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refactory-id / bootstrap-markdown

Bootstrap plugin for markdown editing
Apache License 2.0
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onChange is fired even while cursoring around in the textarea #274

Closed cgatesman closed 7 years ago

cgatesman commented 7 years ago

Cursoring around in a textarea should not be firing an onChange.

toopay commented 7 years ago

Afaik, It's inherit lower level library behavior. But i believe there is isDirty method somewhere, which can be useful in your callback

cgatesman commented 7 years ago

It seems pretty grossly inefficient. I can't rely on just a dirty flag. A user could type a character then delete that character. Now it's flagged as dirty, but the content has not changed. This means instead of a dirty flag, I have to string comparison the entire content on every onChange even though they may be just cursoring around in the text. If the text is extremely long, this could be very CPU intensive.

What is this "lower level library" you're referring to? It's just using a textarea. Seems like it is perhaps firing on keyup which is incorrect. It should just fire on input propertychange which I don't believe includes just cursoring around in the textarea.

toopay commented 7 years ago

What is this "lower level library" you're referring to?

The keyup and change, they are both inherited from jQuery.

It's just using a textarea. Seems like it is perhaps firing on keyup which is incorrect. It should just fire on input propertychange which I don't believe includes just cursoring around in the textarea.

This ought to be very simple. But unfortunately it isn't. keyup maybe a terrible event for input detection, you got the point. But Cut/Paste via contextmenu unfortunately is also input, and so is backspace.

I haven't test the performance comparison of using keyup against input or propertychange, but I'm sure we're looking at other issue here.