UMG - Drag&Drop capturing mouse events.

[Onoa]

Any chance that someone could post a small test level with this working so that we can study it and learn from it?

Thanks,

[ruohki]

I realized my stuff completely without that dragdropoperator stuff because of the fullscreenstuff

[Onoa]

Is it possible to center the dragged widget on the mouse cursor when using the DragDropOperation function (which seems to take the clicked position and uses it to move/drag the widget)?

I know it’s possible if the drag movement is calculated manually using the GetMousePositon and SetPosition functions for the widget, but I can’t find a way to make any position adjustments using the DragDropOperation function.

Is it possible? And if so, how?

Thanks,

[anonymous_user_a36a29c6]

This crashed for me on iOS IPhone 6 (works in mobile preview) when I create a Drag Drop Operation. Anyone else have this issue? (or not?)

[Desynchronous]

I noticed a problem I get with this when combining it with my UMG inventory, after having begun dragging a slot item(InventorySlot widget) it thinks it is still being hovered after moving the mouse and even dropping the widget in another slot which makes the style change from what I want (the “normal” style) to something “corrupt” on the widget I dragged from.
Anyone else experienced this and fixed it?

Kind Regards,
Bonny

[NickDarnell]

@Bonny;203345

I noticed a problem I get with this when combining it with my UMG inventory, after having begun dragging a slot item(InventorySlot widget) it thinks it is still being hovered after moving the mouse and even dropping the widget in another slot which makes the style change from what I want (the “normal” style) to something “corrupt” on the widget I dragged from.
Anyone else experienced this and fixed it?

Kind Regards,
Bonny

Yes, should be fixed in 4.7. We changed Slate to always fire a mouse leave when a drag operation begins to prevent those sorts of style hangups.

[Desynchronous]

@NickDarnell;203352

Yes, should be fixed in 4.7. We changed Slate to always fire a mouse leave when a drag operation begins to prevent those sorts of style hangups.

Great to hear !
Can’t wait for 4.7 to come out as full release

[xlar8or]

I’ve just tried 4.7 and the black squared alpha problem i mentioned earlier is still present, is there any workaround for that? Thank you

[NickDarnell]

@xlar8or;230178

I’ve just tried 4.7 and the black squared alpha problem i mentioned earlier is still present, is there any workaround for that? Thank you

Fixed in 4.8, the 4.7 system is still limited to drag drop only working in windowed mode games. The only work around is to implement your own drag/drop system moving everything yourself in another higher layer canvas/overlay.

[anonymous_user_01dd28a6]

I ran into the issue that the Drop event is on the receiving Widget, not the Wdiget being dragged. Once I got that it worked.

[Onoa]

@NickDarnell;166334

The documentation that exists is what’s above, official doc that covers all the things takes time and this feature still has some rough edges as noted at the top. “On Drag Over” is what is called on the widget that the droppable content is hovering on top of.

Hi,

Is there a way to know when a Drag Over is completed (e.g. Drag Over Leave function).

e.g.

Let’s say I want to highlight an icon with a color when hovering on top of it and dragging another icon. I can use the Drag Over function and change the color of the icon to red, but it seems that there’s no way to detect when the Drag Over is completed and hence let me change the color back to it’s default state.

Are these 2 functions what I am looking for, and if so, are you planning to expose them in Blueprint?

SWidget::OnDragEnter

SWidget::OnDragEnter

SWidget::OnDragLeave

SWidget::OnDragLeave

Thanks,

[Katianie]

Tried to implement this today and I’m running into the black square problem.

[war123]

Hey ,
The post is which version of the engine?
My engine is UE4.76,Can’t implement drag-and-drop in that way,what should I do?
please help me!

[Death_wyrm]

How would you do this with re-adding the dropped widget back to its parent, if the parent is a canvas panel?

[Slimbenneji]

hello eveyone can you help please

[Jezcentral]

@Slimbenneji;472818

hello eveyone can you help please

If you want some help, you’re going to have to give us a bit more info…

[Skinzart]

@Darnell;164942

Looks like my quick start guide for drag drop didn’t survive the drafting stage of the release notes, guess they were already getting a bit hefty - that’s right the release notes were bigger

NOTE: Drag/Drop bug, if you attempt to use it in a fullscreen game it’s going to kick you out. Currently it’s placing the content into a new temp window, on the list to be fixed. Other random stuff, if you attempt to make a button drag/droppable, you’re going to have a bad time. The button is going to capture the mouse on down and the drag will never occur. Also on the list of stuff to fix

Step 1) On Draggable Widget: You will implement the on mouse down event and do something like this: This allows drag detection to be detected, and will maintain it as long as the Drag Key is pressed.

Step 2) On Draggable Widget: When the drag is detected (after movement has overcome the jitter damping in Slate), On Drag Detected will be fired, and you can implement it like this, by creating a DragDropOperation that has a UObject Payload, and some widget representing the dragged content. Here’s an example I made with a spell icon widget.

Step 3) On Droppable Widget, you’ll need to implement some logic that does something with the Payload and Operation. I made a simple example that doesn’t do anything fancy it just moves the payload, which happens to be the spell Widget that the drag occurred on, and it just re-parents it to a widget it controls.

Step 4)
Click on [Root] in both the Draggable and Droppable widget’s, change their visibility to Visible, instead of Self Hit Test Invisible. That way they actually receive these mouse and drop/drag events.

I’ve tried make drag for mobile and i cannot implement that (touch release = Click) and if (touch move = drag). Do you have any suggestions?