Hierarchical Data, Recursion, Tree-Views, and a Custom Class to Assist

[MajP]

Here is an 80% solution on the Access Item Genie. I will keep adding to this. There is little error checking so it may crash. Also some of the right click menu is not complete (Edit a node, node information, and delete a node are not coded). But most of the basic functionality is there.

Features
-Right click to add Locations or Items
-Can add under an existing node or as a root node
-Click on a location and it shows all items in that location in the subform
-Click on an item and it brings up item details
-Full drag and drop to move locations and items under another location
-Can edit the location name directly in the tree (little finicky you have to click then wait)
-Can edit items or locations by the subforms and will reflect in the tree. Include moving location

If you want to collaborate on this I think it could be a very workable idea. We could start a new thread and continue to add features.

Other features to add.
1. Bulk location adding
2.Bult item adding
3. Provide Location summary information. Could total all items, cost, in a location and all sub locations.
4. reporting
5. Duplicate the right click features to a menu or buttons
6. Aesthetics.

You will need to reselect all of the images will will save the correct path. I will fix that in the future to only save the file name and then you only have to pic the path once.

 

[Mike Krailo]

That confirms I was on the right track with this. It's getting late so I'll work with it more tomorrow morning.

 

[MsAccessNL]

Nice work! Would be great for a bom inventory system.

 

[MajP]

@MsAccessNL,
I built a BOM demo that I thought was very useable for what the OP asked.

Looking for some direction.

I am realizing that the Tree View works well for navigation, but would not be our preferred method for input/queries. Too many mouse clicks. That depends on your data. I can demo some structures that adding a node and moving a node would be way faster then any other method. Treeviews work well...

www.access-programmers.co.uk

However, the OP never responded and no one really seemed interested. It is something I think I would have actually used in a previous job. This allows you to pick generic parts assign to a specific assembly and then make the "as built" list by adding actual part serial numbers.

If interested here it is
In the same video look at 24 minutes in to see how it works.

Access Europe - Wed 7 Aug: Using Treeviews with Access Applications (Pete Poppe)

The next Access Europe User Group meeting will be on Wednesday 7 Aug 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM). In this session, we are pleased to welcome Pete Poppe who is very well known to Access World Forum members as MajP In this session, Pete will...

www.access-programmers.co.uk

Here is the original thread

Looking for some direction.

I am realizing that the Tree View works well for navigation, but would not be our preferred method for input/queries. Too many mouse clicks. That depends on your data. I can demo some structures that adding a node and moving a node would be way faster then any other method. Treeviews work well...

www.access-programmers.co.uk

This thread discusses more my table structure for a BOM and my different opinion of how you can structure it.

Solved - Products - Sub Assemblies - Assemblies

Its been a while but I wrote a system many years ago - we used the same principle as outlined by arnel

www.access-programmers.co.uk

 

[Mike Krailo]

Those location icons are hard to work with. I attempted to use some png's converted to bmp's and the transparancy is lost! So the icons have to be set in stone with a particular background. At least I understand how the images are getting assigned the key value now. It is simply the name of the file itself. I didn't catch that the first time looking at it. Anyway, I'm working on additional icons and created a cool genie logo for the form. I added one more field for item details called ItemValue to show the actual value of the item since my truck is no longer worth anything near what i paid for it. So the icons in this version are messed up because of the conversion failure to bmp. What would be nice is to capture all the icons in the folder in the dropdown on the form.

 

[MajP]

What would be nice is to capture all the icons in the folder in the dropdown on the form.

Currently I list these manually in a table. This could be automated and show the actual icon. Now when you add a location you choose the name of the icon, but do not get to see it. This could be a pop up subform with the Icon name and image where you pick the icon type for the image. The code to do this already exists because it loads the image list with all the icons at runtime. This could also be modified to load the table with the icon names and paths at runtime. Then you could have a pull down showing the icons. I am slowly adding a lot more features and will repost later.

 

[Pat Hartman]

I built a BOM demo that I thought was very useable for what the OP asked.

I liked it This one is more generally useful though since BOM processing is less common than inventory processing.

 

[Mike Krailo]

There are really not many typical root locations in a given household, but I guess for other applications this would be nice. I did discover your table of icons, and then it was a simple matter of updating the icon list. So a simple Edit List Form should do the trick.

I'm still working on getting a few more icons in the list. The last conversions were too small, I should have gone with 255x255. How do you manipulate the text size in the tree? It's just too small of a font for me.

 

[MajP]

I am going to make a dedicated thread to this and we can continue to demo features. I already made quite a few updates. I demo where you can can do all the formatting. For now I updated it to 11. But you can color and modify the font. Could have different colors for locations and items.

 

[MajP]

New Access Item Genie thread with updated features.

Access Item Genie demo for Organizing / Tracking your Items

This demo was asked by @Mike Krailo if using an Acess Treeview could you do some of the functions of the Utility https://itemgenie.com/ He and I have been working together to make this a useable utility and demonstrate a lot of functionality using a Treeview. Some background here...

www.access-programmers.co.uk

 

[LucasGills69]

Great work you've done here man.

I'm a fan of the Treeview control myself and use it as soon as info has to be displayed in hierarchical manner. The users love it as well because it allows to perform a lot of different actions in a very simple and graphical way.

One thing I'm looking for is the ability to move items between nodes using drag & drop, that is to modify the sort order within the same parent node. I know how to change the parent node using drag & drop but I'd like to offer both functionnalities.

