Understanding List View - Unreal Engine 5 Beginner tutorial 

Glad to hear it was of help. :)

lol yeah I was banging my head against this for 15-20 minutes and was like come on no way it's so complicated, I'll figure this out myself - NOPE no way lol. thanks for the great tut!

I am glad to hear that it works as a useful reference for reminders. :)

Glad to hear you found it useful!

You the best! For those that ran into the same thing; "is Variable" is at the top of the details panel to the right of the name of your list (listview_48 for example)

Thank you, appreciate that. :)

Thank you! Glad to hear it is proving useful to your project!

Cool stuff! My pleasure. :)

Glad to hear it, thank you. :)

Thank you! Glad to hear it. :)

You are very welcome!

I agree it might feel like it is a bit convoluted and complex for a list. There is some reason for that however because it allows the list to dynamically load in and out of memory as needed. :)

it's stupid complex, seriously, what happened to the usual array of data, and create a list item every n in a for loop

@@giampaolomannucci8281 You can still do that of course.

It's just a dynamic list. . . It's not that complicated. . .

​@@giampaolomannucci8281this is for scalability, it helps easily load this info when you have a full game with hundreds or thousands of assets. Saving memory and performance

Glad to hear it was helpful. :)

Glad to hear it!

Glad to hear you like it. Just a normal list is much easier than this. This should mainly be used for really large lists.

@@LeafBranchGames I started playing around with unreal a week ago and thought, making a working inventory seems like an achievable goal. Then I saw the tile option and then I found this video and thought ok, I'll try to get lists working. Now I'm stuck not being able to get the inventory array into the MainUI Widget because for some reason getting a variable from one blueprint to another with 'cast to' doesn't work without reference object (?) and I'm just...ugh, this isnt fun

@@michaelgreibich2078 A cast to is essentially just a check. You are checking if object X is of type Y. So, if the check succeeds, you can access methods and variables that exist on type Y. With that said, you should avoid casting as much as you can. You should use it deliberately under certain circumstances but most of the time people use them in costly or improper ways. My beginner tutorial for blueprint communication might be useful to you, also part 2 is useful: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-gXtZ-hmN8Js.html

Thanks for the help by the way. I managed to figure out that my mistake was pretty stupid and got over it, I have a new problem however. I got your example to work without problems, then I made a new project where I tried to do the same but instead of event construct I used a custom event to get an array from thirdperson to the MainUI, where I put it into a for each loop, to execute construct+init+AddItem with each array entry. Every time AddItem or any other function involving ListView is executed I get 'Blueprint Runtime Error: "Accessed None trying to read property ListView_0"'. I don't get why. I compared both projects and I can't figure out why one is working and the other isn't. The listview settings seem identical

@@michaelgreibich2078 An accessed none is a null reference issue. I explain the error here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-9PsoeBM82mk.html I would suggest debugging to see when and where this happens.

Thank you. :)

Better late than never. :)

I will add it to my todo list. :)

Thanks and please also a Search box. I cannot figure out how to filter by name or reference with 5000 items.

You are very welcome.

Sure, I can add it to my to do list.

Welcome to the channel! I am going to assume you are new to the channel since you make such unwarranted critique. This, because in this tutorial as well as most of my others, there is only ever one canvas panel, the one for the main widget. This for the reason you mention which I also inform about in many of my videos.

@@LeafBranchGames the problem is not to use a canvas.. The problem is who uses the canvas! There are so many beginners watching this and other tutorials.. And all use a canvas as basement (which is not neccessary.. Even as HUD root you can use Grid or Overlay).. And as Beginner you assume that you need to use a canvas for all widgets as root object... Which is absolute madness and bad design.. The problem in your tutorial here is just the sentence, to put a canvas as root to have something to drop other Elements on.. No more explanation or further infos about how to use a canvas correctly... And i deal with those beginners every f*** day... And i saw UMGs, littered with canvases and nested canvases and nested canvases in nested canvases that contain widgets with again canvases as root.. So.. Beginning UI tuts with a canvas as root.. Is bad practise in design.. And the root of the problem... Again.. The core of your tut is superb.. I learned well from it and understand. But you really should start different into...

@@blackdevilcreations Having a root canvas in your main or HUD umg is different from having it in every single widget or in even a majority of your widgets. Since I don't teach users to use canvas all the time, and even explain in many of my videos that they should not use canvas in every widget, then I am not the cause for those beginners using canvas panels. They have learned that behavior somewhere else.

