Available in iOS 2.0 and later.

    • UIButtonTypeRoundedRect

      UIButtonTypeRoundedRect

      A rounded-rectangle style button.

      Use UIButtonTypeSystem instead.

      Deprecated in iOS 7.0.

    Import Statement

    Objective-C

    @import UIKit;

    Swift

    import UIKit

    Availability

    Available in iOS 2.0 and later.