Mobile performance issues

[rask]

I'm implementing code-input on my personal website, inside an admin panel to write Markdown posts with.

On desktop it performs well, and is great to use. But on a mobile browser, it is literally unusable.

I have a regular text field above the code-input field, which can receive near instant character input if I keep fiddling randomly on the virtual mobile keyboard, typing in tons of characters per second. The code-input field on the other hand freezes for a second or two after each character typed in, and any characters typed during this period get discarded.

I'm running Firefox mobile with an up to date Android system on a new-ish XR21 Nokia phone. I'm not a mobile development expert so I can't even begin to think what might be causing this. I do understand that JavaScript powered text areas on steroids cannot compete with a plain input field in any way, but this does not seem like normal operation to me either.

Any ideas on how to start debugging this?

[WebCoder49]

Thank you for pointing this out, and sorry for the inconvenience - as this library builds on top of a textarea, it should work as well as a textarea on a mobile phone. I can reproduce your bug in Chrome on Android for code-input version 2.3, but not for 2.2.

I believe the bug is due to these lines of code, because these lines' functionality was first introduced in version 2.3, the first version of code-input in which this specific bug occurs:

code-input/code-input.js

Lines 526 to 532 in a404473

	// If editing here, scroll to the caret by focusing, though this shouldn't count as a focus event
	if(this.textareaElement === document.activeElement) {
	this.handleEventsFromTextarea = false;
	this.textareaElement.blur();
	this.textareaElement.focus();
	this.handleEventsFromTextarea = true;
	}

Short-term Workaround

You can downgrade to version 2.2.1 of code-input. There shouldn't be too noticeable a difference unless you use a screenreader / solely keyboard navigation, and no plugins should be lost.

Long term Solution

We need another way to scroll to the textarea's caret that doesn't temporarily blur the textarea, and/or remove this scrolling (Issue #93).

[rask]

Hey, downgrading to 2.2.1 fixed the performance issue. Many thanks! :)

I'll close this as you already seem to know what's up and have a separate issue for it. Let me know if you need more info so I can maybe try to find time to test things out.