Bug Report: Editor does not auto-scroll until manually scrolled to bottom once

[dipakluhar]

screen-20250905-163803.mp4

Environment

Library: react-native-pell-rich-editor (RichEditor + RichToolbar)

Platform: Android (reproduced on Android 13 / 14 / 15)

React Native version: [your RN version here]

Device/Emulator: [device/emulator details]

Current Behavior

• When typing inside the RichEditor, the cursor and text input area do not auto-scroll into view if the content grows beyond the visible area.
• Initially, when the editor is empty or only has a small amount of text, typing works fine.
• Once enough content is added to require scrolling, the cursor goes behind the keyboard or toolbar, and the editor does not auto-scroll.
• Auto-scroll only starts working after I manually scroll the editor all the way down once.
• After that first manual scroll, further typing scrolls correctly.

Expected Behavior

The editor should auto-scroll the cursor into view immediately, without requiring any manual scroll.
Typing in a new line at the bottom should always bring the cursor into view, even when the editor is freshly mounted.

Steps to Reproduce

• Mount RichEditor inside a scrollable container (ScrollView / KeyboardAvoidingView).
• Type enough lines so that the cursor moves below the visible area.
• Observe: The cursor goes under the keyboard, and the editor does not auto-scroll.
• Manually scroll the editor fully to the bottom once.
• Continue typing → Now auto-scroll works properly.

Analysis

The issue seems to be caused by the initial content height not being reported correctly from the WebView.

The onCursorPosition / scrollHeight is only calculated after a full manual scroll, which forces a reflow.

Until that happens, the editor’s height is stuck, and the auto-scroll logic does not trigger correctly.

Possible Fix

Trigger a scrollHeight recalculation after editor mount:

window.onload = function () {
setTimeout(() => Actions.UPDATE_HEIGHT(), 300);
};
editor.content.addEventListener("input", () => {
Actions.UPDATE_HEIGHT();
});

Improve Actions.UPDATE_HEIGHT() to calculate using Math.max(body.scrollHeight, docEle.scrollHeight, editor.content.scrollHeight) instead of relying on a single value.

Ensure OFFSET_HEIGHT is sent to React Native before the first manual scroll.