iOS 获取label上点击位置的字符位置
手势点击事件
-(void)dotap:(UITapGestureRecognizer *)tap
{
CGPoint point=[tap locationInView:self.tableView];
NSIndexPath *indexpath=[self.tableView indexPathForRowAtPoint:point];
if (indexpath) {
ChatTableViewCell *cell=[self.tableView cellForRowAtIndexPath:indexpath];
UILabel *lable=nil;
for (UIView *view in cell.contentView.subviews) {
if ([view isKindOfClass:[UILabel class]]) {
lable=(UILabel*)view;
break;
}
}
CGPoint p = [tap locationInView:cell];
if (CGRectContainsPoint(lable.frame, p)) {
NSError *error = NULL;
NSDataDetector *detector = [NSDataDetector dataDetectorWithTypes:NSTextCheckingTypeLink error:&error];
self.matches = [detector matchesInString:lable.text options:0 range:NSMakeRange(0, lable.text.length)];
//CFIndex index = [self characterIndexAtPoint:[tap locationInView:lable]];
CFIndex index=[self getindexArrayOfStringInLabel:lable Point:[tap locationInView:lable]];
NSLog(@"index=%ld",index);
for (NSTextCheckingResult *match in self.matches) {
if ([match resultType] == NSTextCheckingTypeLink) {
NSRange matchRange = [match range];
if ([self isIndex:index inRange:matchRange]) {
// NSLog(@"点击跳转页面");
NSLog(@"matchRange=%@",[lable.text substringWithRange:matchRange]);
// [[UIApplication sharedApplication] openURL:match.URL];
break;
}
}
}
}
}
}
- (BOOL)isIndex:(CFIndex)index inRange:(NSRange)range {
return index >= range.location && index <= range.location+range.length;
}
#pragma mark -****获取lable中的点击位置的字符的index
-(CFIndex)getindexArrayOfStringInLabel:(UILabel *)label Point:(CGPoint)point
{
NSString *text = [label text];
UIFont *font = [label font];
CGRect rect = [label bounds];
// point = CGPointMake(point.x - rect.origin.x, point.y - rect.origin.y);
// Convert tap coordinates (start at top left) to CT coordinates (start at bottom left) 坐标系反转
point = CGPointMake(point.x, rect.size.height - point.y);
NSUInteger idx = NSNotFound;
CTFontRef myFont = CTFontCreateWithName((CFStringRef)font.fontName,
font.pointSize,
NULL);
NSMutableAttributedString *attStr = [[NSMutableAttributedString alloc] initWithString:text];
[attStr addAttribute:(NSString *)kCTFontAttributeName value:(__bridge id)myFont range:NSMakeRange(0, attStr.length)];
CTFramesetterRef frameSetter = CTFramesetterCreateWithAttributedString((__bridge CFAttributedStringRef)attStr);
CGMutablePathRef path = CGPathCreateMutable();
CGPathAddRect(path, NULL, CGRectMake(0,0,rect.size.width,rect.size.height+20));
CTFrameRef frame = CTFramesetterCreateFrame(frameSetter, CFRangeMake(0, 0), path, NULL);
// NSArray *lines = (__bridge NSArray *)CTFrameGetLines(frame);
CFArrayRef lines = CTFrameGetLines(frame);
NSInteger numberOfLines =CFArrayGetCount(lines);
NSLog(@"numberOfLines=%ld",(long)numberOfLines);
CGPoint lineOrigins[numberOfLines];
CTFrameGetLineOrigins(frame, CFRangeMake(0, numberOfLines), lineOrigins);
for (CFIndex lineIndex = 0; lineIndex < numberOfLines; lineIndex++) {
CGPoint lineOrigin = lineOrigins[lineIndex];
CTLineRef line = CFArrayGetValueAtIndex(lines, lineIndex);
CGFloat ascent, descent, leading, width;
width = CTLineGetTypographicBounds(line, &ascent, &descent, &leading);
CGFloat yMin = floor(lineOrigin.y - descent);
CGFloat yMax = ceil(lineOrigin.y + ascent);
if (point.y > yMax) {
break;
}
if (point.y >= yMin) {
// Check if the point is within this line horizontally
if (point.x >= lineOrigin.x && point.x <= lineOrigin.x + width) {
// Convert CT coordinates to line-relative coordinates
CGPoint relativePoint = CGPointMake(point.x - lineOrigin.x, point.y - lineOrigin.y);
idx = CTLineGetStringIndexForPosition(line, relativePoint);
break;
}
}
}
return idx;
}