Progress controls

A progress bar is a window that an application can use to indicate the progress of a lengthy operation. It consists of a rectangle that is gradually filled with the system highlight color as an operation progresses

Range and Current Position

A progress bar's range represents the entire duration of the operation, and the current position represents the progress that the application has made toward completing the operation. The window procedure uses the range and the current position to determine the percentage of the progress bar to fill with the highlight color. Because the range and current position values are expressed as unsigned integers, the highest possible range or current position value is 65,535.

The minimum value in the range can be from 0 to 65,535. Likewise, the maximum value can be from 0 to 65,535. If you do not set the range values, the system sets the minimum value to 0 and the maximum value to 100. You can adjust the range to convenient integers by using the PBM_SETRANGE message.

A progress bar provides several messages that you can use to set the current position. The PBM_SETPOS message sets the position to a given value. The PBM_DELTAPOS message advances the position by adding a specified value to the current position.

The PBM_SETSTEP message allows you to specify a step increment for a progress bar. Subsequently, whenever you send the PBM_STEPIT message to the progress bar, the current position advances by the specified increment. By default, the step increment is set to 10.