NativeScript TextField canPerformActionWithSender - nativescript

Question

I have a custom keyboard (made from buttons) in my app and I'm using it to populate a numeric value into a TextField. When a button is pressed, I set the text of the TextField while sanitizing the data — making sure there's only 1 decimal, no letters are entered, etc.
However, I'm now trying to detect when a user attempts to paste into the field so I can either prevent it entirely or sanitize the pasted text before allowing it to be pasted.
The approach I've taken so far is to try to implement the canPerformActionWithSender method on a NativeScript TextField.
I've tried the following (I'm using NativeScript Vue):
<TextField
ref="amount"
hint="$0.00"
#loaded="onTextFieldLoaded"
#unloaded="onTextFieldUnloaded" />
And...
onTextFieldLoaded(event) {
let textField = event.object
textField.focus()
nativeView.canPerformActionWithSender = (action, sender) => {
// `action` may be 'paste' so I can handle that action here
}
}
But this doesn't work. Is there an easy way to accomplish this without creating a custom component?

Answer 1

I was able to solve this with the following:
UITextField.prototype.canPerformActionWithSender = function (action, sender) {
return false;
}
This will disable the copy/paste/etc. menu completely. You can be more specific and check the action to only disable certain functionality if you like.
UITextField.prototype.canPerformActionWithSender = function (action, sender) {
if (action == 'paste:') {
return false;
}
return true;
}