I would like to convert my Swing application to Co...

# compose-desktop

[MatthiasMeger]

I would like to convert my Swing application to Compose. Therefore, I need multi-select support for a LazyColumn.
I have found some open source implementations, but none of them support multi-select with ctrl/shift key for selecting ranges of elements.
Is there anyone who has already implemented something like this?

[Lucas]

This looks similar to https://github.com/JetBrains/compose-multiplatform/issues/344, even if not a table
No specific solutions in here, just thought it was worth mentioning

[MatthiasMeger]

I added a PointerEvent to each item:

.onPointerEvent(PointerEventType.Press) { clicked(item, it) }

In "clicked" I check which mouse button was pressed and which keys (pointerEvent.keyboardModifiers.isCtrlPressed and pointerEvent.keyboardModifiers.isShiftPressed).

This way I fill a mutableStateListOf with all "selected" items.
I think the behavior is now like in my old Swing list (not easy to get all cases right with ctrl/shift 🤔!).

However, my items are wrapped in a ContextMenuArea to show a context menu for each item.
In Swing, right-clicking to open the context menu also selects an item (but only if it's not already selected, then ALL selected items remain selected).

My problem now is:
When the context menu opens, the PointerEvent.Press is fired so I can check if the clicked item needs to be selected.
However, if I right-click another item while the context menu is still open(!), then no PointerEvent.Press is fired?!

Any ideas how to get PointerEvents for right-clicking while the context menu is open?

By the way:
The documentation for the "onPointerEvent"-modifier says:
"_Note that this function is experimental, and can be replaced in the future by high-level functions"_
Is it known if there is a real plan to replace these features?

[MatthiasMeger]

Dima Avdeev answered a question from Hondogo Paul about pointer drag events.
The coding works in my case as well:

modifier = Modifier
             .pointerInput(Unit) {
                awaitPointerEventScope {
                    while (true) {
                        val pointerEvent = awaitPointerEvent()
                        val isMouseDown = pointerEvent.buttons.areAnyPressed
                        if(isMouseDown) {
                            println("click in pointer input modifier")
                            clicked(solution, pointerEvent)
                        }
                    }
                }
            }
    .onPointerEvent(PointerEventType.Press) { println("click in onPointerEvent") }

The text "click in pointer input modifier" is also printed when I right-click while a contextMenu is displayed. However, the text "click in onPointerEvent" is not displayed, so that pointer event isn't fired when a contextMenu is open and then another item is clicked.

So the solution for me is to use the ".pointerInput(Unit)" modifier to check for clicks while the contextMenu is open.