What I'm trying to do is have a 3 state tree expansion.
I have three different icons for "expand" "collapse" "semi-expanded" which I want to use to show a partially populated tree control with all nodes initialized to semi-expanded state and then on clicking the "semi-expanded" icon it gets data from server and populates the tree and open that branch with "expanded" icon.
I tried looking for it but couldn't find anything close to it except the 3-state checkbox but don't know how to use it on 3 state icon when tree would only maintain 2 states.
Thanks in advance.
I think what you are looking for is called a lazy-loading tree. There are lots of examples your can google for, but here is a great example.
As far as the visual part of your request goes (3 different icons to show that state of the branch or node) - you could easily handle that with a custom renderer, by looking at a flag on the node for it's load status.
Does that help?
A 3-State tree control is a bit uncommon and might therefore be a bit confusing; consider that even simple 3-state checkboxes are relatively rare and users may not be accustomed to them. Maybe that's why you didn't find such a tree control.
Thus, maybe you should consider using an alternate design that doesn't require 3-state controls.
For example, the node could start in collapsed node. If the user expands it, and there is no data yet, show a single sub node with the text "retrieving data..." (and a progress wheel or other progress indicator, if you can) and start data retrieval. When the data arrives, replace this sub node with the actual data.
Related
My application is a tool library manager. It has a treeview containing a list of lists and tools. It also has a tableview showing a list of tools.
When I click on a list in the treeview, I want to show the tableview with the list of children. When I click on a single tool in the tree, I switch widgets and display the editform for the tool.
How do I limit the tableview to only the children of the selected node in the treeview?
My data model is a custom qAbstractItemModel.
I have a similar situation (not quite the same!) as yours. Before I share my experience, my assumption is that you have a database of sorts which consists of the items that make up your lists/tools.
One possible solution is to create two custom models, one for the tree view (say, MyTreeViewModel -> QAbstractItemModel, associated with QTreeView) and one for the table view (MyTableViewModel -> QAbstractItemModel, associated with QTableView).
The two custom models should be fed by the same agent working with the database. The key difference is that the tree view model works with the entire database, and the table view model with only a subset, that is, the children of the chosen item in the main list. Think of it as full mapping v. partial mapping of the database.
When the user clicks on the top list of nodes in the tree view, you can emit a signal which could be picked up by MyTableViewModel, populates with only the children, and is displayed by QTableView.
Because the same agent serves both models, you should be able to maintain data integrity, in the sense changes to the underlying data by one model should be reflected in the other model. This solution has worked out really well for my application. Hope this works for you too!
I'm not sure if this is a complete answer to my own question but I'm much closer. On the tableview I can call setRootIndex() and pass in the current item from the qTreeView. This works to show only the children of the current tree item in the table list.
For me, it still shows both tools and child lists, which I want to filter, but I think that's a different issue.
I have a problem I'm trying to solve and I'm really not sure I'm, A) solving it the correct way, and B) able to do what I want.
I have a List Page that is a basically a summary table (transportation table) that has a record in it for every Sales, Purchase, and Transfer order that we will ship. With it is a pile of rolled up information and such that's common from the 3 sources. We use this table on a few list pages and link out to where we need to. This was all built by someone else, but I'm maintaining some parts around it.
I've gotten a request to have the preview pane on a summary table based list page show the lines from the source order. So, if a "sales order" is selected in the grid, show the lines in the preview pane for the "sales order" that was selected. Same for a purchase order and transfer order.
So, my idea, based on pure ignorance and not a ton of experience with Dynamics is that I would just swap out the preview pane based on the source order. The SalesTableListPagePreviewPane for instance has already been updated to work with linking to this summary table. So, I wanted to just change the part reference at runtime.
I've managed to get the FormRun on a list page interaction class from the datasource. I've managed to get a list of the parts via the PartList object. But, I have no idea how to continue on to actually swap out a part reference.
Am I heading down the correct path? Is this a completely wrong Dynamics AX pattern?
Your assumption, that you can dynamically (run-time) change the parts of the form, is wrong.
Listpages especially are quite static, the only code available through interaction classes. It has the benefit that a listpage can be easily deployed on Sharepoint Enterprise Portal.
You have several options:
Use 3 different listpages for each type of transport
Use a common relation table with 3 sub-tables (sales, purchase and transfer)
The last option will enable you to do an outer join on the 3 sub-tables.
The common relation table could be a union view, but I doubt it will perform well.
I'm working on a Python+Gtk3 application with a fancy-looking GtkTreeView:
This is great for sighted users, but here's what Orca (the screen reader) says for a row in that tree view:
"Image, Devhelp, Collapsed, 9.2 MB"
A few problems, of course. First, it doesn't mention the checkbox for each row because I'm packing three cell renderers into a column. The three are available, but for some reason Orca doesn't mention the checkbox when it's buried that deep. Meanwhile, the image it mentions is the one on the far left, which is usually empty but sometimes a "restart required" indicator. Naturally, a blind user, much like a sighted user, couldn't care less that it is an image.
