Initiates a series of delegate messages (and general notifications) to determine whether modifications can be made to the characters and attributes of the receiver’s text.
- macOS 10.0+
The range of characters affected by the proposed change.
The characters that will replace those in
affected. If only text attributes are being changed,
true to allow the change,
false to prohibit it.
This method must be invoked at the start of any sequence of user-initiated editing changes. If your subclass of
NSText implements methods that modify the text, make sure to invoke this method to determine whether the change should be made. If the change is allowed, complete the change by invoking the
If you override this method, you must call
super at the beginning of the override.
If the receiver is not editable, this method automatically returns
false. This result prevents instances in which a text view could be changed by user actions even though it had been set to be non-editable.
In macOS 10.4 and later, if there are multiple selections, this method acts on the first selected subrange.