LevelBar
GtkLevelBar
is a widget that can be used as a level indicator.
Typical use cases are displaying the strength of a password, or showing the charge level of a battery.
Use method@Gtk.LevelBar.set_value to set the current value, and method@Gtk.LevelBar.add_offset_value to set the value offsets at which the bar will be considered in a different state. GTK will add a few offsets by default on the level bar: %GTK_LEVEL_BAR_OFFSET_LOW, %GTK_LEVEL_BAR_OFFSET_HIGH and %GTK_LEVEL_BAR_OFFSET_FULL, with values 0.25, 0.75 and 1.0 respectively.
Note that it is your responsibility to update preexisting offsets when changing the minimum or maximum value. GTK will simply clamp them to the new range.
Adding a custom offset on the bar
static GtkWidget *
create_level_bar (void)
{
GtkWidget *widget;
GtkLevelBar *bar;
widget = gtk_level_bar_new ();
bar = GTK_LEVEL_BAR (widget);
// This changes the value of the default low offset
gtk_level_bar_add_offset_value (bar,
GTK_LEVEL_BAR_OFFSET_LOW,
0.10);
// This adds a new offset to the bar; the application will
// be able to change its color CSS like this:
//
// levelbar block.my-offset {
// background-color: magenta;
// border-style: solid;
// border-color: black;
// border-width: 1px;
// }
gtk_level_bar_add_offset_value (bar, "my-offset", 0.60);
return widget;
}
The default interval of values is between zero and one, but it’s possible to modify the interval using method@Gtk.LevelBar.set_min_value and method@Gtk.LevelBar.set_max_value. The value will be always drawn in proportion to the admissible interval, i.e. a value of 15 with a specified interval between 10 and 20 is equivalent to a value of 0.5 with an interval between 0 and 1. When %GTK_LEVEL_BAR_MODE_DISCRETE is used, the bar level is rendered as a finite number of separated blocks instead of a single one. The number of blocks that will be rendered is equal to the number of units specified by the admissible interval.
For instance, to build a bar rendered with five blocks, it’s sufficient to set the minimum value to 0 and the maximum value to 5 after changing the indicator mode to discrete.
GtkLevelBar as GtkBuildable
The GtkLevelBar
implementation of the GtkBuildable
interface supports a custom <offsets>
element, which can contain any number of <offset>
elements, each of which must have "name" and "value" attributes.
CSS nodes
levelbar[.discrete]
╰── trough
├── block.filled.level-name
┊
├── block.empty
┊
GtkLevelBar
has a main CSS node with name levelbar and one of the style classes .discrete or .continuous and a subnode with name trough. Below the trough node are a number of nodes with name block and style class .filled or .empty. In continuous mode, there is exactly one node of each, in discrete mode, the number of filled and unfilled nodes corresponds to blocks that are drawn. The block.filled nodes also get a style class .level-name corresponding to the level for the current value.
In horizontal orientation, the nodes are always arranged from left to right, regardless of text direction.
Accessibility
GtkLevelBar
uses the %GTK_ACCESSIBLE_ROLE_METER role.
Skipped during bindings generation
parameter
value
: value: Out parameter is not supported
Constructors
Properties
The accessible role of the given GtkAccessible
implementation.
A list of css classes applied to this widget.
Whether the widget should grab focus when it is clicked with the mouse.
Enables or disables the emission of the ::query-tooltip signal on @widget.
Whether to use the hexpand
property.
The GtkLayoutManager
instance to use to compute the preferred size of the widget, and allocate its children.
Margin on bottom side of widget.
Margin on start of widget, horizontally.
Determines the way GtkLevelBar
interprets the value properties to draw the level fill area.
The orientation of the orientable.
Whether the widget will receive the default action when it is focused.
The scale factor of the widget.
Sets the text of tooltip to be the given string, which is marked up with Pango markup.
Sets the text of tooltip to be the given string.
Whether to use the vexpand
property.
Functions
Enable or disable an action installed with gtk_widget_class_install_action().
Looks up the action in the action groups associated with
Activates the default.activate
action from @widget.
For widgets that can be “activated” (buttons, menu items, etc.), this function activates them.
Adds @controller to @widget so that it will receive events.
Adds a style class to @widget.
Adds a widget to the list of mnemonic labels for this widget.
Adds a new offset marker on @self at the position specified by @value.
Queues an animation frame update and adds a callback to be called before each frame.
This function is only used by GtkWidget
subclasses, to assign a size, position and (optionally) baseline to their child widgets.
Requests the user's screen reader to announce the given message.
Called by widgets as the user moves around the window using keyboard shortcuts.
Computes the bounds for @widget in the coordinate space of @target.
Computes whether a container should give this widget extra space when possible.
Translates the given @point in @widget's coordinates to coordinates relative to @target’s coordinate system.
