How to change the background color of a UIButton w

2019-01-01 09:39发布

问题:

At some point in my app I have a highlighted UIButton (for example when a user has his finger on the button) and I need to change the background color while the button is highlighted (so while the finger of the user is still on the button).

I tried the following:

_button.backgroundColor = [UIColor redColor];

But it is not working. The color remains the same. I tried the same piece of code when the button is not highlighted and it works fine. I also tried calling -setNeedsDisplay after changing the color, it didn\'t have any effect.

How to force the button to change the background color?

回答1:

You can override UIButton\'s setHighlighted method.

Objective-C

- (void)setHighlighted:(BOOL)highlighted {
    [super setHighlighted:highlighted];

    if (highlighted) {
        self.backgroundColor = UIColorFromRGB(0x387038);
    } else {
        self.backgroundColor = UIColorFromRGB(0x5bb75b);
    }
}

Swift 3.0 and Swift 4.1

override open var isHighlighted: Bool {
    didSet {
        backgroundColor = isHighlighted ? UIColor.black : UIColor.white
    }
}


回答2:

Not sure if this sort of solves what you\'re after, or fits with your general development landscape but the first thing I would try would be to change the background colour of the button on the touchDown event.

Option 1:

You would need two events to be capture, UIControlEventTouchDown would be for when the user presses the button. UIControlEventTouchUpInside and UIControlEventTouchUpOutside will be for when they release the button to return it to the normal state

UIButton *myButton =  [UIButton buttonWithType:UIButtonTypeCustom];
[myButton setFrame:CGRectMake(10.0f, 10.0f, 100.0f, 20.f)];
[myButton setBackgroundColor:[UIColor blueColor]];
[myButton setTitle:@\"click me:\" forState:UIControlStateNormal];
[myButton setTitle:@\"changed\" forState:UIControlStateHighlighted];
[myButton addTarget:self action:@selector(buttonHighlight:) forControlEvents:UIControlEventTouchDown];
[myButton addTarget:self action:@selector(buttonNormal:) forControlEvents:UIControlEventTouchUpInside];

Option 2:

Return an image made from the highlight colour you want. This could also be a category.

+ (UIImage *)imageWithColor:(UIColor *)color {
   CGRect rect = CGRectMake(0.0f, 0.0f, 1.0f, 1.0f);
   UIGraphicsBeginImageContext(rect.size);
   CGContextRef context = UIGraphicsGetCurrentContext();

   CGContextSetFillColorWithColor(context, [color CGColor]);
   CGContextFillRect(context, rect);

   UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
   UIGraphicsEndImageContext();

   return image;
}

and then change the highlighted state of the button:

[myButton setBackgroundImage:[self imageWithColor:[UIColor greenColor]] forState:UIControlStateHighlighted];


回答3:

There is no need to override highlighted as computed property. You can use property observer to trigger background color change:

override var highlighted: Bool {
    didSet {
        backgroundColor = highlighted ? UIColor.lightGrayColor() : UIColor.whiteColor()
    }
}

Swift 4

override open var isHighlighted: Bool {
    didSet {
        backgroundColor = isHighlighted ? UIColor.lightGray : UIColor.white
    }
}


回答4:

In Swift you can override the accessor of the highlighted (or selected) property rather than overriding the setHighlighted method

override var highlighted: Bool {
        get {
            return super.highlighted
        }
        set {
            if newValue {
                backgroundColor = UIColor.blackColor()
            }
            else {
                backgroundColor = UIColor.whiteColor()
            }
            super.highlighted = newValue
        }
    }


回答5:

An handy generic extension in Swift:

extension UIButton {
    private func imageWithColor(color: UIColor) -> UIImage {
        let rect = CGRectMake(0.0, 0.0, 1.0, 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()

        CGContextSetFillColorWithColor(context, color.CGColor)
        CGContextFillRect(context, rect)

        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image
    }

    func setBackgroundColor(color: UIColor, forUIControlState state: UIControlState) {
        self.setBackgroundImage(imageWithColor(color), forState: state)
    }
}

