在UITableView中突出显示所选单元格的边框

Question

是否有可能在Objective-c中的UITableViewController中突出显示 所选单元格的边框 ？

Answer 1

You can try to make an custom UIView/UIImageView for the selection with setSelectedBackgroundView:

Here is a example code I use for custom gradient in a custom tableviewcell:

UIView *selctionView = [[[UIView alloc] initWithFrame:CGRectMake(0, 0, self.bounds.size.width, self.bounds.size.height)] autorelease];

CAGradientLayer *gradient = [CAGradientLayer layer];
gradient.frame = selctionView.bounds;
gradient.colors = [NSArray arrayWithObjects:(id)[[UIColor blueColor] CGColor], (id)[[UIColor redColor] CGColor], nil];

[selctionView.layer insertSublayer:gradient atIndex:0];

[self setSelectedBackgroundView:selctionView];

EDIT:

I found out that you also can use the methods:

[test.layer setBorderColor: [[UIColor redColor] CGColor]];
[test.layer setBorderWidth: 1.0]; 

for the layer.

be sure to import QuartzCore.h

else for the whole tableview:

[tableViewController.tableView setSeparatorColor:[UIColor redColor]];

Answer 2

This is really simple, since OS 3.0 just set the background color of the cell in the willDisplayCell method. You must not set the color in the cellForRowAtIndexPath.

This works for both the plain and grouped style :

Code:

• (void)tableView:(UITableView *)tableView willDisplayCell:(UITableViewCell *)cell forRowAtIndexPath:(NSIndexPath *)indexPath { cell.backgroundColor = [UIColor redColor]; }

PS: Here the documentation extract for willDisplayCell :

"A table view sends this message to its delegate just before it uses cell to draw a row, thereby permitting the delegate to customize the cell object before it is displayed. This method gives the delegate a chance to override state-based properties set earlier by the table view, such as selection and background color. After the delegate returns, the table view sets only the alpha and frame properties, and then only when animating rows as they slide in or out."

I've found this information in this post from colionel. Thank him!