iphone - CoreText 绘图、接收触摸、触摸坐标困惑

Question

我有一个使用 coretext 绘制一些文本的 View 。一切正常，文本显示在右侧，翻转坐标。但是，我还必须响应特定运行时的触摸，因此我有以下代码，当点击手势识别器触发时会调用它:

- (void)receivedTap:(UITapGestureRecognizer*)recognizer
{
    CGPoint point = [recognizer locationInView:self];
    NSLog(@"point = %@", NSStringFromCGPoint(point));
    CGContextRef context = UIGraphicsGetCurrentContext();

    CFArrayRef lines = CTFrameGetLines(textFrame);
    CFIndex lineCount = CFArrayGetCount(lines);
    CGPoint origins[lineCount];

    CTFrameGetLineOrigins(textFrame, CFRangeMake(0, 0), origins);
    for(CFIndex idx = 0; idx < lineCount; idx++)
    {
        CTLineRef line = CFArrayGetValueAtIndex(lines, idx);
        CGRect lineBounds = CTLineGetImageBounds(line, context);
        lineBounds.origin.y += origins[idx].y;

        if(CGRectContainsPoint(lineBounds, point))
        {
            CFArrayRef runs = CTLineGetGlyphRuns(line);
            for(CFIndex j = 0; j < CFArrayGetCount(runs); j++)
            {
                CTRunRef run = CFArrayGetValueAtIndex(runs, j);
                NSDictionary* attributes = (NSDictionary*)CTRunGetAttributes(run);
                BOOL result = NO;
                NSURL* url = [attributes objectForKey:kJTextViewDataDetectorLinkKey];
                NSString* phoneNumber = [attributes objectForKey:kJTextViewDataDetectorPhoneNumberKey];
                NSDictionary* addressComponents = [attributes objectForKey:kJTextViewDataDetectorPhoneNumberKey];
                if(url)
                {
                    result = [[UIApplication sharedApplication] openURL:url];
                    return;
                }
                else if(phoneNumber)
                {
                    NSURL* url = [NSURL URLWithString:[NSString stringWithFormat:@"tel://%@", phoneNumber]];
                    result = [[UIApplication sharedApplication] openURL:url];
                    return;
                }
                else if(addressComponents)
                {
                    NSMutableString* address = [NSMutableString string];
                    NSString* temp = nil;
                    if((temp = [addressComponents objectForKey:NSTextCheckingStreetKey]))
                        [address appendString:temp];
                    if((temp = [addressComponents objectForKey:NSTextCheckingCityKey]))
                        [address appendString:[NSString stringWithFormat:@"%@%@", ([address length] > 0) ? @", " : @"", temp]];
                    if((temp = [addressComponents objectForKey:NSTextCheckingStateKey]))
                        [address appendString:[NSString stringWithFormat:@"%@%@", ([address length] > 0) ? @", " : @"", temp]];
                    if((temp = [addressComponents objectForKey:NSTextCheckingZIPKey]))
                        [address appendString:[NSString stringWithFormat:@" %@", temp]];
                    if((temp = [addressComponents objectForKey:NSTextCheckingCountryKey]))
                        [address appendString:[NSString stringWithFormat:@"%@%@", ([address length] > 0) ? @", " : @"", temp]];
                    NSString* urlString = [NSString stringWithFormat:@"http://maps.google.com/maps?q=%@", [address stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
                    result = [[UIApplication sharedApplication] openURL:[NSURL URLWithString:urlString]];
                    return;
                }
            }
        }
    }
}

这适用于第一行，例如，我正在对其进行一些数据检测的网址。我点击它，然后 Mobile Safari 如我所料启动。但是，这仅在项目位于第一行时才有效。我在其他行看到带有颜色和下划线的文本(例如地址和电话号码)，并且我已验证适当的数据已附加到字符串中的自定义属性，但是当我点击它们时，没有任何反应。

我知道我必须以某种方式翻转矩形 lineBounds，但我不确定该怎么做。任何帮助将不胜感激。

Answer 1

实际上您需要做的是反向迭代行。例如，尝试替换为以下代码:

NSArray* tempLines = (NSArray*)CTFrameGetLines(textFrame);
CFIndex lineCount = [tempLines count];//CFArrayGetCount(lines);
NSMutableArray* lines = [NSMutableArray arrayWithCapacity:lineCount];
for(id elem in [tempLines reverseObjectEnumerator])
    [lines addObject:elem];
CGPoint origins[lineCount];