Multi select treeview that supports drag of multiple Items in WPF - wpf

I was searching for possible solution for hours and could not find any.
Hopefully someone can help me.
I managed to implement Multi Select WPF TreeView using the following answer: https://stackoverflow.com/a/6681993/1679059
It works nicely but I want to be able to drag selected items and drop them into the DataGrid.
In PreviewMouseMove event handler previously selected items get deselected so I can't prevent that from happening.
I was trying to prevent deselecting items in PreviewMouseLeftButtonDown event handler but at that point I cannot know if a user intends to select an item or drag selected items.
Can someone help me with that problem?

you can do this by adding a bool variable let say 'isLeftClick' in MouseLeftButton Event change isLeftClick to 'TRUE' and in MouseMove event check if isLeftClick is true or false if it is true then user thn user is trying to drag.
also check if mouse is pointed on one of selected nodes thn drag those nodes if it is on some unselected node then select that node and drag it.

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React elements that are selectable and draggable

I'm using react-selectable-fast on a list of items that can be selected. However an item or a group of selected items should also be draggable, which is implemented using react-dnd.
The issue is that the selecting comes in the way of dragging; when hovering on top of an item and trying to drag it I end up selecting instead.
I've managed to fix the issue with a hack: store in state whether currently hovering an item or a group of selected items and if so disable the <SelectableGroup>. However this means that the whole list of items is rerendered every time I move the mouse over an item.
So I would like a better solution but I haven't been able to find one. In the last attempt I put the draggable element (using connectDragSource) on top of the selectable element (using createSelectable) again on top of <SelectableGroup /> and gave them increasing z-indexes, also tried playing around with stopPropagation() and preventDefault() but still the selecting overrides the dragging.
Any ideas?

Where is the Visual Basic 6 Combo Box Click Event?

I'm new to Visual Basic, I have scoured the net to look for the event handler for the combo box click event but I cannot locate it. I am trying to make an event happens if a certain index is selected with the combo box1 then another combo box2 will populate the selected the index.
i have looked at links like these but it does not explain how or what the person did to access the _ click event VB6 Combo box events
In the code window for the form, select the desired control from the left drop down, then the event you want from the list of all events in the right drop down:
It will create the procedure for you and make it the active one. This is the same as VB.NET assuming you have the selectors on.
I haven't been using VB6 for ages, but i think what you need is covered here: http://www.vb6.us/tutorials/visual-basic-combo-box-tutorial
I cannot recall having to do anything special when using click events in VB6 at all.
In the first combobox click event, you should be able to have an if statement checking if a certain item is selected using .ListIndex and if so, populate the other.

key board event on dropdown combobox mfc

How to handle delete key on dropdown of combobox which is created with style CBS_DROPDOWNLIST?
I want to delete the items in the dropdow list when user presses delete key. Please someone explain how to handle this on a combobox.
Either use PreTranslateMessage in the parent dialog to fetch the VK_DELETE key. Or subclass the list control when the combo box drops down.
You can get the handle of the list control with GetComboBoxInfo

Prevent Treeview Selection in Silverlight

I have two panes in my page (category and items). The category pane is basically a n-level tree view which controls what items are to be shown on the items pane on the right. So if I choose a category, the items panel on the right hand side will show all items in that particular category (in a datagrid). I am fetching the items from a WCF service in the SelectedItemChanged event.
Now the items grid in the right pane is an editable datagrid. So when a user has some unsaved changes in the grid and tries to change the category, I need to give him a warning message (message box with Ok/Cancel) and on cancel click, I need to suppress this category selection change.
Now, I have tried the the MouseLeftButtonDown event to suppress this, but it somehow doesn't seem to work.
I have refereed this link for the possible solutions.
Can anyone please suggest something?
At the end of your selectedItemChanged event, call [yourTreeView].ClearSelection()
This will give the appearance of the treeview not performing a selection, yet will react as a click.

Problem with combobox dropdown

I have a problem regarding combobox dropdown. Once a dropdown is opened, if I want to move focus to other control (say a textbox), I need to click twice because on first click, the combo dropdown is closed and then on second click, the textbox gets focus. How should I fix this? Please help.
You could listen to the DropDownList.SelectedIndexChanged event, and in the event handler set focus to the next control, either by setting TextBox.Focus(), or by calling System.Windows.Forms.Control.SelectNextControl()
I think this would be 'non standard' behaviour for what its worth. Its quite normal to expect the user to tab or select the next control after using a drop down.
Edit: Sorry, in a WPF ComboBox the equivalent event is SelectionChanged, but on reflection you'd be better using OnDropDownClosed. This would mean you only move the focus specifically after using the drop down rather than just whenever the value changes.

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