Swift 3.0

extension UIButton {
    private func imageWithColor(color: UIColor) -> UIImage? {
        let rect = CGRect(x: 0.0, y: 0.0, width: 1.0, height: 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()

        context?.setFillColor(color.cgColor)
        context?.fill(rect)

        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image
    }

    func setBackgroundColor(_ color: UIColor, for state: UIControlState) {
        self.setBackgroundImage(imageWithColor(color: color), for: state)
    }
}


回答6:

Override highlighted variable. Adding @IBInspectable makes you edit the highlighted backgroundColor in storyboard, which is nifty too.

class BackgroundHighlightedButton: UIButton {
    @IBInspectable var highlightedBackgroundColor :UIColor?
    @IBInspectable var nonHighlightedBackgroundColor :UIColor?
    override var highlighted :Bool {
        get {
            return super.highlighted
        }
        set {
            if newValue {
                self.backgroundColor = highlightedBackgroundColor
            }
            else {
                self.backgroundColor = nonHighlightedBackgroundColor
            }
            super.highlighted = newValue
        }
    }
}


回答7:

a more compact solution (based on @aleksejs-mjaliks answer):

Swift 3/4+:

override var isHighlighted: Bool {
    didSet {
        backgroundColor = isHighlighted ? .lightGray : .white
    }
}

Swift 2:

override var highlighted: Bool {
    didSet {
        backgroundColor = highlighted ? UIColor.lightGrayColor() : UIColor.whiteColor()
    }
}

If you don\'t want to override, this is an updated version of @timur-bernikowich\'s answer (Swift 4.2):

extension UIButton {
  func setBackgroundColor(_ color: UIColor, forState controlState: UIControl.State) {
    let colorImage = UIGraphicsImageRenderer(size: CGSize(width: 1, height: 1)).image { _ in
      color.setFill()
      UIBezierPath(rect: CGRect(x: 0, y: 0, width: 1, height: 1)).fill()
    }
    setBackgroundImage(colorImage, for: controlState)
  }
}


回答8:

UIButton extension with Swift 3+ syntax:

extension UIButton {
    func setBackgroundColor(color: UIColor, forState: UIControlState) {
        UIGraphicsBeginImageContext(CGSize(width: 1, height: 1))
        UIGraphicsGetCurrentContext()!.setFillColor(color.cgColor)
        UIGraphicsGetCurrentContext()!.fill(CGRect(x: 0, y: 0, width: 1, height: 1))
        let colorImage = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()
        self.setBackgroundImage(colorImage, for: forState)
    }}

Use it like:

YourButton.setBackgroundColor(color: UIColor.white, forState: .highlighted)

Original Answer: https://stackoverflow.com/a/30604658/3659227



回答9:

You can use this category which add the method setBackgroundColor:forState:

https://github.com/damienromito/UIButton-setBackgroundColor-forState-



回答10:

Here\'s an approach in Swift, using a UIButton extension to add an IBInspectable, called highlightedBackgroundColor. Similar to subclassing, without requiring a subclass.

private var HighlightedBackgroundColorKey = 0
private var NormalBackgroundColorKey = 0

extension UIButton {

    @IBInspectable var highlightedBackgroundColor: UIColor? {
        get {
            return objc_getAssociatedObject(self, &HighlightedBackgroundColorKey) as? UIColor
        }

        set(newValue) {
            objc_setAssociatedObject(self,
                &HighlightedBackgroundColorKey, newValue, UInt(OBJC_ASSOCIATION_RETAIN))
        }
    }

    private var normalBackgroundColor: UIColor? {
        get {
            return objc_getAssociatedObject(self, &NormalBackgroundColorKey) as? UIColor
        }

        set(newValue) {
            objc_setAssociatedObject(self,
                &NormalBackgroundColorKey, newValue, UInt(OBJC_ASSOCIATION_RETAIN))
        }
    }

    override public var backgroundColor: UIColor? {
        didSet {
            if !highlighted {
                normalBackgroundColor = backgroundColor
            }
        }
    }

    override public var highlighted: Bool {
        didSet {
            if let highlightedBackgroundColor = self.highlightedBackgroundColor {
                if highlighted {
                    backgroundColor = highlightedBackgroundColor
                } else {
                    backgroundColor = normalBackgroundColor
                }
            }
        }
    }
}

I hope this helps.



