GtkProgressBar

A widget for displaying incremental or continuous progress.

Object Hierarchy

  GObject
  GtkObject
  GtkWidget
  GtkProgress
  GtkProgressBar

Description

The GtkProgressBar is typically used to display the progress of a long running operation. It provides a visual clue that processing is underway. The GtkProgressBar can be used in two different modes: percentage mode and activity mode.

When an application can determine how much work needs to take place (e.g. read a fixed number of bytes from a file) and can monitor its progress, it can use the GtkProgressBar in percentage mode and the user sees a growing bar indicating the percentage of the work that has been completed. In this mode, the application is required to call set_fraction() periodically to update the progress bar.

When an application has no accurate way of knowing the amount of work to do, it can use the GtkProgressBar in activity mode, which shows activity by a block moving back and forth within the progress area. In this mode, the application is required to call pulse() perodically to update the progress bar.

There is quite a bit of flexibility provided to control the appearance of the GtkProgressBar. Functions are provided to control the orientation of the bar, optional text can be displayed along with the bar, and the step size used in activity mode can be set.

The progress bar is not updated after calling pulse() or set_fraction() , but in the main loop. This means that, in a long running operation, you need to let the UI update itself by using main_iteration() .