KeysToShiftState function
Converts modifier keys in the LParam for a mouse message to a TShiftState value.
Declaration
function KeysToShiftState(Keys: PtrUInt): TShiftStateArguments
Keys | Pointer to an unsigned Integer with the mouse key states examined in the routine. |
Function result
Set type with the TShiftStateEnum values representing the specified Keys.
Description
KeysToShiftState returns a
TShiftState type with the
TShiftStateEnum values needed to represent the mouse key states in
the
Keys argument. KeysToShiftState
ANDs the value in Keys
with RTL mouse key constants to determine the values in the set, including:
- MK_Shift
- Includes ssShift for a non-zero result.
- MK_Control
- Includes ssCtrl for a non-zero result.
- MK_LButton
- Includes ssLeft for a non-zero result.
- MK_RButton
- Includes ssRight for a non-zero result.
- MK_MButton
- Includes ssMiddle for a non-zero result.
- MK_XBUTTON1
- Includes ssExtra1 for a non-zero result.
- MK_XBUTTON2
- Includes ssExtra2 for a non-zero result.
- MK_DOUBLECLICK
- Includes ssDouble for a non-zero result.
- MK_TRIPLECLICK
- Includes ssTriple for a non-zero result.
- MK_QUADCLICK
- Includes ssQuad for a non-zero result.
GetKeyState is also called, and the following virtual key codes are processed for the return value:
- VK_MENU
- Includes ssAlt when the result is a negative number.
- VK_LWIN, VK_RWIN
- Includes ssMeta when the result is a negative number.
KeysToShiftState is used to translate the key values for mouse messages in methods like DoMouseDown, DoMouseUp, and WMMouseMove in TControl.
See also
An experiment, built from development snapshots. Not the official Free Pascal or Lazarus documentation.