回答11:

My best solution for Swift 3+ without subclassing.

extension UIButton {
  func setBackgroundColor(_ color: UIColor, for state: UIControlState) {
    let rect = CGRect(x: 0, y: 0, width: 1, height: 1)
    UIGraphicsBeginImageContext(rect.size)
    color.setFill()
    UIRectFill(rect)
    let colorImage = UIGraphicsGetImageFromCurrentImageContext()
    UIGraphicsEndImageContext()
    setBackgroundImage(colorImage, for: state)
  }
}

With this extension it\'s easy to manage colors for different states and it will fade your normal color automatically in case highlighted color is not provided.

button.setBackgroundColor(.red, for: .normal)


回答12:

UPDATE:

Use the UIButtonBackgroundColor Swift library.

OLD:

Use the helpers below to create a 1 px x 1 px image with a grayscale fill color:

UIImage *image = ACUTilingImageGray(248/255.0, 1);

or an RGB fill color:

UIImage *image = ACUTilingImageRGB(253/255.0, 123/255.0, 43/255.0, 1);

Then, use that image to set the button\'s background image:

[button setBackgroundImage:image forState:UIControlStateNormal];

Helpers

#pragma mark - Helpers

UIImage *ACUTilingImageGray(CGFloat gray, CGFloat alpha)
{
    return ACUTilingImage(alpha, ^(CGContextRef context) {
        CGContextSetGrayFillColor(context, gray, alpha);
    });
}

UIImage *ACUTilingImageRGB(CGFloat red, CGFloat green, CGFloat blue, CGFloat alpha)
{
    return ACUTilingImage(alpha, ^(CGContextRef context) {
        CGContextSetRGBFillColor(context, red, green, blue, alpha);
    });
}

UIImage *ACUTilingImage(CGFloat alpha, void (^setFillColor)(CGContextRef context))
{
    CGRect rect = CGRectMake(0, 0, 0.5, 0.5);
    UIGraphicsBeginImageContextWithOptions(rect.size, alpha == 1, 0);
    CGContextRef context = UIGraphicsGetCurrentContext();
    setFillColor(context);
    CGContextFillRect(context, rect);
    UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    return image;
}

Note: ACU is the class prefix of my Cocoa Touch Static Library called Acani Utilities, where AC is for Acani, and U is for Utilities.



回答13:

Try this !!!!

For TouchedDown Event set One color and for TouchUpInside set the other.

- (IBAction)touchedDown:(id)sender {
    NSLog(@\"Touched Down\");
    btn1.backgroundColor=[UIColor redColor];
}

- (IBAction)touchUpInside:(id)sender {
    NSLog(@\"TouchUpInside\");
    btn1.backgroundColor=[UIColor whiteColor];    
}


回答14:

Subclass the UIButton and add inspectable properties for convenient use (written in Swift 3.0):

final class SelectableBackgroundButton: UIButton {

    private struct Constants {
        static let animationDuration: NSTimeInterval = 0.1
    }

    @IBInspectable
    var animatedColorChange: Bool = true

    @IBInspectable
    var selectedBgColor: UIColor = UIColor.blackColor().colorWithAlphaComponent(0.2)

    @IBInspectable
    var normalBgColor: UIColor = UIColor.clearColor()

    override var selected: Bool {
        didSet {
            if animatedColorChange {
                UIView.animateWithDuration(Constants.animationDuration) {
                    self.backgroundColor = self.selected ? self.selectedBgColor : self.normalBgColor
                }
            } else {
                self.backgroundColor = selected ? selectedBgColor : normalBgColor
            }
        }
    }

    override var highlighted: Bool {
        didSet {
            if animatedColorChange {
                UIView.animateWithDuration(Constants.animationDuration) {
                    self.backgroundColor = self.highlighted ? self.selectedBgColor : self.normalBgColor
                }
            } else {
                self.backgroundColor = highlighted ? selectedBgColor : normalBgColor
            }
        }
    }
}


回答15:

Try this if you have an image:

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

or see if showsTouchWhenHighlighted is enough for you.



回答16:

You can subclass the UIButton and make a nice forState.

colourButton.h

#import <UIKit/UIKit.h>

@interface colourButton : UIButton

-(void)setBackgroundColor:(UIColor *)backgroundColor forState:(UIControlState)state;

@end

colourButton.m

#import \"colourButton.h\"

@implementation colourButton
{
    NSMutableDictionary *colours;
}

-(id)initWithCoder:(NSCoder *)aDecoder
{
    self = [super initWithCoder:aDecoder];

    // If colours does not exist
    if(!colours)
    {
        colours = [NSMutableDictionary new];  // The dictionary is used to store the colour, the key is a text version of the ENUM
        colours[[NSString stringWithFormat:@\"%lu\", UIControlStateNormal]] = (UIColor*)self.backgroundColor;  // Store the original background colour
    }

    return self;
}

-(void)setBackgroundColor:(UIColor *)backgroundColor forState:(UIControlState)state
{
    // If it is normal then set the standard background here
    if(state & UIControlStateNormal)
    {
        [super setBackgroundColor:backgroundColor];
    }

    // Store the background colour for that state
    colours[[NSString stringWithFormat:@\"%lu\", state]]= backgroundColor;
}

-(void)setHighlighted:(BOOL)highlighted
{
    // Do original Highlight
    [super setHighlighted:highlighted];

    // Highlight with new colour OR replace with orignial
    if (highlighted && colours[[NSString stringWithFormat:@\"%lu\", UIControlStateHighlighted]])
    {
        self.backgroundColor = colours[[NSString stringWithFormat:@\"%lu\", UIControlStateHighlighted]];
    }
    else
    {
        self.backgroundColor = colours[[NSString stringWithFormat:@\"%lu\", UIControlStateNormal]];
    }
}

-(void)setSelected:(BOOL)selected
{
    // Do original Selected
    [super setSelected:selected];

    // Select with new colour OR replace with orignial
    if (selected && colours[[NSString stringWithFormat:@\"%lu\", UIControlStateSelected]])
    {
        self.backgroundColor = colours[[NSString stringWithFormat:@\"%lu\", UIControlStateSelected]];
    }
    else
    {
        self.backgroundColor = colours[[NSString stringWithFormat:@\"%lu\", UIControlStateNormal]];
    }
}

@end

Notes (This is an example, I know there are problems and here are some)

I have used an NSMutableDictionay to store the UIColor for each State, I have to do a nasty text conversion for the Key as the UIControlState is not a nice straight Int. If it where you could init an Array with that many objects and use the State as an index.

Because of this you many have difficulties with e.g. a selected & disabled button, some more logic is needed.

Another problem is if you try and set multiple colours at the same time, I have not tried with a button but if you can do this it may not work

 [btn setBackgroundColor:colour forState:UIControlStateSelected & UIControlStateHighlighted];

I have assumed this is StoryBoard, there is no init, initWithFrame so add them if you need them.



回答17:

I have open-sourced a UIButton subclass, STAButton, to fill in this gaping functionality hole. Available under the MIT license. Works for iOS 7+ (I have not tested with older iOS versions).



回答18:

To solve this problem I created a Category to handle backgroundColor States with UIButtons:
ButtonBackgroundColor-iOS

You can install the category as a pod.

Easy to use with Objective-C

@property (nonatomic, strong) UIButton *myButton;

...

[self.myButton bbc_backgroundColorNormal:[UIColor redColor]
                 backgroundColorSelected:[UIColor blueColor]];

Even more easy to use with Swift:

import ButtonBackgroundColor

...

let myButton:UIButton = UIButton(type:.Custom)

myButton.bbc_backgroundColorNormal(UIColor.redColor(), backgroundColorSelected: UIColor.blueColor())

I recommend you import the pod with:

platform :ios, \'8.0\'
use_frameworks!

pod \'ButtonBackgroundColor\', \'~> 1.0\'

Using use_frameworks! in your Podfile makes easier to use your pods with Swift and objective-C.

