By default, the ToolTipX property is empty, which indicates that the tooltip is shown at its default position. The ToolTipX property indicates an expression that determines the horizontal-position of the tooltip, in screen coordinates. The expression supports predefined keys such as value, x, y, width and height among other general constants, operators and functions. The value indicates the current horizontal-position the tooltip is shown, in screen coordinates. The x, y indicates the horizontal/vertical position the tooltip is shown expressed in screen coordinates. The width an height keywords specifies the size of the tooltip is about to be shown. 

For instance:

• ToolTipX = "value + 16", indicates that the tooltip should be shown 16-pixels right to the default position
• ToolTipX = "128" specifies a fixed horizontal-position for the tooltip, no matter where the thumb is dragged
• ToolTipX = "1024 - width" shows the tooltip left to 1024 x-coordinate.

The ToolTipX property supports the following keywords:

• value keyword, specifies the x-position is screen coordinate, where the tooltip is currently displayed
• x keyword, specifies the x-position is screen coordinate, where the tooltip is currently displayed
• y keyword, specifies the y-position is screen coordinate, where the tooltip is currently displayed
• width keyword, specifies the width in pixels, the current tooltip is shown.
• height keyword, specifies the height in pixels, the current tooltip is shown.

Also, this property supports all constants, operators and functions defined here.