Generate keyboard events for the frontmost application

cocoa, macos, objective-c

Solution

Sure, you'll want to use CGEventCreateKeyboardEvent to create keyboard events, then post them as such:

    CGEventRef keyup, keydown;
    keydown = CGEventCreateKeyboardEvent (NULL, (CGKeyCode)56, true);
    keyup = CGEventCreateKeyboardEvent (NULL, (CGKeyCode)56, false);

    CGEventPost(kCGHIDEventTap, keydown);
    CGEventPost(kCGHIDEventTap, keyup);
    CFRelease(keydown);
    CFRelease(keyup);

It's a bit more complicated than AppleScript but it does the trick. You do have to explicitly post a keydown and then a keyup event. More information at the Quartz Event Services Reference.

Problem

In Mac OS / Cocoa, may I synthesize keyboard entries - strings - for the frontmost application in a transparent way? To be more precise, I don't want to send special characters or control sequences. My only need is to send standard characters. Just learned here, that AppleScript can do the trick like this: ``` tell application "TextEdit" activate tell application "System Events" keystroke "f" using {command down} end tell end tell ``` Q: How would I do this using ObjC / cocoa? UPDATE 2012-02-18 - Nicks proposal enhanced Based on Nick's code below, here is the final solution: ``` // First, get the PSN of the currently front app ProcessSerialNumber psn; GetFrontProcess( &psn ); // make some key events CGEventRef keyup, keydown; keydown = CGEventCreateKeyboardEvent (NULL, (CGKeyCode)6, true); keyup = CGEventCreateKeyboardEvent (NULL, (CGKeyCode)6, false); // forward them to the frontmost app CGEventPostToPSN (&psn, keydown); CGEventPostToPSN (&psn, keyup); // and finally behave friendly CFRelease(keydown); CFRelease(keyup); ``` Using this method, a click on a button of a non-activating panel targets the event to the actual front application. Perfectly what I want to do.

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