How to insert text at cursor position of another application on Mac OSX Application (like OSK)?

Question

I'm trying to create an OSX application which would be a replica of On Screen keyboard. Is it possible to insert some text into the cursor position of another active application? Thanks in advance!

Answer 1

It is possible. Accessibility enables to change content of other applications, but your app can't be sandboxed and thus not available via AppStore.

CFTypeRef focusedUI;
AXUIElementCopyAttributeValue(AXUIElementCreateSystemWide(), kAXFocusedUIElementAttribute, &focusedUI);

if (focusedUI) {
    CFTypeRef textValue, textRange;
    // get text content and range
    AXUIElementCopyAttributeValue(focusedUI, kAXValueAttribute, &textValue);
    AXUIElementCopyAttributeValue(focusedUI, kAXSelectedTextRangeAttribute, &textRange);

    NSRange range;
    AXValueGetValue(textRange, kAXValueCFRangeType, &range);
    // replace current range with new text
    NSString *newTextValue = [(__bridge NSString *)textValue stringByReplacingCharactersInRange:range withString:newText];
    AXUIElementSetAttributeValue(focusedUI, kAXValueAttribute, (__bridge CFStringRef)newTextValue);
    // set cursor to correct position
    range.length = 0;
    range.location += text.length;
    AXValueRef valueRef = AXValueCreate(kAXValueCFRangeType, (const void *)&range);
    AXUIElementSetAttributeValue(focusedUI, kAXSelectedTextRangeAttribute, valueRef);

    CFRelease(textValue);
    CFRelease(textRange);
    CFRelease(focusedUI);
}

This code does not check for errors and makes assumption that focused element is text area.

Answer 2

Not sure if this helps, but in Applescript you can do something like

tell application "System Events"
    keystroke "Stuff here"
end tell

So maybe you can try call that within cocoa using NSApplescript or using NSTask and run

osascript -e 'tell application "System Events" to keystroke "Stuff here"'