tried all the methods mention in React-beautiful-dnd lib to make work with virtual list but can't make it work with React-virtualized-table.
Related
As the document said, TreeView in GTK4 has been deprecated since 4.10. The recommended replacement for it is ColumnView. However, I can't find clear documentation or example about how to build a treeView-like widget in GTK4 by ColumnView.
I found maybe TreeExpander related to it but I still don't know how to deal with it.
A very brief outline of what I did:
Familiarize yourself with how the new dynamic list widgets (Gtk.GridView and Gtk.ColumnView) work for a flat model (GLib.ListStore). There is example code in the Demo app.
Create a Gtk.TreeListModelCreateModelFunc function that takes a model item as a parameter and, if that item has children (e.g. is a folder in a filesystem model), creates and returns a Gtk.ListStore to hold the children. If the child items are already available then they can also be appended to the child model here. This means the child items are preloaded whether or not the row is expanded. For startup performance reasons, you might want to arrange to load them when the row is actually expanded which is more difficult - in this case you have to add a dummy child to the model else the expander will not be displayed.
Create a Gtk.SignalListItemFactory.
In the setup handler, create a display widget as usual then instead of using your display widget as child of the Gtk.ListItem, you create a Gtk.TreeExpander, and make that the child the Gtk.ListItem and make the display widget a child of the expander.
In the bind handler, get the display widget and model item from the supplied object. A complication here is that the object may be a Gtk.TreeListRow whose item might be another Gtk.TreeListRow so getting to the model item is harder. Bind the widget to the model item as usual. Then get the Gtk.TreeListRow from the Gtk.ListItem position and set the expander's list-row property to it.
If you delayed loading the child items then you would need to detect when the row is first expanded. You can connect to the notify signal for the Gtk.TreeListRow.expanded property to do this.
Use a Gtk.TreeListModel with a GLib.ListStore as its root_store as the model of a Gtk.ColumnView (after wrapping in Gtk.SelectionModel as usual). You must set the passthrough property to false else no expanders appear. If you are loading child items on demand then autoexpand should also be false.
If you are using a Gtk.ColumnView with multiple columns, you only need add the expander to the first column. Otherwise the factory signal handlers or similar to the flat model except the bind handler needs to be adapted for Gtk.TreeListRow parameter.
Simplifications and performance improvements may well be possible or later versions of Gtk4 may introduce some conveniences to make it less fiddly.
I am working on a file browser implementation using the above strategy, currently at https://github.com/elementary/files/tree/gtk4-treelistmodel but this may be merged into other branches (or abandoned!). Note that this branch is under development and contains unresolved bugs but the display of items works.
I have a list of widgets which needs to be sorted. I want to create a container for these list of widgets to re-sort them each time new widget is added. How can I do it?
I can see the following ways:
a straightforward way is place them into arraylist and sort via Comparator, but after a new element is added we have to remove all list from container and add them again, in a new order.
use some sorting container. i have found only CellTable for this. But actually I dont need its rich functionality - I have only one column, dont need to sort on user events, only when new element added or removed, - so is there something else I can utilize in my use case?
GWT 2.4
PS
Actually, I am looking for something, that can be expressed like "widget container backed by widget collection", i.e. I change collection - container changes its contents, how can I implement this, or where can I find it?
PPS
The widgets can be different, thats why I dont think I can use CellTable easily.
There is no straightforward way of re-sorting the elements in the DOM after you add a new widget.
When the widgets are attached you cannot just move them (change their position in the document structure) without detaching and re-attaching.
Well, with absolute positioning you can just change the left-top coordinates to move the items, if it is what you need.
I had a similar problem to solve when I had to sort TreeItem elements (no built-in sort method available). As a workaround, I read all the children into the list and remove them from the parent widget at the same time, then sort these items using Comparator and add them back to parent from the sorted list. Everything is in a single sort() method, which encapsulates all required functionality and kind of simplifies understanding of this code.
"widget container backed by widget collection"
I would like to learn about one like that that also can do sorting and re-attaching on the fly. But it still will be backed by the same detaching-attaching I assume. I would recommend you to write one yourself, that will fit your particular needs. Either you need a Tree or a FlowPanel or anything else - you can extend that and add sort() logic according to context. And override add() method accordingly. So, your first option looks like a possible solution to me.
here's my problem, I'm using mootools' Drag&Drop functionalities, it works great but i can't find a way to add new droppable element on the fly since the droppable element are defined when the draggables are.
Their is a method makedraggable that you can use to add draggable element but it has no equivalent for the droppables.
With jQuery, you set the draggable elements on one side and the droppable on the other, so you can do pretty much what you want.
Do you know a way to solve my problem?
in theory, you should be able to push elements to the instance.droppables collection.
var foo = new Drag.Move({
droppables: document.getElements('div.dropHere'),
...
});
foo.droppables.push(document.id('newDropHere'));
// or...
foo.droppables.include(element); // etc. all array/Elements methods.
read https://github.com/mootools/mootools-more/blob/master/Source/Drag/Drag.Move.js
if you want actual help, build an example on tinker.io or jsfiddle.net. if memory serves, this has been asked here before and there had to be some extra work around parsing possible droppables in addition to adding to the Collection.
I know that the eclipse code completion widget can be customized to add new suggestions and even to change the order.
I'm wondering whether there's a way to replace the current list format (or single-level tree, if this is a tree control) with a tree of multiple levels.
Thus, for example, instead of selecting from a list of methods sorted by name, I will select from a category and then from a subcategory, and then from the items.
I'm not too familiar with that part of the SDK, but I'd like to know if this is feasible.
Thanks!
In Eclipse, I am using a TreeViewer to show a custom tree, whose contents are drawn from an ITreeContentProvider. Now I am trying to create a second view that allows me to automatically show a two-way comparisons of two such trees. I found various views for textual comparison within Eclipse, but I could not find an easy way to show the structural differences between two arbitrary trees. Any thoughts?
When the Data Model the ContentProvider is creating and the labelProvider is diplaying is the Same, you could use the same viewer in the right and the left of a view.
You could than compare the TreeItem Elements of both TreeViewer and mark the ones, which has changed.
The other solution is to compare the DataModels and add a special flag to the changed elements. The LabelProvider can check this flag and draw a special color to indicate, that this element is different.
I do not know an Editor inside Eclipse, providing this functionality.