Question

我正在尝试使用CoreText和CoreGraphics绘制文本。文字绘制和位置很好，但是我似乎无法更改字体大小。还是字体。我尝试直接使用CFAttributedString设置属性文本，并尝试更改CGContext字体大小设置。这是我的代码

//... (create CGContext)

let textAttrs = [
    kCTFontSizeAttribute as String : 18 as NSNumber
] as CFDictionary

let attrString = CFAttributedStringCreate(kCFAllocatorDefault,
                                          NSString(string: "Hello, world!"),
                                          textAttrs)

let textLine = CTLineCreateWithAttributedString(attrString!)

context.textPosition = CGPoint.zero

CTLineDraw(textLine, context.textPosition)

Answer 1

问题在于属性的定义。首先，我必须定义字体，然后将字体用作字符串的属性。

let fontAttributes = [
    kCTFontFamilyNameAttribute : "Courier",
    kCTFontStyleNameAttribute : "Bold",
    kCTFontSizeAttribute : 18.0
] as NSDictionary

let descriptor = CTFontDescriptorCreateWithAttributes(fontAttributes)
let font = CTFontCreateWithFontDescriptor(descriptor, 0.0, nil)
let attributes = [kCTFontAttributeName : font] as CFDictionary

let attrString = CFAttributedStringCreate(kCFAllocatorDefault,
                                          "Hello, world!" as NSString,
                                          attributes)

CFAttributedString更改字体大小无效

1 个答案: