How to make main window visible in Cocoa?

Question

This is kind of a followup to this question. I have the following code:

- (BOOL)applicationShouldHandleReopen:(NSApplication *)app hasVisibleWindows:(BOOL)flag {
    NSLog(@"Has visible windows: %d, main window visible: %d", flag, [[app mainWindow] isVisible]);
    if (!flag) {
        // I need to make mainWindow visible again here. HOW???
        // I tried the following but it has no effect.
        // [[app mainWindow] makeKeyAndOrderFront:self];
        return NO;
    } else {
        return YES;
    }
}

There is [window isVisible] message that I can use to query, but no corresponding setVisible or "show"...

Answer 1

[[app mainWindow] makeKeyAndOrderFront:self]

Answer 2

Assuming you actually have a main window in existence and it's just ordered out for some reason, use makeKeyAndOrderFront:. I would bet, though, that you don't have a main window to talk to, so you'll want to either bring up some window you have a reference to or open a new window.

Answer 3

First, “main window” in Cocoa doesn't mean what I think you think it means. The “main window” is the window that is active. If you don't have any windows ordered in, then no window is the main window, and mainWindow will return nil; if a window is active, it's the main window, but it's not a window that's ordered out (if it were, it couldn't be active).

So, you need to create an outlet to the window that you consider the main window.

isVisible will tell you whether that window is ordered in. If it's ordered out (isVisible returns NO), you'll want to order it in.

Of course, you can't just order it in because that wouldn't specify what order you want it to have. So, you want to order it front.

But making it the frontmost window doesn't count for much if it doesn't have user focus—that is, if it isn't key. So, you want to make it key and order it front.

The message you'll send it to do that is makeKeyAndOrderFront:. Making it key will also make it main.