// 1) Call BeginMultiSelect() with the last saved value of ->RangeSrc and its selection state.
// It is because you need to pass its selection state (and you own selection) that we don't store this value in Dear ImGui.
// (For the initial frame or when resetting your selection state: you may use the value for your first item or a "null" value that matches the type stored in your void*).
// 2) Honor Clear/SelectAll requests by updating your selection data. Only required if you are using a clipper in step 4: but you can use same code as step 6 anyway.
// 2) Honor Clear/SelectAll/SetRange requests by updating your selection data. (Only required if you are using a clipper in step 4: but you can use same code as step 6 anyway.)
// Loop
// 3) Set RangeSrcPassedBy=true if the RangeSrc item is part of the items clipped before the first submitted/visible item. [Only required if you are using a clipper in step 4]
// This is because for range-selection we need to know if we are currently "inside" or "outside" the range.
// If you are using integer indices everywhere, this is easy to compute: if (clipper.DisplayStart > (int)data->RangeSrc) { data->RangeSrcPassedBy = true; }
// 4) Submit your items with SetNextItemSelectionUserData() + Selectable()/TreeNode() calls.
// Call IsItemToggledSelection() to query if the selection state has been toggled, if you need the info immediately for your display (before EndMultiSelect()).
// When cannot return a "IsItemSelected()" value because we need to consider clipped/unprocessed items, this is why we return a "Toggle" event instead.
// When cannot provide a "IsItemSelected()" value because we need to consider clipped/unprocessed items, this is why we return a "Toggled" event instead.
// End
// 5) Call EndMultiSelect(). Save the value of ->RangeSrc for the next frame (you may convert the value in a format that is safe for persistance)
// 6) Honor Clear/SelectAll/SetRange requests by updating your selection data. Always process them in this order (as you will receive Clear+SetRange request simultaneously)
if(Shortcut(ImGuiKey_Escape))// FIXME-MULTISELECT: Only hog shortcut if selection is not null, meaning we need "has selection or "selection size" data here.
ocornut
1 year ago