Re: modifier-flags with no key pressed and mouseDown 256, why?
Good to know! Thanks for the info. =) Dave On 16 Jan, 2009, at 4:47 PM, Shawn Erickson wrote: On Fri, Jan 16, 2009 at 2:29 PM, Shawn Erickson wrote: On Fri, Jan 16, 2009 at 1:15 PM, Dave DeLong wrote: My understanding is that the modifierFlag "256" means that no other modifiers are pressed. I haven't found it in the docs anywhere, but I believe that you can count on "256" meaning "no flags". Every machine I've tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. Unsafe assumption. You are just lucky that some lower bit (device dependent bit) is being set for you. I know of no documentation that says this bit will always set. Additionally if some other device dependent bit is set your assumption would be broken. As a follow up you are depending on kCGEventFlagMaskNonCoalesced being set if you are checking against a numeric value of 256. IIRC this will not be set for events coming from event sources created with kCGEventSourceStatePrivate and possibly other avenues. -Shawn ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
Thanks for all the input, makes sense. Alex On 16.01.2009, at 23:29, Shawn Erickson wrote: On Fri, Jan 16, 2009 at 1:15 PM, Dave DeLong wrote: My understanding is that the modifierFlag "256" means that no other modifiers are pressed. I haven't found it in the docs anywhere, but I believe that you can count on "256" meaning "no flags". Every machine I've tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. Unsafe assumption. You are just lucky that some lower bit (device dependent bit) is being set for you. I know of no documentation that says this bit will always set. Additionally if some other device dependent bit is set your assumption would be broken. -Shawn ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/lxr%40mac.com This email sent to l...@mac.com smime.p7s Description: S/MIME cryptographic signature ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
On Fri, Jan 16, 2009 at 2:29 PM, Shawn Erickson wrote: > On Fri, Jan 16, 2009 at 1:15 PM, Dave DeLong wrote: >> My understanding is that the modifierFlag "256" means that no other >> modifiers are pressed. I haven't found it in the docs anywhere, but I >> believe that you can count on "256" meaning "no flags". Every machine I've >> tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. > > Unsafe assumption. You are just lucky that some lower bit (device > dependent bit) is being set for you. I know of no documentation that > says this bit will always set. Additionally if some other device > dependent bit is set your assumption would be broken. As a follow up you are depending on kCGEventFlagMaskNonCoalesced being set if you are checking against a numeric value of 256. IIRC this will not be set for events coming from event sources created with kCGEventSourceStatePrivate and possibly other avenues. -Shawn ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
On Fri, Jan 16, 2009 at 1:15 PM, Dave DeLong wrote: > My understanding is that the modifierFlag "256" means that no other > modifiers are pressed. I haven't found it in the docs anywhere, but I > believe that you can count on "256" meaning "no flags". Every machine I've > tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. Unsafe assumption. You are just lucky that some lower bit (device dependent bit) is being set for you. I know of no documentation that says this bit will always set. Additionally if some other device dependent bit is set your assumption would be broken. -Shawn ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
On Fri, Jan 16, 2009 at 1:08 PM, Alexander Reichstadt wrote:
> Hi,
>
> I have a phenomenon I am exploiting but unless I know for sure why it works
> must stop to use. The objective is to make sure that while the mousebuttons
> is being pressed no other modifier key is pressed, if anything is pressed
> the whole method return. Testing for 256 seems to work, why?
>
>NSUInteger modifierFlags = [currentEvent modifierFlags];
>if (modifierFlags!=256) return;
This is a bit field so I personally prefer to work with it as such...
if ((modifierFlags & NSDeviceIndependentModifierFlagsMask)) == 0) {
// no standard modifier is pressed
} else {
// some standard modifier is pressed
}
-Shawn
___
Cocoa-dev mailing list (Cocoa-dev@lists.apple.com)
Please do not post admin requests or moderator comments to the list.
Contact the moderators at cocoa-dev-admins(at)lists.apple.com
Help/Unsubscribe/Update your Subscription:
http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com
This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
Thanks Dave, if someone still has a reference or headerfile or can point me to something from which I can logically deduce that this will hold true, it would help a lot. On 16.01.2009, at 22:15, Dave DeLong wrote: My understanding is that the modifierFlag "256" means that no other modifiers are pressed. I haven't found it in the docs anywhere, but I believe that you can count on "256" meaning "no flags". Every machine I've tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. Dave On Jan 16, 2009, at 2:08 PM, Alexander Reichstadt wrote: Hi, I have a phenomenon I am exploiting but unless I know for sure why it works must stop to use. The objective is to make sure that while the mousebuttons is being pressed no other modifier key is pressed, if anything is pressed the whole method return. Testing for 256 seems to work, why? NSUInteger modifierFlags = [currentEvent modifierFlags]; if (modifierFlags!=256) return; Is there some documentation that supports this test, or do I have to check for all the different keys not to be pressed instead? Thanks Alex ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/lxr%40mac.com This email sent to l...@mac.com smime.p7s Description: S/MIME cryptographic signature ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
On Fri, Jan 16, 2009 at 4:08 PM, Alexander Reichstadt wrote: > Hi, > > I have a phenomenon I am exploiting but unless I know for sure why it works > must stop to use. The objective is to make sure that while the mousebuttons > is being pressed no other modifier key is pressed, if anything is pressed > the whole method return. Testing for 256 seems to work, why? > >NSUInteger modifierFlags = [currentEvent modifierFlags]; >if (modifierFlags!=256) return; > > Is there some documentation that supports this test, or do I have to check > for all the different keys not to be pressed instead? Yes, there is documentation that supports it, the description of the -modifierFlags method: "The lower 16 bits of the modifier flags are reserved for device-dependent bits." In other words, the bottom 16 bits can be anything at any time. Mask them out for this test. Mike ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
Re: modifier-flags with no key pressed and mouseDown 256, why?
My understanding is that the modifierFlag "256" means that no other modifiers are pressed. I haven't found it in the docs anywhere, but I believe that you can count on "256" meaning "no flags". Every machine I've tested this on (I've done a bunch of CGEvent stuff recently) seems to agree. Dave On Jan 16, 2009, at 2:08 PM, Alexander Reichstadt wrote: Hi, I have a phenomenon I am exploiting but unless I know for sure why it works must stop to use. The objective is to make sure that while the mousebuttons is being pressed no other modifier key is pressed, if anything is pressed the whole method return. Testing for 256 seems to work, why? NSUInteger modifierFlags = [currentEvent modifierFlags]; if (modifierFlags!=256) return; Is there some documentation that supports this test, or do I have to check for all the different keys not to be pressed instead? Thanks Alex ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
modifier-flags with no key pressed and mouseDown 256, why?
Hi, I have a phenomenon I am exploiting but unless I know for sure why it works must stop to use. The objective is to make sure that while the mousebuttons is being pressed no other modifier key is pressed, if anything is pressed the whole method return. Testing for 256 seems to work, why? NSUInteger modifierFlags = [currentEvent modifierFlags]; if (modifierFlags!=256) return; Is there some documentation that supports this test, or do I have to check for all the different keys not to be pressed instead? Thanks Alex smime.p7s Description: S/MIME cryptographic signature ___ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: http://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