Windows applications generaly do this by displaying a thin line between the nodes when you're dragging over.

Did anyone here already succeed with this ?

 

[MajP]

It is demoed in the Item Genie and in the E2E demo. See post #181.

There are methods in the class to move up and down within a node. The arrow keys on the right are faster to move things up and down because you can just keep clicking them without right clicking the pop up menu.

However, I may need to rethink how I was doing it. I thought my original method would be faster, but it may be slower.

When I move the nodes, I am really swapping the display text, and keys between two nodes. The nodes themselves really are not moving.
It may be faster to actually delete the node and readd the node at the correct location.
When you add a node you can add as a root, add to a parent, or add to a sibling. If you add it to a sibling then it should add below it.

 

[LucasGills69]

Thanks for the quick answer.

Yes I saw you were using up and down command buttons (I usually offer them as well) in addition to a contextual menu.

What I'm looking for is a way to provide both dropping the selected node on another node (=make the selected node a child of the target node) and dropping the selected node between two nodes (=make the selected node a sibling of the target nodes and place it between them).

This would certainly involve a two states cursor (move inside / move between) to help the user make the correct choice.

 

[MajP]

What I'm looking for is a way to provide both dropping the selected node on another node (=make the selected node a child of the target node) and dropping the selected node between two nodes (=make the selected node a sibling of the target nodes and place it between them

You cannot drop "between". If you drop off of the nodes it will assume you want to add as a root node. You cannot stop or alter where it drops, but you can reverse it after the fact.

Now I do have code in the item genie demoed where if items are dropped on another item (make no sense) will move it to the parent location of the item dropped on. You cannot stop it from adding as a child but you can move to the correct place after dropping.
You can implement something like this where you move to the correct position after the drop, but this seems like a worse UI then the move up move down, which is my opinion is far better than drag drop because of some of the limitations of dd (see below).
The problem is how to tell it to add as child or move to new location. You could prompt after you drop "Do you want to add as child, or move to new location". If add as child you do nothing, if move you add as sibling. But that seems obnoxious, if you only move some of the time.

Or you could have a "State" button. "Set Sort by Drag Drop", "Set add Child by Drag Drop".
In the prior you do what I said when you drop, you then move to correct position.
If the latter you do nothing in addition.

But bottom line you would need some of way to tell it to either add as child (do nothing), or move / sort and then put it in the correct position.

In some trees this may work and you do not have to prompt or set the state.
But if you had defined levels (Employees, orders, order items) then you can assume that anything dropped in the same level is meant to be sorted and not added as a child.
For example the item genie you cannot add an item as a child to an item so you could check that and assume to move it automatically every time.
But locations can have sub locations and more likely you are adding as a child vice sorting.

FYI, Drag and drop is pretty useless and I have gone away from that. It only works in very small trees that fit in the window. There is no autoscrolling as far as I know. So if you want to drag beyond the visible window you cannot. I now use a feature that will show check boxes of what you want to move then you can scroll anywhere in the tree (very large trees) and double click to move.

 

[LucasGills69]

You cannot drop "between". If you drop off of the nodes it will assume you want to add as a root node. You cannot stop or alter where it drops, but you can reverse it after the fact.

Now I do have code in the item genie demoed where if items are dropped on another item (make no sense) will move it to the parent location of the item dropped on. You cannot stop it from adding as a child but you can move to the correct place after dropping.
You can implement something like this where you move to the correct position after the drop, but this seems like a worse UI then the move up move down, which is my opinion is far better than drag drop because of some of the limitations of dd (see below).
The problem is how to tell it to add as child or move to new location. You could prompt after you drop "Do you want to add as child, or move to new location". If add as child you do nothing, if move you add as sibling. But that seems obnoxious, if you only move some of the time.

Or you could have a "State" button. "Set Sort by Drag Drop", "Set add Child by Drag Drop".
In the prior you do what I said when you drop, you then move to correct position.
If the latter you do nothing in addition.

But bottom line you would need some of way to tell it to either add as child (do nothing), or move / sort and then put it in the correct position.

In some trees this may work and you do not have to prompt or set the state.
But if you had defined levels (Employees, orders, order items) then you can assume that anything dropped in the same level is meant to be sorted and not added as a child.
For example the item genie you cannot add an item as a child to an item so you could check that and assume to move it automatically every time.
But locations can have sub locations and more likely you are adding as a child vice sorting.

FYI, Drag and drop is pretty useless and I have gone away from that. It only works in very small trees that fit in the window. There is no autoscrolling as far as I know. So if you want to drag beyond the visible window you cannot. I now use a feature that will show check boxes of what you want to move then you can scroll anywhere in the tree (very large trees) and double click to move.

Again thanks for the detailed answer.

No easy way to do this, then.

I'm currently checking a few options, I'll tell you if I come up with something.

By the way you can solve the missing auto-scrolling using EnsureVisible on the target node's parent or next node.

 

[MajP]

EnsureVisible on the target node's parent or next node.

Sounds like a game-changer, but how do you assign to the target if you cannot scroll to it?

 

[LucasGills69]

Sounds like a game-changer, but how do you assign to the target if you cannot scroll to it?

If you're dragging up to the TW border, the target becomes the first visible item at the top.

If you're dragging down to the TW border, the target becomes the last visible item at the bottom.

By ensuring that the top item's parent node or the bottom item's next node is visible, it actually auto-scrolls.

 

[LucasGills69]

Not sure if I was clear enough...

English is not my mother tongue