What I would like to do is to poke at the accessibility objects that describe this table in order to make them a little more helpful. Using Accerciser, I can see that these exist, but they all seem to be implemented with private, undocumented classes (like GtkTreeViewAccessible), and they don't look terribly extensible, but I'm hoping I'm wrong. Knowing that the treeview's accessible object is an AtkTable at some level, I did the following to set an accessible description for the image cell in the Backup row:
access = self.treeview_update.get_accessible()
cell_access = access.ref_at(0,0)
cell_access.set_image_description("Requires system restart")
(Orca still says "Image" after speaking the description, but I'll assume it knows what it's doing).
However, that code isn't very nice. When I call access.ref_at, I'm making particular assumptions about how GTK is mapping cell positions to rows and columns in the ATK object. I'm also limited to calling that when I first populate the tree, and I'm not sure if that is particularly sane.
So there's my problem: I would like to add accessible descriptions for my tree view cells in a nice way that won't break unexpectedly. How can I do that?
I am in the process of evaluating the ASP.NET Wizard Control. Where we need to collect data from different steps, validate data and towards the end I should be able to show a data summary.
I would like to know from the group if anyone has used this control and what issues they faced. Are there any usage limitations with this control?
The Wizard control can save you a lot of plumbing time if you use it well - however, learning to use it well may cost you more than the plumbing time that you save. If you plan to reuse it, then the initial investment in learning about its idiosyncracies may be worth it.
I have built a wizard in which the steps displayed in the side bar depend on which step you are at (and on what you have done to that point). It follows that the step you go to when you press Next or Previous is also determined dynamically.
To implement this, I read a lot of stuff about dynamically disabling steps, hiding steps, and adding and deleting steps. The latter led me into deep water with the ViewState. For what it is worth, here is my basic approach:
You can control which steps are visible in the sidebar by setting the step ID (and Title if set) to an empty string e.g. I have the step names in arrWizardSteps() and my steps defined as integer constants, then use
For i = intCREDENTIALS To intADDITIONAL_INFORMATION
Wizard1.WizardSteps(i).ID = IIf(Wizard1.ActiveStepIndex < i, "", arrWizardSteps(i))
Next
If the steps are relatively independent, you can handle the SideBarButtonClick, PreviousButtonClick and NextButtonClick events by calling the same routine, which you construct to handle leaving the current step, and entering the next, irrespective of which button you clicked to make the transition. For example, the routine might store the data captured by the controls of the current step, and load some data into the controls of the next step.
If you do handle these events, you probably need to handle changing the ActiveStepIndex yourself. The wizard will increment/decrement the ActiveStepIndex (depending on which button was pressed) if you don't change it (unless you set e.Cancel=true in your handler where e is the WizardNavigationEventArgs argument to the handler).
If your code for hiding steps needs to know the destination step then you need to put that code in PreRender, since at that point the wizard will have moved to the next step and you will know what it is.
Personally I don't like the wizard control. Its quite rigid and I didn't find it very nice to work with. Since then I have used the MultiView control inside and UpdatePanel with User controls in each View for each step for my wizards. This way it can be completely flexible.
With the MultiView approach you can also see all steps of the wizard easily in the designer.
This is just my option on the control though, I didnt give it much of a chance on its first visit.
I am trying to drag and drop hierarchical data in the same advanced data grid, and I would like the data provider to updated when the ADG is updated. (I want to be able to save and load this tree, so it is important that drags and drops are saved.)
I have a sample application (with view source enabled) posted here: www.crcarlson.com/adg/AdvancedDataGridDragAndDrop.swf
The sample app has an ADG showing hierarchical data as well as flat data. The first column of each datagrid shows the rowindex of the underlying data.
If you rearrange the items on the left ADG, the row indexes become unordered. If you click traceTree you see that the data provider is not in order.
On the other hand if you do the same on the right, the row numbers stay ordered even when the objects move around and if you click traceFlat, the data provider is in the order shown on ADG
My goal is to have the data provider order match the ADG order for the left grid which is displaying hierarchical data.
I would appreciate any advice on this, including "you can't get there from here, do it this way."
I noticed a few things while perusing your code and using the app:
Use an ArrayCollection instead of Array as the dataProvider for a view component whose data changes. This might solve your update problems.
If implementing an ArrayCollection doesn't completely solve your update problems, add the necessary logic to a dragDrop or dragComplete event handler.
I get a runtime error every time I drag an item from adg to adgFlat.
Here's Adobe's take on Using Drag and Drop. Specifically check out the last page titled "Moving and copying data". Good luck to you.