ios中圖片展開的幾種方式

標籤：

1. UIImageView整體展開

UIImageView-contentMode

typedef NS_ENUM(NSInteger, UIViewContentMode) {    UIViewContentModeScaleToFill,         // 預設 展開（會變形）    UIViewContentModeScaleAspectFit,      // 等比例展開    UIViewContentModeScaleAspectFill,     // 等比例填充    UIViewContentModeRedraw,              // redraw on bounds change (這個不清楚)     UIViewContentModeCenter,              // 下面的就是不展開按位置顯示了    UIViewContentModeTop,    UIViewContentModeBottom,    UIViewContentModeLeft,    UIViewContentModeRight,    UIViewContentModeTopLeft,    UIViewContentModeTopRight,    UIViewContentModeBottomLeft,    UIViewContentModeBottomRight,};

demo：https://github.com/vitoziv/VICMAImageView 

2. UIImage局部展開

// 按4邊間距顯示不展開的地區- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets NS_AVAILABLE_IOS(5_0); // 按2點展開- (UIImage *)stretchableImageWithLeftCapWidth:(NSInteger)leftCapWidth topCapHeight:(NSInteger)topCapHeight;

- (UIImage *)resizableImageWithCapInsets:(UIEdgeInsets)capInsets resizingMode:(UIImageResizingMode)resizingMode;// 展開模式typedef NS_ENUM(NSInteger, UIImageResizingMode) {    UIImageResizingModeTile,//進列區域複製模式展開    UIImageResizingModeStretch,//進行漸層複製模式展開};

3.UIImage修改大小

//內縮放，一條變等於最長邊，另外一條小於等於最長邊- (UIImage *)scaleToSize:(CGSize)newSize {    CGFloat width = self.size.width;    CGFloat height= self.size.height;    CGFloat newSizeWidth = newSize.width;    CGFloat newSizeHeight= newSize.height;    if (width <= newSizeWidth &&        height <= newSizeHeight) {        return self;    }        if (width == 0 || height == 0 || newSizeHeight == 0 || newSizeWidth == 0) {        return nil;    }    CGSize size;    if (width / height > newSizeWidth / newSizeHeight) {        size = CGSizeMake(newSizeWidth, newSizeWidth * height / width);    } else {        size = CGSizeMake(newSizeHeight * width / height, newSizeHeight);    }    return [self drawImageWithSize:size];}- (UIImage *)drawImageWithSize: (CGSize)size {    CGSize drawSize = CGSizeMake(floor(size.width), floor(size.height));    UIGraphicsBeginImageContext(drawSize);        [self drawInRect:CGRectMake(0, 0, drawSize.width, drawSize.height)];    UIImage *newImage = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    return newImage;}

ios中圖片展開的幾種方式