Prevent creating undefined 'layers-sub-list' when the consecutive layer is not a group

[crisner]

Hi, this is a first-timers-only issue. This means we've worked to make it more legible to folks who either haven't contributed to our codebase before, or even folks who haven't contributed to open source before.

If that's you, we're interested in helping you take the first step and can answer questions and help you out as you do. Note that we're especially interested in contributions from people from groups underrepresented in free and open source software!

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If you have contributed before, consider leaving this one for someone new, and looking through our general help wanted issues. Thanks!

🤔 What you will need to know.

Nothing. This issue is meant to welcome you to Open Source :) We are happy to walk you through the process.

📋 Step by Step

• 🙋 Claim this issue: Comment below. If someone else has claimed it, ask if they've opened a pull request already and if they're stuck -- maybe you can help them solve a problem or move it along!

• 📝 Update the file layersBrowser.js in the leaflet-environmental-layers repository.

See this page for some help in taking your first steps!

Problem

We are creating elements with an id of undefined.

Solution

This section:

leaflet-environmental-layers/src/util/layersBrowser.js

Lines 155 to 164 in 71e434e

	if(group !== obj.group) {
	this._createGroup(obj);
	groupHolder = this._createGroupHolder(obj);
	};
	if(obj.group) {
	groupHolder.appendChild(this._addItem(obj));
	} else {
	this._addItem(obj);
	}

should look this after changes:

      if(obj.group && group !== obj.group) {
        this._createGroup(obj);
        groupHolder = this._createGroupHolder(obj);
      };

      if(groupHolder && obj.group) {
        groupHolder.appendChild(this._addItem(obj));
      } else {
        this._addItem(obj);
      }

The only changes that need to be done are on lines 155 and 160.
This line:

leaflet-environmental-layers/src/util/layersBrowser.js

Line 155 in 71e434e

if(group !== obj.group) {

to this:
if(obj.group && group !== obj.group) {

and this line:

leaflet-environmental-layers/src/util/layersBrowser.js

Line 160 in 71e434e

if(obj.group) {

to this:
if(groupHolder && obj.group) {

• 💾 Commit your changes

• 🔀 Start a Pull Request. There are two ways how you can start a pull request:

1. If you are familiar with the terminal or would like to learn it, here is a great tutorial on how to send a pull request using the terminal.

2. You can also edit files directly in your browser and open a pull request from there.

• 🏁 Done Ask in comments for a review :)

Please keep us updated

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🤔❓ Questions?

Leave a comment below!

[llabake]

Hi, I would like to claim this.

[crisner]

Sure, go ahead! 😃