这个问题在这里已有答案:
我试图从这里找出CTFrameGetLineOrigins
:CTFrameGetLineOrigins Got Incorrect Origins,并尝试将ObjC转换为Swift。
OBJ-C:
CFArrayRef lines = CTFrameGetLines(frame);
size_t numOfLines = CFArrayGetCount(lines);
CGPoint lineOrigins[numOfLines];
CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), lineOrigins);
迅速:
let lines = CTFrameGetLines(frame)
let numOfLines: size_t = CFArrayGetCount(lines)
let lineOrigins = [CGPoint](repeating: CGPoint.zero, count: numOfLines)
CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), lineOrigins)
但我收到CTFrameGetLineOrigins的第3个参数的错误: 无法将'[CGPoint]'类型的值转换为预期的参数类型'UnsafeMutablePointer'
我如何通过此错误?
实际上我只是将&
添加到参数中并使常量变量。
let lines = CTFrameGetLines(frame)
let numOfLines: size_t = CFArrayGetCount(lines)
var lineOrigins = [CGPoint](repeating: CGPoint.zero, count: numOfLines)
CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), &lineOrigins)
你可以试试
CTFrameGetLineOrigins(frame, CFRangeMake(0, 0), UnsafeMutablePointer(&lineOrigins))
或直接
CTFrameGetLineOrigins(frame, CFRangeMake(0, 0),&lineOrigins)