IMPORTANT

I also wrote a Blog Post with more information.



回答19:

Use https://github.com/swordray/UIButtonSetBackgroundColorForState

Add to Podfile using CocoaPods

pod \"UIButtonSetBackgroundColorForState\"

Swift

button.setBackgroundColor(.red, forState: .highlighted)

Objective-C

[button setBackgroundColor:[UIColor redColor] forState:UIControlStateHighlighted];


回答20:

Try tintColor:

_button.tintColor = [UIColor redColor];


回答21:

Here is the code in Swift to select for button state:

func imageWithColor(color:UIColor) -> UIImage {
    let rect:CGRect = CGRectMake(0.0, 0.0, 1.0, 1.0)
     UIGraphicsBeginImageContext(rect.size)
    let context:CGContextRef = UIGraphicsGetCurrentContext()!
    CGContextSetFillColorWithColor(context, color.CGColor)
    CGContextFillRect(context, rect)
    let image:UIImage = UIGraphicsGetImageFromCurrentImageContext();
    return image;
}

Example:

    self.button.setImage(self.imageWithColor(UIColor.blackColor()), forState: .Highlighted)


回答22:

Drop it in and you\'re good to go:
*proerty can be set in IB, and if no highlighted background is set, background will not change when pressed

private var highlightedBackgroundColors = [UIButton:UIColor]()
private var unhighlightedBackgroundColors = [UIButton:UIColor]()
extension UIButton {

    @IBInspectable var highlightedBackgroundColor: UIColor? {
        get {
            return highlightedBackgroundColors[self]
        }

        set {
            highlightedBackgroundColors[self] = newValue
        }
    }

    override open var backgroundColor: UIColor? {
        get {
            return super.backgroundColor
        }

        set {
            unhighlightedBackgroundColors[self] = newValue
            super.backgroundColor = newValue
        }
    }

    override open var isHighlighted: Bool {
        get {
            return super.isHighlighted
        }

        set {
            if highlightedBackgroundColor != nil {
                super.backgroundColor = newValue ? highlightedBackgroundColor : unhighlightedBackgroundColors[self]
            }
            super.isHighlighted = newValue
        }
    }
}


回答23:

Below UIIImage extension will generates image object with specified color parameter.

extension UIImage {
    static func imageWithColor(tintColor: UIColor) -> UIImage {
        let rect = CGRect(x: 0, y: 0, width: 1, height: 1)
        UIGraphicsBeginImageContextWithOptions(rect.size, false, 0)
        tintColor.setFill()
        UIRectFill(rect)
        let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return image
       }
    }

An example usage for a button can be applied for the button object as :

setupButton.setBackgroundImage(UIImage.imageWithColor(tintColor: UIColor(displayP3Red: 232/255, green: 130/255, blue: 121/255, alpha: 1.0)), for: UIControlState.highlighted)

setupButton.setBackgroundImage(UIImage.imageWithColor(tintColor: UIColor(displayP3Red: 255/255, green: 194/255, blue: 190/255, alpha: 1.0)), for: UIControlState.normal)


回答24:

class CustomButton: UIButton {

    override var isHighlighted: Bool {
        didSet {
            if (isHighlighted) {
                alpha = 0.5
            }
            else {
                alpha = 1
            }            
        }
    }

}


回答25:

if you won\'t override just set two action touchDown touchUpInside



回答26:

Swift 3:

extension UIButton {
    private func imageWithColor(color: UIColor) -> UIImage {
        let rect = CGRect(x:0.0,y:0.0,width: 1.0,height: 1.0)
        UIGraphicsBeginImageContext(rect.size)
        let context = UIGraphicsGetCurrentContext()

        context!.setFillColor(color.cgColor)
        context!.fill(rect)

        let image = UIGraphicsGetImageFromCurrentImageContext()
        UIGraphicsEndImageContext()

        return image!
    }

    func setBackgroundColor(color: UIColor, forUIControlState state: UIControlState) {
        self.setBackgroundImage(imageWithColor(color: color), for: state)
    }
}