Question

I am developing a Cocoa application and encountered a problem with highlighting. Standard highlighting color in MAC OS X applications is blue, but it doesn’t suit my app, since because of design concepts, I need a green color for highlighting.

I tried to subclass NSTableview and override method

- (void)highlightSelectionInClipRect:(NSRect)clipRect

but it didn’t help.

How to fix this problem?

Answer 1

I am using this, and so far works perfectly:

- (void)highlightSelectionInClipRect:(NSRect)theClipRect
{

        // this method is asking us to draw the hightlights for 
        // all of the selected rows that are visible inside theClipRect

        // 1. get the range of row indexes that are currently visible
        // 2. get a list of selected rows
        // 3. iterate over the visible rows and if their index is selected
        // 4. draw our custom highlight in the rect of that row.

    NSRange         aVisibleRowIndexes = [self rowsInRect:theClipRect];
    NSIndexSet *    aSelectedRowIndexes = [self selectedRowIndexes];
    int             aRow = aVisibleRowIndexes.location;
    int             anEndRow = aRow + aVisibleRowIndexes.length;
    NSGradient *    gradient;
    NSColor *       pathColor;

        // if the view is focused, use highlight color, otherwise use the out-of-focus highlight color
    if (self == [[self window] firstResponder] && [[self window] isMainWindow] && [[self window] isKeyWindow])
    {
        gradient = [[[NSGradient alloc] initWithColorsAndLocations:
                     [NSColor colorWithDeviceRed:(float)62/255 green:(float)133/255 blue:(float)197/255 alpha:1.0], 0.0, 
                     [NSColor colorWithDeviceRed:(float)48/255 green:(float)95/255 blue:(float)152/255 alpha:1.0], 1.0, nil] retain]; //160 80

        pathColor = [[NSColor colorWithDeviceRed:(float)48/255 green:(float)95/255 blue:(float)152/255 alpha:1.0] retain];
    }
    else
    {
        gradient = [[[NSGradient alloc] initWithColorsAndLocations:
                     [NSColor colorWithDeviceRed:(float)190/255 green:(float)190/255 blue:(float)190/255 alpha:1.0], 0.0, 
                     [NSColor colorWithDeviceRed:(float)150/255 green:(float)150/255 blue:(float)150/255 alpha:1.0], 1.0, nil] retain];

        pathColor = [[NSColor colorWithDeviceRed:(float)150/255 green:(float)150/255 blue:(float)150/255 alpha:1.0] retain];
    }

        // draw highlight for the visible, selected rows
    for (aRow; aRow < anEndRow; aRow++)
    {
        if([aSelectedRowIndexes containsIndex:aRow])
        {
            NSRect aRowRect = NSInsetRect([self rectOfRow:aRow], 1, 4); //first is horizontal, second is vertical
            NSBezierPath * path = [NSBezierPath bezierPathWithRoundedRect:aRowRect xRadius:4.0 yRadius:4.0]; //6.0
                [path setLineWidth: 2];
                [pathColor set];
                [path stroke];

            [gradient drawInBezierPath:path angle:90];
        }
    }
}