UITableViewCell drawRect影响其他单元格

Question

I have a UITableView with custom cells in it.

I want to use the drawRect method to render the cells myself (I'm using a mask to render an image with rounded corner).

Anyway, with the drawRect method in the tableView only draws one cell. All the rest are there they are just invisible. I can tap them but I can't see them.

If I remove the drawRect method then all the cells are visible with the labels showing.

The drawRect method is...

- (void)drawRect:(CGRect)rect
{
    CGContextRef context = UIGraphicsGetCurrentContext();

    CGRect mask = CGRectMake(10, 10, rect.size.width - 20, rect.size.height - 20);

    UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:mask cornerRadius:4];

    CAShapeLayer *maskLayer = [CAShapeLayer layer];
    maskLayer.frame = self.frame;

    maskLayer.path = maskPath.CGPath;

    self.layer.mask = maskLayer;

    if (self.image == nil) {
        CGContextSetFillColorWithColor(context, [UIColor colorWithWhite:0.6 alpha:1.0].CGColor);
        CGContextFillRect(context, rect);
    } else {
        float width = rect.size.width - 20;
        float height = self.image.size.height / self.image.size.width * width;

        CGRect imageRect = CGRectMake((rect.size.width - width) * 0.5, (rect.size.height - height) * 0.5, width, height);
        [self.image drawInRect:imageRect];
    }
}

Am I doing something wrong here?

Also, if I remove the mask then it draws all the cells but I want the mask in there for the rounded corners.

EDIT - removing the image drawing

I edited the drawRect method (which is in the UITableViewCell ) (why would I put it in the tableView?)

Anyway, the new drawRect method is...

- (void)drawRect:(CGRect)rect
{
    if (self.image == nil) {
        CGContextRef context = UIGraphicsGetCurrentContext();

        CGRect mask = CGRectMake(10, 10, rect.size.width - 20, rect.size.height - 20);

        UIBezierPath *maskPath = [UIBezierPath bezierPathWithRoundedRect:mask cornerRadius:4];

        CAShapeLayer *maskLayer = [CAShapeLayer layer];
        maskLayer.frame = self.frame;

        maskLayer.path = maskPath.CGPath;

        self.layer.mask = maskLayer;

        CGContextSetFillColorWithColor(context, [UIColor colorWithWhite:0.7 alpha:1.0].CGColor);
        CGContextFillRect(context, rect);
    }
}

If the image is nil then it renders a grey rectangle in its place. Except it only shows the first cell. The mask seems to stop the other cells from displaying.

Answer 1

You're setting mask layer frame to cell's frame which is in coordinate space of cell's superview - UITableView, so for all cells but the first one actual mask frame will be outside of the cell's bounds. Try to set mask frame to cell's bounds instead:

maskLayer.frame = self.bounds;