GetThemeTrackThumbPositionFromRegion

GetThemeTrackThumbPositionFromRegion
Header:	Appearance.h		Carbon status:	Supported

Obtains the relative position of a track’s indicator, given its current position.

OSStatus GetThemeTrackThumbPositionFromRegion (
    const ThemeTrackDrawInfo *drawInfo, 
     thumbRgn, 
    SInt32 *relativePosition
);

drawInfo: A pointer to a structure of type ThemeTrackDrawInfo. Before calling GetThemeTrackThumbPositionFromRegion, set the structure to contain the current visual characteristics of the track.
thumbRgn: A value of type RgnHandle. Before calling GetThemeTrackThumbPositionFromRegion set the region to contain the actual dimensions and position of the indicator, in local coordinates.
relativePosition: A pointer to a signed 32-bit value. On return, this value contains the new distance, in pixels, between the minimum end of the track and the near side of the indicator.

function result: A result code.

DISCUSSION

Your application can use the GetThemeTrackThumbPositionFromRegion function to respond to the kControlMsgCalcValueFromPos control definition message.

VERSION NOTES

This function is available with Appearance Manager 1.1 and later.

AVAILABILITY

Supported in Carbon. Available in Mac OS 8.1 and later when Carbon 1.0.2 or later is present.