objective-c - 如何为 CALayer 设置平铺背景图像？

Question

当我为 IKBrowserView 设置背景时，背景会根据视图大小调整大小：有没有办法将其设置为平铺图像，重复但从不调整大小？

NSImage*    backgroundImage = [NSImage imageNamed:@"wood-bg2.jpg"];
CALayer*    aLayer = [CALayer layer];
//aLayer.contents = backgroundImage;

CIColor *ci = [[CIColor alloc] initWithColor:[NSColor colorWithPatternImage:backgroundImage]];
CGColorSpaceRef cs = [ci colorSpace];
const CGFloat *comps = [ci components];
CGColorRef cgColor = CGColorCreate(cs, comps);

aLayer.backgroundColor = cgColor;
[itemThumbnailImageBrowserView setBackgroundLayer:aLayer];

我已经尝试了注释掉的代码和当前代码，但都没有工作。谢谢

Answer 1

有一种方法NSColor：

+ (NSColor *)colorWithPatternImage:(NSImage *)image

所以你可以做这样的事情：

NSImage*    backgroundImage = [NSImage imageNamed:@"wood-bg2.jpg"];
CALayer*    aLayer = [CALayer layer];
aLayer.backgroundColor = [[NSColor colorWithPatternImage:backgroundImage] CGColor]; // - (CGColor) CGColor; is only available in OS X 10.8 and later
[itemThumbnailImageBrowserView setBackgroundLayer:aLayer];

---

OS X 10.8 及更低版本的更新

转换NSColor为CGColor（未测试）：

CIColor *ci = [[CIColor alloc] initWithColor:[NSColor colorWithPatternImage:backgroundImage]];
CGColorSpaceRef cs = [ci colorSpace];
const CGFloat *comps = [ci components];
CGColorRef cgColor = CGColorCreate(cs, comps);