Computes a matrix suitable to describe a transformation from
Signals that all holders of a reference to the widget should release the reference that they hold.
Emitted when the text direction of a widget changes.
Emitted when @widget is hidden.
Emitted if keyboard navigation fails.
Emitted when @widget is going to be mapped.
Emitted when a widget is activated via a mnemonic.
Emitted when the focus is moved.
Emitted when an offset specified on the bar changes value.
Emitted when the widget’s tooltip is about to be shown.
Emitted when @widget is associated with a GdkSurface
.
Emitted when @widget is shown.
Emitted when the widget state changes.
Emitted when @widget is going to be unmapped.
Emitted when the GdkSurface
associated with @widget is destroyed.
Creates a new PangoContext
with the appropriate font map, font options, font description, and base direction for drawing text for this widget.
Creates a new PangoLayout
with the appropriate font map, font description, and base direction for drawing text for this widget.
Clears the template children for the given widget.
Checks to see if a drag movement has passed the GTK drag threshold.
Retrieves the accessible parent for an accessible object.
Retrieves the accessible role of an accessible object.
Returns the baseline that has currently been allocated to @widget.
Returns the height that has currently been allocated to @widget.
Returns the width that has currently been allocated to @widget.
Gets the first ancestor of @widget with type @widget_type.
Retrieves the accessible implementation for the given GtkAccessible
.
Returns the baseline that has currently been allocated to @widget.
Gets the ID of the @buildable object.
Gets the value set with gtk_widget_set_child_visible().
Gets the clipboard object for @widget.
Gets the reading direction for a particular widget.
Get the GdkDisplay
for the toplevel window associated with this widget.
Retrieves the first accessible child of an accessible object.
Returns the widget’s first child.
Returns the current focus child of @widget.
Gets the font map of @widget.
Obtains the frame clock for a widget.
Returns the widget’s last child.
Retrieves the next accessible sibling of an accessible object
Returns the widget’s next sibling.
Retrieves the orientation of the @orientable.
Gets a PangoContext
with the appropriate font map, font description, and base direction for this widget.
Query a platform state, such as focus.
Retrieves the minimum and natural size of a widget, taking into account the widget’s preference for height-for-width management.
Returns the widget’s previous sibling.
Gets the primary clipboard of @widget.
Determines whether @widget is realized.
Gets whether the widget prefers a height-for-width layout or a width-for-height layout.
Returns the widget’s sensitivity.
Gets the settings object holding the settings used for this widget.
Returns the content width or height of the widget.
Returns the widget state as a flag set.
Returns the style context associated to @widget.
Fetch an object build from the template XML for @widget_type in this @widget instance.
Determines whether the widget is visible.
Returns whether @css_class is currently applied to @widget.
Determines whether @widget is the current default widget within its toplevel.
Determines if the widget should show a visible indication that it has the global input focus.
Returns whether the widget is currently being destroyed.
Creates and initializes child widgets defined in templates.
Inserts @group into @widget.
Inserts @widget into the child widget list of @parent.
Inserts @widget into the child widget list of @parent.
Determines whether @widget is somewhere inside @ancestor, possibly with intermediate containers.
Determines whether @widget can be drawn to.
Returns the widget’s effective sensitivity.
Emits the ::keynav-failed
signal on the widget.
Returns the widgets for which this widget is the target of a mnemonic.
Emits the ::mnemonic-activate signal.
Returns a GListModel
to track the children of @widget.
Returns a GListModel
to track the class@Gtk.EventControllers of @widget.
Flags the widget for a rerun of the vfunc@Gtk.Widget.size_allocate function.
Flags a widget to have its size renegotiated.
Removes @controller from @widget, so that it doesn't process events anymore.
Removes a style from @widget.
Removes a widget from the list of mnemonic labels for this widget.
Removes an offset marker from a GtkLevelBar
.
Removes a tick callback previously registered with gtk_widget_add_tick_callback().
Resets the accessible @property to its default value.
Resets the accessible @relation to its default value.
Resets the accessible @state to its default value.
Sets the parent and sibling of an accessible object.
Sets whether @widget should be mapped along with its parent.
Sets a named cursor to be shown when pointer devices point towards @widget.
Sets the reading direction on a particular widget.
Set @child as the current focus child of @widget.
Sets the font map to use for Pango rendering.
Set all margins to the same value.
Set start and end margin to horizontal and top and bottom margin to vertical
Set margins.
Sets the orientation of the @orientable.
Sets the sensitivity of a widget.
Sets the minimum size of a widget.
Turns on flag values in the current widget state.
Sets the visibility state of @widget.
Returns whether @widget should contribute to the measuring and allocation of its parent.
Triggers a tooltip query on the display where the toplevel of @widget is located.
Turns off flag values for the current widget state.
Updates the next accessible sibling of @self.