"Paste" Text to External Mac App First Responder

Question

Is there any (App Store safe) way of automatically filling another app's first responder text field with text? For example, using a hot-key specified by an NSStatusBar application, a user highlights text in a separate app, like TextEdit, and pastes new text into TextEdit that the status bar app has generated based on situational data.

Answer 1

Is there any way of automatically filling another app's first responder text field with text?

Yes, checkout the following AppleScript:

tell application "System Events" to keystroke "Hello World"

Use NSTask to run from Objective-C:

NSString *theText = @"Hello World";
NSString *theSource = [NSString stringWithFormat:@"tell application \"System Events\" to keystroke \"%@\"",theText];
NSAppleScript *theScript = [[NSAppleScript alloc] initWithSource:theSource]; 
[theScript executeAndReturnError:nil];

Note that the script requires access for assistive devices:

System Preferences → Universal Acces → Enable access for assistive devices

Applications using the code above won't rejected by Apple.