Thank you. :)

Can you expand on what you mean here? As in you didn't use the Event On List Item Set at all? Or that you did use it and it was still not working? I'm having an issue myself where I do use that event and it does fire but it doesn't actually set anything when I use the set node. EDIT: Nevermind, using this doesn't call "event construct" so I just had to do all the other logic I usually do with event construct after the Event On List Item Set event. I guess they construct it then the other event fires.

Thanks for the feedback, I try to give variable names that are simple and descriptive. But as any programmer would tell you, naming things is one of the hardest things.

@@LeafBranchGames this was the best answer you could give. Lol. I struggle alot when naming my variables. I always have in mind that names have to make sense and tell what it is exactly even in six months when I forget what i did.

An object will be eligable for garbage collection when there is no longer any reference to it.

@@LeafBranchGames Allright 👍

My pleasure. :)

Sure, I will add it to my to do list.

Glad to hear you like it. Thank you for single-handedly trying to keep food on my table to watching it over and over. :) It may be an issue in 5.1. You could try using a different version to see if the issue persist.

Can you briefly explain how you were able to send info/calls back to the parent UI? Been trying this since last night but merely passing the parent via the object isn't working for me. You mentioned you used BP interfaces to send info back...which interface/func is that? Thx

:)

My pleasure. :)

My pleasure Andreas. :)

No problem.

Glad to hear you sorted it out! I am wondering though, are you having a lot of save games to list? Because you may just be better off with a simpler widget otherwise.

@@LeafBranchGames At the time, I was saving user-created levels, so each entry would have a screenshot of the map, and the data for it including the size (in map tiles), the name it was saved as, etc. It ended up working well, but I found myself coming back to this tutorial for a different game project lol

@@TheAxebeard Welcome back. :)

I am not familiar with the usage of tileview, so not entirely sure of how much of this logic applies to it.

@@LeafBranchGames Oh LOL, how did I not even notice THAT XD.....I thought I was using the same one as you ROFL. OK well I can tell you that it basically works the same, but for the CommonTileView (Part of Common UI) it seems to be broken or designed to be setup in a slightly different manner idk. Also they use the same Interface as well for the Entries I believe.

@@unrealdevop Makes sense that there is some functionality overlap.

They are just widgets, so it is normal UI functionality. I have plenty of tutorials on the subject, like this one: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-s-mtBIAVoeQ.html

Since that logic is all in the widget itself, that is a matter of simple UI logic. You just need to construct a widget that has the features and look you want.

Sure

What does the errors say?

Either hiding or collapsing is usually the normal way.

@@LeafBranchGames is that the same as clearing the list?

@@JuniusJakob No, those are not the same. Hiding or collapsing is a widget property.

@@LeafBranchGames Thanks for the info, I'll have to look into it more.

What do you mean?

@@LeafBranchGames I noticed when making my own changes to this system, that you're required to open and close the menu in order for the list to update if you pick something up. How would you update the list say if you moved an item from that list into a different slot? I've also noticed that only 2 items are allowed per list, but there doesn't seem to be a max you can set

The structure of the Tarray is the information you should be sending into your list array on a per list item basis just like in the tutorial. Happy new year to you as well!

​@@LeafBranchGames I got it worked out. It was silly, I was loading an early menu version. One should not code or script when tired!!! Excellent coverage on this and you have my sincere thanks!

@@HouseofGamersLive Glad to hear you worked it out. :)

You get a reference to the object in the listview and then you just change the value you want changed. Edit: Let me clarify. When you have the object reference by get item at, you have the object reference to the object which held the data. If you want to change data in the object it is the BP data object that needs the interface to change.

@@LeafBranchGames So if I have the struct that's referenced from on say, a character. I run the game in the editor, then go in and change the values of those structs in real time via the inspector, that won't update the HUD. If I want to update the HUD, I can only do that by changing the data on the data object I created?

@@ryanmcgechaen2103 I can't say for sure that it is the only way, it is a way. The documentation might reveal more functionality that is available to interface with, but I don't know of any at this moment of writing.

I will take your word for it. :)

I never encountered such an issue when working with it. If you are using Unreal engine 5.1, you could try and see if it happens in 5.0. 5.1 does have some issues.

