Cursor position in relation to self.view

Question

There are many answers to get cursor CGPoint within UITextView. But I need to find a position of cursor in relation to self.view (or phone screen borders). Is there a way to do so in Objective-C?

Answer 1

UIView has a convert(_:to:) method that does exactly that. It converts coordinates from the receiver coordinate space to another view coordinate space.

Here is an example:

Objective-C

UITextView *textView = [[UITextView alloc] initWithFrame:CGRectZero];
UITextRange *selectedTextRange = textView.selectedTextRange;
if (selectedTextRange != nil)
{
    // `caretRect` is in the `textView` coordinate space.
    CGRect caretRect = [textView caretRectForPosition:selectedTextRange.end];

    // Convert `caretRect` in the main window coordinate space.
    // Passing `nil` for the view converts to window base coordinates.
    // Passing any `UIView` object converts to that view coordinate space.
    CGRect windowRect = [textView convertRect:caretRect toView:nil];
}
else {
    // No selection and no caret in UITextView.
}

Swift

let textView = UITextView()
if let selectedRange = textView.selectedTextRange
{
    // `caretRect` is in the `textView` coordinate space.
    let caretRect = textView.caretRect(for: selectedRange.end)

    // Convert `caretRect` in the main window coordinate space.
    // Passing `nil` for the view converts to window base coordinates.
    // Passing any `UIView` object converts to that view coordinate space.
    let windowRect = textView.convert(caretRect, to: nil)
}
else {
    // No selection and no caret in UITextView.
}