Question

I have a view-based NSTableView that usually has one column in it. However, at a button press, I want a new column to slide in from the left (very similar to what happens on an iPhone when you click the Edit button in Mail). For now, the view that I want to slide is in a very simple view that draws a solid background: its drawRect: just does

[[NSColor blueColor] set];    
[[NSBezierPath bezierPathWithRect:[self bounds]] fill];

In the delegate for my NSTableView, I have the following:

- (IBAction)buttonPressed:(id)sender
{
        NSTableColumn *newColumn = [[NSTableColumn alloc] initWithIdentifier:@"InPreviewColumn"];
        [newColumn setWidth:40];
        [newColumn setMinWidth:[newColumn width]];
        /* To make up for there not being an insertColumnAt: method, 
           hide the column, add it, and move it to the front before showing it. */
        [newColumn setHidden:YES];

        [availableFontsView beginUpdates];
        [availableFontsView addTableColumn:newColumn];
        [availableFontsView moveColumn:1 toColumn:0];
        [availableFontsView endUpdates];
        [newColumn setHidden:NO];
}

- (NSView *)tableView:(NSTableView *)tableView viewForTableColumn:(NSTableColumn *)tableColumn row:(NSInteger)row
{
   /* ... code for main column ... */
   else if([[tableColumn identifier] isEqualToString:@"InPreviewColumn"])
   {
     USSolidBackgroundView *v = [tableView makeViewWithIdentifier:[tableColumn identifier] owner:self];
     if(!v)
     {
        v = [[[USSolidBackgroundView alloc] initWithFrame:NSMakeRect(0, 0, [tableColumn width], 0)] autorelease];
        [v setIdentifier:[tableColumn identifier]];
        [v setAutoresizingMask:NSViewMinXMargin | NSViewWidthSizable | NSViewMaxXMargin];
     }

     return v;
     }
}

Yet, when I do this, I end up with this result (there’s a big non-blue margin between the blue part of the new column and the start of the main column):

When the additional column isn’t present, there’s no margin so I’m pretty sure that the problem isn’t with the other view (since there’s no margin when it’s the only view displayed).

I’ve used logging statements to verify that solid color view’s bounds always has a width of 40 (in its drawRect:) and, at least when the view is created, the table column has a width of 40 as well.

So where does this margin come from? No matter how I size the column, it seem that only roughly half of it is blue. So, the bigger the column, the bigger the margin.

How do I make the entire extra column blue?

Answer 1

The issue was my being stupid: In the view that draws the font names, I was basing the position on [self frame]. Which is wrong.

[self bounds] is the way to go. Which I knew. Can’t believe I made this mistake. Amateur hour.

If you wander by this question, feel free to vote to close it or flag it or whatever it is that’s supposed to work on Stackoverflow.

My apologies.