Graphics.UI.Gtk.Display.ProgressBar

A widget which indicates progress visually

Detail

The ProgressBar is typically used to display the progress of a long running operation. It provides a visual clue that processing is underway. The ProgressBar 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 ProgressBar 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 progressBarSetFraction 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 ProgressBar 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 progressBarPulse perodically to update the progress bar.

There is quite a bit of flexibility provided to control the appearance of the ProgressBar. 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.

Class Hierarchy

| GObject
| +----Object
| +----Widget
| +----ProgressBar

Types

data ProgressBar

Instances

Eq ProgressBar

Ord ProgressBar

GObjectClass ProgressBar

ProgressBarClass ProgressBar

WidgetClass ProgressBar

class WidgetClass o => ProgressBarClass o

Instances

ProgressBarClass ProgressBar

castToProgressBar :: GObjectClass obj => obj -> ProgressBar

gTypeProgressBar :: GType

toProgressBar :: ProgressBarClass o => o -> ProgressBar

Constructors

progressBarNew :: IO ProgressBar

Creates a new ProgressBar.

Methods

progressBarPulse :: ProgressBarClass self => self -> IO ()

Indicates that some progress is made, but you don't know how much. Causes the progress bar to enter "activity mode", where a block bounces back and forth. Each call to progressBarPulse causes the block to move by a little bit (the amount of movement per pulse is determined by progressBarSetPulseStep).

progressBarSetText :: (ProgressBarClass self, GlibString string) => self -> string -> IO ()

Causes the given text to appear superimposed on the progress bar.

progressBarSetFraction

Arguments

:: ProgressBarClass self

=> self

-> Double

fraction - fraction of the task that's been completed

-> IO ()

Causes the progress bar to "fill in" the given fraction of the bar. The fraction should be between 0.0 and 1.0, inclusive.

progressBarSetPulseStep

Arguments

:: ProgressBarClass self

=> self

-> Double

fraction - fraction between 0.0 and 1.0

-> IO ()

Sets the fraction of total progress bar length to move the bouncing block for each call to progressBarPulse.

progressBarGetFraction

Arguments

:: ProgressBarClass self

=> self

-> IO Double

returns a fraction from 0.0 to 1.0

Returns the current fraction of the task that's been completed.

progressBarGetPulseStep

Arguments

:: ProgressBarClass self

=> self

-> IO Double

returns a fraction from 0.0 to 1.0

Retrieves the pulse step set with progressBarSetPulseStep

progressBarGetText

Arguments

:: (ProgressBarClass self, GlibString string)

=> self

-> IO (Maybe string)

returns text, or Nothing

Retrieves the text displayed superimposed on the progress bar, if any, otherwise Nothing.

progressBarSetEllipsize :: ProgressBarClass self => self -> EllipsizeMode -> IO ()

Sets the mode used to ellipsize (add an ellipsis: "...") the text if there is not enough space to render the entire string.

• Available since Gtk+ version 2.6

progressBarGetEllipsize :: ProgressBarClass self => self -> IO EllipsizeMode

Returns the ellipsizing position of the progressbar. See progressBarSetEllipsize.

• Available since Gtk+ version 2.6

Attributes

progressBarDiscreteBlocks :: ProgressBarClass self => Attr self Int

The number of discrete blocks in a progress bar (when shown in the discrete style).

Allowed values: >= 2

Default value: 10

progressBarFraction :: ProgressBarClass self => Attr self Double

The fraction of total work that has been completed.

Allowed values: [0,1]

Default value: 0

progressBarPulseStep :: ProgressBarClass self => Attr self Double

The fraction of total progress to move the bouncing block when pulsed.

Allowed values: [0,1]

Default value: 0.1

progressBarText :: (ProgressBarClass self, GlibString string) => ReadWriteAttr self (Maybe string) string

Text to be displayed in the progress bar.

Default value: "%P %%"

progressBarEllipsize :: ProgressBarClass self => Attr self EllipsizeMode

The preferred place to ellipsize the string, if the progressbar does not have enough room to display the entire string, specified as a EllipsizeMode.

Note that setting this property to a value other than EllipsizeNone has the side-effect that the progressbar requests only enough space to display the ellipsis "...". Another means to set a progressbar's width is widgetSetSizeRequest.

Default value: EllipsizeNone