在UITableViewCell的附件视图中使用UIImageView

Question

I am trying to use a custom image for the UIAccessoryView, however I can't seem to get it to work. When the table view launches, it doesn't update with any of the images. My code is the following:

- (UITableViewCell *) tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *tableViewCell = [tableView dequeueReusableCellWithIdentifier:@"Cell"];
    MenuItem *menuItem = [self.menuItems objectAtIndex:indexPath.row];

    if (!tableViewCell)
    {
        tableViewCell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:@"Cell"];
        tableViewCell.textLabel.font = [UIFont fontWithName: CaptionDistractionBodyFontName size: 15];
        imageView.contentMode = UIViewContentModeCenter;
        tableViewCell.accessoryView = [[UIImageView alloc] initWithImage:nil];
    }

    tableViewCell.textLabel.text = menuItem.name;

    UIImageView *imageView = (UIImageView*)tableViewCell.accessoryView;
    imageView.image = nil;

    if (menuItem.type == MenuItemTypeCheckMark)
    {
        if (menuItem.isCheckMarked)
        {
            imageView.image = [UIImage imageNamed:@"DisclosureViewX"];
        }
    }
    else if (menuItem.type == MenuItemTypeSubmenu)
    {
        imageView.image = [UIImage imageNamed:@"DisclosureViewArrow"];
    }

    return tableViewCell;
}

I've tried a lot of different stuff, ie calling setNeedsLayout , moving the code to a custom UITableViewCell in layoutSubviews and nothing seems to work. Aside from just creating a whole new accessory view myself, what is the correct way to go about this?

Answer 1

尝试做

tableViewCell.accessoryView = [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"DisclosureViewX"]];

Answer 2

Since you initially setup the UIImageView with a nil image, the image view's frame has a zero width and height. You need to reset the frame after assigning an actual image.

imageView.image = [UIImage imageNamed:@"DisclosureViewX"];
imageView.frame = CGRectMake(0, 0, imageView.image.size.width, imageView.image.size.height);

Edit:

Actually it would be even easier to call [imageView sizeToFit] after setting the image instead of setting the frame .

Answer 3

I think your problem is that image view creates with zero size. Use initWithFrame: or initWithImage:, where image is not nil. After created with initWithImage:, image view will have bounds set to image size. A cell will center the accessory view automatically.