UILongPressGestureRecognizer处理程序使用不正确的对象

Question

I have a table view, each cell is a custom tablecell view, have a subview, the subview use CoreText draw text. The sub view's class name is CCoreTextView, below are some code of the CCoreTextView

@interface CoreTextView()
{
    CTFrameRef _frame;
}
@end

- (void) initWithFrame:(CGRect)frame 
{
    self = [super initWithFrame:frame];
    if (self) {
        UILongPressGestureRecognizer *myLongPressRecognizer = [[UILongPressGestureRecognizer alloc] initWithTarget:self action:@selector(myLongPressHandle:)];
        [self addGestureRecognizer:myLongPressRecognizer];
        [myLongPressRecognizer release];

    }
}


- (void)drawRect:(CGRect)rect
{
CGContextRef context = UIGraphicsGetCurrentContext();
[self drawText:context];
}

- (void)drawText:(CGContextRef)context
{
    CTFontRef font = CTFontCreateWithName((CFStringRef)self.font.fontName, self.font.pointSize, NULL);
    NSDictionary *attribs = [NSDictionary dictionaryWithObjectsAndKeys:(id)font, kCTFontAttributeName, nil];
    NSMutableAttributedString *attribString = [[NSMutableAttributedString alloc] initWithString:self.text attributes:attribs];
    CFRelease(font);

    CGContextSetTextMatrix(context, CGAffineTransformIdentity);
    CGContextTranslateCTM(context, 0, self.bounds.size.height);
    CGContextScaleCTM(context, 1.0, -1.0);

    CGFloat headIdent = CORETEXTVIEW_HEAD_IDENT;
    CGFloat tailIdent = CORETEXTVIEW_TAIL_IDENT;
    CTParagraphStyleSetting settings[] = {
        {kCTParagraphStyleSpecifierAlignment, sizeof(_textAlignment), &_textAlignment },
        {kCTParagraphStyleSpecifierLineSpacing, sizeof(CGFloat), &_leading},
        {kCTParagraphStyleSpecifierFirstLineHeadIndent, sizeof(CGFloat), &_firstLineHeadIndent},
        {kCTParagraphStyleSpecifierHeadIndent, sizeof(CGFloat), &headIdent},
        {kCTParagraphStyleSpecifierTailIndent, sizeof(CGFloat), &tailIdent}

    };

    CTParagraphStyleRef paragraphStyle = CTParagraphStyleCreate(settings, sizeof(settings) / sizeof(settings[0]));

    CFAttributedStringSetAttribute((CFMutableAttributedStringRef)attribString,
                               CFRangeMake(0, [self.text length]),
                               kCTParagraphStyleAttributeName, 
                               paragraphStyle);
    CFRelease(paragraphStyle);

    CTFramesetterRef framesetter = CTFramesetterCreateWithAttributedString((CFAttributedStringRef)attribString);


    CGRect columnFrame = CGRectMake(0,
                                0,
                                self.bounds.size.width,
                                self.bounds.size.height);
    columnFrame = UIEdgeInsetsInsetRect(columnFrame, UIEdgeInsetsMake(0, CORETEXTVIEW_EDGE_INSET_LEFT, 0, CORETEXTVIEW_EDGE_INSET_RIGHT));

    CGMutablePathRef framePath = CGPathCreateMutable();
    CGPathAddRect(framePath, &CGAffineTransformIdentity, columnFrame);

    CFRange textRange = CFRangeMake(0, 0);
    if (NULL != _frame) {
        CFRelease(_frame);
        _frame = NULL;
    }
    _frame = CTFramesetterCreateFrame(framesetter, textRange, framePath, NULL);
    CTFrameDraw(_frame, context);

    CFRelease(framePath);


    [attribString release];
    CFRelease(framesetter);

}

- (void)myLongPressHandle:(UILongPressGestureRecognizer *)gestureRecognizer
{

    CGPoint point  = [gestureRecognizer locationInView:self];

    NSArray *lineArr    = (NSArray*)CTFrameGetLines(_frame);
    NSInteger lineCount = [lineArr count];
    NSLog(@"lineCount=%d, frame=%@, lineArr=%@", lineCount, _frame, lineArr);
}

The problem is when I press one cell (named CellA) of the table view, do not lift finger, move the finger to another cell(named CellB), i find the longPressHandle still use CellA's subview. NSLog print the content of CellA's subview.

Answer 1

Long-press gestures are continuous. The gesture begins (UIGestureRecognizerStateBegan) when the number of allowable fingers (numberOfTouchesRequired) have been pressed for the specified period (minimumPressDuration) and the touches do not move beyond the allowable range of movement (allowableMovement). The gesture recognizer transitions to the Change state whenever a finger moves, and it ends (UIGestureRecognizerStateEnded) when any of the fingers are lifted.

So you have to check state to detect your

- (void)myLongPressHandle:(UILongPressGestureRecognizer *)gestureRecognizer
{
    if(gesture.state == UIGestureRecognizerStateBegan)
    {
        //if needed do some initial setup or init of views here
    }
    else if(gesture.state == UIGestureRecognizerStateChanged)
    {
        //move your views here.
        [yourView setFrame:];
    }
    else if(gesture.state == UIGestureRecognizerStateEnded)
    {
CGPoint point  = [gestureRecognizer locationInView:self];

NSArray *lineArr    = (NSArray*)CTFrameGetLines(_frame);
NSInteger lineCount = [lineArr count];
NSLog(@"lineCount=%d, frame=%@, lineArr=%@", lineCount, _frame, lineArr);
    }
}

Answer 2

I finally find a way to solve the problem.

1. table view handle the UILongPressGestureRecognizer, in the processor find out which cell is touched.
2. call the cell's touch process function