Add a when clause to the contributed explorer view such that it is only activated when the workspace has a pom.xml file

[tristan957]

Describe the bug
The extension contributes its view when not in a Maven project. Currently in a Python project without anything to do with Java and I see the view contribution.

To Reproduce
Steps to reproduce the behavior:

1. Open a non-java, non-maven project
2. See view is contributed

Expected behavior
Don't show view when not in a Maven project (no pom.xml).

Environments (please complete the following information as much as possible):

• OS: Windows 10
• VS Code version: 1.51
• Extension version: 0.25.0

Additional context
https://github.com/microsoft/vscode-maven/blob/master/package.json#L191
microsoft/vscode-java-test#793
microsoft/vscode-java-test#793 (comment)
microsoft/vscode-java-dependency#372

[tristan957]

Would it also be possible to add a name, contextualTitle, and icon? these would greatly benefit people who move the view into the Activity Bar like myself.

https://code.visualstudio.com/api/references/contribution-points#contributes.views

[Eskibear]

Don't show view when not in a Maven project (no pom.xml).

We used to do that, but later we decided to always show it. We received feedbacks from users (new to vscode) that they don't know how to start from scratch (e.g. create a maven project). The shortcut button (+) in the view proves to be helpful.
For the moment, you can right click and hide the view by your own.

But I do agree that if you are focusing on a non-java project(e.g. Python), it shouldn't bother you. My rough idea now is:

• if no folder/workspace is open, always show the view. So we can help those beginners start from scratch.

• if a non-java project is open (e.g. no pom.xml in workspace), we don't show the view, until you explicitly activate the extension. We should always provide users with an option to show the view if they want to. E.g. for users working on polyglot projects.

[tristan957]

Could there be a setting for advanced users such that we only see the view when a pom.xml exists? Or maybe just restrict to showing the view when there are java files in the workspace? Be less restrictive than looking explicitly for a pom.xml, which would maybe get the best of both worlds since users could create a maven project now that view is there, and advanced users wouldn't see it in non-java projects.

[tristan957]

@Eskibear if I want to also get #549 (comment) resolved, should I make a separate ticket?

Thanks for implementing at least the when clause! Very helpful!

[Eskibear]

I'm fixing it now.