Create a tree that shows/hides node children on click:

Requirements:

• Only one event handler (use delegation)
• A click outside the node title (on an empty space) should not do anything.

باز کردن یک sandbox برای تمرین.

The solution has two parts.

1. Wrap every tree node title into <span>. Then we can CSS-style them on :hover and handle clicks exactly on text, because <span> width is exactly the text width (unlike without it).
2. Set a handler to the tree root node and handle clicks on that <span> titles.

باز کردن راه‌حل درون sandbox.