Fired when a context menu is requested, carrying the relevant row index
(-1 if none) and the screen position to show the menu at. Raised both by a
mouse right-click (row under the cursor) and by the keyboard — the Apps key
or Shift+F10 — in which case the row is the selected one and the position is
anchored to it. The screen coordinates can be passed to showPopupMenu.
Fired when a context menu is requested, carrying the relevant row index (-1 if none) and the screen position to show the menu at. Raised both by a mouse right-click (row under the cursor) and by the keyboard — the Apps key or Shift+F10 — in which case the row is the selected one and the position is anchored to it. The screen coordinates can be passed to showPopupMenu.