Preserve DragFloat from changing value when overlap

[JaroslavHolecek]

Version: 1.85
Branch: master

Is it possible somehow preserve (deactivate) DragFloat from changing its value (by dragging) in situation where DragFloat is overlapped by other widget (in my case Group ) and I drag this widget (Group)?

I simply want to move with Group in front (I make "node_editor" and Group is movable node ) and not change value of DragFloat in back.
Thank you.

I try to set AllowOverlap by #3909 (comment)
But this seem to work for two overalapped DragFloat -> I want to use it in case when DragFloat is overlapped by Group...

[ocornut]

Hello,

Your question is worded as too specifically (and maybe a XY Problem, this does not have much to do with DragFloat().

We can attempt to make AllowOverlap work with groups if it doesn't already, but please provide a minimum repro to first see if that is the case.

Otherwise you should use individual windows as a delimiter for hovering.

[JaroslavHolecek]

Thanks for fast response - Sorry for XY
Yes, generally should be enough to extend AllowOverlap to Group (or any Item that react to IsItemClicked/Hoovered etc.) (in sense that Group or other Item can be the overlapping one )
I will try to show some repo (tomorrow).

My node_editor is quite similar to https://github.com/thedmd/imgui-node-editor -> nodes are not window, but Groups of other elements -> than they can overlap -> when I grab and drag node (Group) I also fire changing value on underlying DragFloat - which I dont want.
And you are right, also I drag two overlapping nodes (Groups) when grab they on overlapping point - which I dont want too...

[JaroslavHolecek]

I am sorry for being late...

Repro code is:
`
static float value = 0;
static ImVec2 text_position = ImVec2(300, 100);
static bool moving_text = false;

ImGui::SetCursorPos(ImVec2(100, 100));
ImGui::PushItemWidth(50);
ImGui::DragFloat("df", &value);
ImGui::SetItemAllowOverlap();
ImGui::PopItemWidth();

ImGui::SetCursorPos(text_position);
ImGui::Text("This text is Group and drag flat is really DragFloat or Group - in my case. ");
if (ImGui::IsItemClicked(0)) { moving_text = true; }
if (ImGui::IsMouseReleased(0)) { moving_text = false; }

if (moving_text && ImGui::IsMouseDragging(0))
{
text_position.x += ImGui::GetMouseDragDelta(0).x;
ImGui::ResetMouseDragDelta(0);
}
`

If you move text over the DragFloat, release mouse and then drag text by some point that overlap with DragFloat -> you move with text and change value in DragFloat too... I do not want change value in DragFloat in this case.

In my real scenario are two cases:

1. DragFloat is really DragFloat and text is Group
2. DragFloat is Group and text is Group

[JaroslavHolecek]

@ocornut I am just not sure whether repro code ping you.

[ocornut]

Sorry this is too tricky and ambiguous to understand. This is not much a question about drag float.

I think maybe you should use BeginDisabled() or underlying ImGuiItemFlags_Disabled flag on the DragFloat simply.

[JaroslavHolecek]

OK, maybe more general issue is possibility of disabling interaction of lower item when two items overlap for "all item types" (as button behave).

When I want to use ImGuiItemFlags_Disabled, I have to compute whether or not Text overlap DragFloat (in my example) - which is not easy computation. And somewhere in Imgui this computation already run (for buttons at least)

[ocornut]

And somewhere in Imgui this computation already run (for buttons at least)

No computation is running. Hovering is given on a first-submitted first-served basis by default, and with AllowOverlap it allows override + checks the previous frame value (g.HoveredIdPreviousFrame).
If you use an item that had an identifier (e.g. InvisibleButton()) instead of Text() it'll have a chance to work.