UIImageView

作用：专门用于显示图片

常用方法

    // (1)创建
    UIImageView *imageView = [[UIImageView alloc ] init];
    UIImage *image = [UIImage imageNamed:@"image_photo"];
    imageView.image = image;


    // (2)设置圆角
    imageView.layer.masksToBounds = YES;
    imageView.layer.cornerRadius = 10;


    // (3)设置边框颜色和大小
    imageView.layer.borderColor = [UIColor orangeColor].CGColor;
    imageView.layer.borderWidth = 2;


    // (4)contentMode属性：当图片小于imageView的大小处理图片显示

    imageView.contentMode = UIViewContentModeScaleAspectFit;
    /*
     这个属性是用来设置图片的显示方式，如居中、居右，是否缩放等，有以下几个常量可供设定：
     UIViewContentModeScaleToFill,
     UIViewContentModeScaleAspectFit,
     UIViewContentModeScaleAspectFill,
     UIViewContentModeRedraw,
     UIViewContentModeCenter,
     UIViewContentModeTop,
     UIViewContentModeBottom,
     UIViewContentModeLeft,
     UIViewContentModeRight,
     UIViewContentModeTopLeft,
     UIViewContentModeTopRight,
     UIViewContentModeBottomLeft,
     UIViewContentModeBottomRight,
    */


    // (5)为图片添加单击事件：一定要先将userInteractionEnabled置为YES，这样才能响应单击事件
    imageView.userInteractionEnabled = YES;
    UITapGestureRecognizer *singleTap = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(tapImageView:)];
    [imageView addGestureRecognizer:singleTap];


    // (6)或者显示图片


    imageView.hidden = YES;//或者NO;


    // (7)设置透明度
    imageView.alpha =0.5;


    // (8)设置高亮时显示的图片
    imageView.highlightedImage = [UIImage imageNamed:@"image_photo"];


    // 设置正常显示的图片
    imageView.image = [UIImage imageNamed:@"image_photo"];


    // (9)帧动画
    UIImage *image1 = [UIImage imageNamed:@"homeNaviLeftBtn"];
    UIImage *image2 = [UIImage imageNamed:@"homeNaviRightBtn"];
    UIImage *image3 = [UIImage imageNamed:@"image_photo"];
    NSArray *imagesArray = @[image1,image2,image3];
    imageView.animationImages = imagesArray;
    // 设定所有的图片在多少秒内播放完毕
    imageView.animationDuration = [imagesArray count];
    // 不重复播放多少遍，0表示无数遍
    imageView.animationRepeatCount = 0;
    // 开始播放
    [imageView startAnimating];