如何从iPhone sdk上的UIButton获取图像名称？

Question

我正在尝试从自定义按钮获取背景图片的名称。

点击UIButton时调用此方法：

-(void)getButtonImageName:(id)sender{       
    UIButton *resultButton = (UIButton *)sender;
    NSLog(@" The button's image is %@.", resultButton.currentImage);
}

我可以从按钮获取标题和其他属性，但不能获取背景图像名称。

任何人都知道该怎么做？谢谢！

Answer 1

这是获取自定义按钮的当前图像的最简单方法

-(void)yesButtonButtonCliked:(id)sender
{
    UIButton *tmpYes = (UIButton *)sender;
    [self ClearAllButtons:tmpYes.tag:@"YES"];
    UIImage* selectedImg=[UIImage imageNamed:@"checkboxtick.png"];
    if (tmpYes.currentImage == selectedImg ) 
    {

    }
    else
    {
        [tmpYes setImage:[UIImage imageNamed:@"checkboxtick.png"] forState:UIControlStateNormal];
    }
    NSLog(@"Button tag is %d",tmpYes.tag);
}

Answer 2

没有方法可以将UIImage转换为[UIImage imageNamed：]使用的名称。

您是否滥用图片存储数据？ 您尝试使用图像名称完成什么？

---

编辑：

  

我有几个按钮，我想在按下按钮时获取图像名称，切换到另一个视图控制器并使用名称加载该图像。

无需执行此操作，只需传递UIImage实例即可 如果要根据名称显示不同的图像，就像您有缩略图并想要在另一个视图控制器中显示大版本，您必须从数据模型中获取图像名称并将其传递给视图控制器。 /> 你如何决定哪个按钮获取哪个图像？

Answer 3

@fluchtpunkt正如你所说，我有一些带有背景图像的UI按钮的缩略图。会发生的是，我正在为前一个视图控制器中选择的类别创建如下内容。像这样......

if( [strSection isEqualToString:@"animals"] ){
        [button_thumbnail_1 setBackgroundImage:[UIImage imageNamed:@"image1.png"] forState:(UIControlState)normal];
        [button_thumbnail_2 setBackgroundImage:[UIImage imageNamed:@"image2.png"] forState:(UIControlState)normal];
    }
    if( [strSection isEqualToString:@"cars"] ){
        [button_thumbnail_1 setBackgroundImage:[UIImage imageNamed:@"image1.png"] forState:(UIControlState)normal];
        [button_thumbnail_2 setBackgroundImage:[UIImage imageNamed:@"image2.png"] forState:(UIControlState)normal];
    }
}

感谢您的回复

Answer 4

您可以继承UIButton：

//.h
@interface MySpecialButton : UIButton {
    int mySpecialAttribute;
}

@property (nonatomic) int mySpecialAttribute;

- (void) setBackgroundImage;
- (UIImage*) getImage;

@end

并使用您的特殊属性来设置和返回图像名称：

//.m
@implementation LetterButton

@synthesize mySpecialAttribute;
- (void) setBackgroundImage {

    [self setBackgroundImage:[self getImage] forState:UIControlStateNormal];
    [self setBackgroundImage:[self getImage] forState:UIControlStateDisabled];
}

- (UIImage*) getImage {
    NSString *fileName = [NSString stringWithFormat:
            @"My_special_image_%i.png", mySpecialAttribute];

    return [UIImage imageNamed:fileName];
}

@end

在xib中设置按钮的类：

Answer 5

关于Matthias的回答“不需要这样做，只需传递UIImage实例”，这是我的解决方案，其中包含新手的特定代码：

Calling .m:
    -(void) prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
              //Create an instance of the destination controller
                dmImageZoom *dmz = (dmImageZoom *)[segue destinationViewController];
                //Get the tapped button (the image was in a button) into a button object
                UIButton *btnImg= sender;
                //Get the button's image object
                UIImage *img=btnImg.currentImage;
                //Pass the image object to the destination controller's instance variable 
                dmz.imgPassed=img;

Called .h:
@interface dmImageZoom : UIViewController {
    //Instance variable
    UIImage *imgPassed;
}
    //Property for the object that presents the image
    @property (strong, nonatomic) IBOutlet  UIImageView *imgView;
    //Property that enables it to be assigned a value
    @property (strong, nonatomic) IBOutlet  UIImage *imgPassed;

Called .m:

- (void)viewDidLoad
{
    ...
    imgView.contentMode = UIViewContentModeScaleAspectFit;
    //Assign the image to view object
    imgView.image=imgPassed;

Answer 6

 UIButton *senderButton = (UIButton*)sender;    
 if ([senderButton.currentTitle isEqualToString:@"Hello"]) {
            [senderButton setTitle:@"H" forState:UIControlStateNormal];
        }
        else {
            [senderButton setTitle:@"Hello" forState:UIControlStateNormal];
    forState:UIControlStateNormal];
        }

Answer 7

iOS 11 Swift 4.2

@objc func btnWishListAddRemove(_ sender:UIButton){
     let index = sender.tag
     let product_id = array_packageList[index].product_id!

        if sender.currentImage == UIImage(named: "wish list"){
            sender.setImage(UIImage(imageLiteralResourceName: "wishlistfill"), for: .normal)
        }
        else if sender.currentImage == UIImage(named: "wish list fill"){
            sender.setImage(UIImage(imageLiteralResourceName: "wishlist"), for: .normal)
        }
    }