Change the type from integer to name and then populate it as you want to add items to the list.

@@LeafBranchGames Sorry, I don't understand. What am I changing from integer to text?

@@DatCameraMON The index variable that you did not want to be an integer.

@@LeafBranchGames Ah, I see what you're saying. The issue is that I don't want to create a bunch of separate variables for each name, I'm trying to think of the scalability. That is why I was wondering about using an array of text with this, if possible but I'm running into some issues.

@@DatCameraMON Sure, an array of names makes sense for storing the information.

The purpose of the tutorial was to try and convey how list views work, hence the title, rather than a tutorial to achieve a certain specific list with an amount of functionality. The reason for this was that the tutorial sort of assumes a prerequisite amount of familiarity with widgets and UI functionality that I have taught in other videos. Sure, the video would have been more useful to you in this specific case if I made a whole list from start to finish. But you see, a lot of time goes into making tutorials, and it negatively affects views if I extend them to be super long. So instead of helping 95 people and 5 people being upset, like you, that it does not cover enough - RU-vid might instead show it to 10 people instead of 100, whom like you, who found it sufficient. That means that I was able to help 85 less people on this topic.

I don't mean to come across as combative and know that I think you produce good tutorials, I just don't understand the usefulness of a video on creating list views unless you show how to create a for-looped list to go inside of them. This is why it frustrated me, especially given the thumbnail which shows an inventory; something a beginner would not be able to make by following this video unless they learned separately or played around. To me, this is why there are two comments below asking about arrays (although in fairness one did solve the issue themselves). In terms of length, which I know nothing about, you could always do a two-part video series if you felt there was more worth covering on this topic. With that being said, do you have any tips on where I would plug my array into? This may help people who read this in the future. Mine is sitting in my Game Instance, but I'm not sure where to reference it. In truth, I may not be as sharp or talented as other viewers so that might be why I can't take the video and figure it out myself. However I'm hoping you can help give some pointers, and hopefully you don't take the criticism to heart.

@@kn_games I can put it on my to do list to make a follow up video on the topic. But I do this on my free time so I can not say when I will get the time to do it, especially with all the other requests and tutorials I have planned and in the works. As to a way forward from the situation you are in; You need to create an object, like in the video for each array item you have and populate the object with the information you want to pass along to the list view, then add that object to the list view like shown in the video. What information the object will contain and what information you will pass along when populating it, will depend on the array you have and what information you want to display. Use the example I showed with the text fields that are passed along as an example and replace them with the information you want to show.

Of course only do the video if you deem it necessary and can find the time, thanks for tips, really appreciate the stuff that's in the video and your help.

@@kn_games Time will always be the bottleneck. :) Good luck with your list, hope you can manage to add your array data into the list like you need to.

If you follow the tutorial closely, you should be able to recreate it.

I don't see why you would want an infinite inventory system, so it doesn't seem like the proper fit for that.

@@LeafBranchGames I don't mean an infinite inventory system, I just mean using a list view to display items in an inventory

@@robpenfold9500 A list view is meant to be used for very large amounts of items, an inventory tend to be much less in size.

@@LeafBranchGames So, say for example that I want the inventory to be dynamic in size - carrying a backpack adds an extra 20 slots in capacity. Would a list view not suite this?

@@robpenfold9500 It can be used for it, sure. But I would not use it for that scenario.

An object is an instance of a class. Do you plan to show something that is not an instance in a list?

@@LeafBranchGames yes, as mentioned all i want is some information displayed the might be saved in a class but i feels dumb to make an instance out of every researchable item.

@@pietpanzerpanzer5335 The content that is displayed and the widgets themselves, are two separate things.

@@LeafBranchGames ah but how do you set or pass a value like a class refrence into the list entry? Add item doesnt return the widget reffrences like create widget does?

@@pietpanzerpanzer5335 Just pass it along like any piece of information like shown in the tutorial.

It might seem a bit roundabout at first, but once you get the hang of it, it should not be too problematic. Although, a list view is an advanced view. For most cases a normal vertical box with widgets will do just fine.

Not sure what you are referring to as hacks. But yes, there is a cost to use list views if you are looking to benefits from its strengths over a normal widget panel. That is why you would build a framework to ease the use of a list view to suit the needs of the project it is to be used in.