How to catch command down?

AppleScript In Xcode
#1

I would like to unhide some control views in a utility panel when the command key is pressed (without any character key associated with the command key).

I thought the flagsChanged method was a good candidate for this but I don’t know how to make it work.

A clue?

#2

You’ll probably need to override the -keyDown: method and check what key’s pressed. Probably on the window.

#3

Hi Shane,

keyDown seems to triggers only if a character key is associated (e.g. command+C).

I’ve sub-classed NSPanel.
In the .m file I added:

 - (void)flagsChanged:(NSEvent *)theEvent
{
    flags = (theEvent.modifierFlags & NSEventModifierFlagCommand) != 0;
    NSLog(@"Flag changed %d", flags);
    
    [super flagsChanged:theEvent]; -- not sure this is necessary
}

I can see in the Debug Area of Xcode that the code is working:

capture 003
capture 003755×252 29 KB

My problem is that I don’t know how to get those results in the AppDelegate script.

#4

You just have that method call one in your app delegate:

[[NSApp delegate] commandPressed]
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#5

Sorry Shane, I don’t get it.

Where I’m supposed to put this line of code?
I presume it’s not in the AppDelegate.applescript…

Is it in the .h or .m file?

I’m totally lost!

#6

In your subclassed panel:

 - (void)flagsChanged:(NSEvent *)theEvent
{
    flags = (theEvent.modifierFlags & NSEventModifierFlagCommand) != 0;
    if (flags) {
       [[NSApp delegate] commandPressed];
   }
    
    [super flagsChanged:theEvent]; -- this is necessary
}

In your app delegate;

on commandPressed()
-- whatever
#7

It’s throwing an error:

capture 005
capture 005976×1194 167 KB

#8

Add an informal protocol that defines the method. It should go just above the @implementation part:

@interface NSObject (ASCompatability)

- (void)commandPressed;

@end
#9

Not working.

I’ve made a new (testing) app and reconfigured everything, just in case…
The selector remains unknown.

Do we have to declare it in the header file?

#10

It looks like you’ll have to convince the compiler that your app delegate is an NSObject:

- (void)flagsChanged:(NSEvent *)theEvent
{
    if (theEvent.modifierFlags & NSEventModifierFlagCommand) {
        [(NSObject *)[NSApp delegate] commandPressed];
    }
   [super flagsChanged:theEvent];
}
#11

Yeeeesss! This is it!

After hours and hours passed on this, I can’t say how much I’m grateful to you!

:wink:

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