Struct gtk4::Tooltip

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pub struct Tooltip { /* private fields */ }
Expand description

Tooltip is an object representing a widget tooltip.

Basic tooltips can be realized simply by using WidgetExt::set_tooltip_text() or WidgetExt::set_tooltip_markup() without any explicit tooltip object.

When you need a tooltip with a little more fancy contents, like adding an image, or you want the tooltip to have different contents per TreeView row or cell, you will have to do a little more work:

  • Set the has-tooltip property to true. This will make GTK monitor the widget for motion and related events which are needed to determine when and where to show a tooltip.

  • Connect to the query-tooltip signal. This signal will be emitted when a tooltip is supposed to be shown. One of the arguments passed to the signal handler is a Tooltip object. This is the object that we are about to display as a tooltip, and can be manipulated in your callback using functions like set_icon(). There are functions for setting the tooltip’s markup, setting an image from a named icon, or even putting in a custom widget.

  • Return true from your ::query-tooltip handler. This causes the tooltip to be show. If you return false, it will not be shown.

§Implements

[trait@glib::ObjectExt]

Implementations§

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impl Tooltip

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pub fn set_custom(&self, custom_widget: Option<&impl IsA<Widget>>)

Replaces the widget packed into the tooltip with @custom_widget. @custom_widget does not get destroyed when the tooltip goes away. By default a box with a Image and Label is embedded in the tooltip, which can be configured using gtk_tooltip_set_markup() and gtk_tooltip_set_icon().

§custom_widget

a Widget, or None to unset the old custom widget.

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pub fn set_icon(&self, paintable: Option<&impl IsA<Paintable>>)

Sets the icon of the tooltip (which is in front of the text) to be @paintable. If @paintable is None, the image will be hidden.

§paintable

a gdk::Paintable

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pub fn set_icon_from_gicon(&self, gicon: Option<&impl IsA<Icon>>)

Sets the icon of the tooltip (which is in front of the text) to be the icon indicated by @gicon with the size indicated by @size. If @gicon is None, the image will be hidden.

§gicon

a GIcon representing the icon

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pub fn set_icon_from_icon_name(&self, icon_name: Option<&str>)

Sets the icon of the tooltip (which is in front of the text) to be the icon indicated by @icon_name with the size indicated by @size. If @icon_name is None, the image will be hidden.

§icon_name

an icon name

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pub fn set_markup(&self, markup: Option<&str>)

Sets the text of the tooltip to be @markup.

The string must be marked up with Pango markup. If @markup is None, the label will be hidden.

§markup

a string with Pango markup or NLL

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pub fn set_text(&self, text: Option<&str>)

Sets the text of the tooltip to be @text.

If @text is None, the label will be hidden. See also set_markup().

§text

a text string

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pub fn set_tip_area(&self, rect: &Rectangle)

Sets the area of the widget, where the contents of this tooltip apply, to be @rect (in widget coordinates). This is especially useful for properly setting tooltips on TreeView rows and cells, GtkIconViews, etc.

For setting tooltips on TreeView, please refer to the convenience functions for this: gtk_tree_view_set_tooltip_row() and gtk_tree_view_set_tooltip_cell().

§rect

a gdk::Rectangle

Trait Implementations§

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impl Clone for Tooltip

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fn clone(&self) -> Self

Returns a copy of the value. Read more
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fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source. Read more
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impl Debug for Tooltip

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fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter. Read more
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impl HasParamSpec for Tooltip

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type ParamSpec = ParamSpecObject

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type SetValue = Tooltip

Preferred value to be used as setter for the associated ParamSpec.
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type BuilderFn = fn(_: &str) -> ParamSpecObjectBuilder<'_, Tooltip>

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fn param_spec_builder() -> Self::BuilderFn

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impl Hash for Tooltip

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fn hash<H>(&self, state: &mut H)
where H: Hasher,

Feeds this value into the given Hasher. Read more
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fn hash_slice<H>(data: &[Self], state: &mut H)
where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher. Read more
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impl Ord for Tooltip

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fn cmp(&self, other: &Self) -> Ordering

This method returns an Ordering between self and other. Read more
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fn max(self, other: Self) -> Self
where Self: Sized,

Compares and returns the maximum of two values. Read more
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fn min(self, other: Self) -> Self
where Self: Sized,

Compares and returns the minimum of two values. Read more
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fn clamp(self, min: Self, max: Self) -> Self
where Self: Sized + PartialOrd,

Restrict a value to a certain interval. Read more
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impl ParentClassIs for Tooltip

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impl<OT: ObjectType> PartialEq<OT> for Tooltip

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fn eq(&self, other: &OT) -> bool

This method tests for self and other values to be equal, and is used by ==.
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fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.
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impl<OT: ObjectType> PartialOrd<OT> for Tooltip

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fn partial_cmp(&self, other: &OT) -> Option<Ordering>

This method returns an ordering between self and other values if one exists. Read more
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fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator. Read more
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fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator. Read more
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fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator. Read more
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fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator. Read more
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impl StaticType for Tooltip

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fn static_type() -> Type

Returns the type identifier of Self.
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impl Eq for Tooltip

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impl<O> GObjectPropertyExpressionExt for O
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fn property_expression(&self, property_name: &str) -> PropertyExpression

Create an expression looking up an object’s property.
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Create an expression looking up an object’s property with a weak reference.
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Sets the property property_name of the object to value value. Read more
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Sets multiple properties of the object at once. Read more
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Gets the property property_name of the object and cast it to the type V. Read more
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Check if the object has a property property_name of the given type_. Read more
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Get the type of the property property_name of this object. Read more
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Get the ParamSpec of the property property_name of this object.
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Return all ParamSpec of the properties of this object.
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Freeze all property notifications until the return guard object is dropped. Read more
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where QD: 'static,

Retrieve previously set arbitrary data of this object with the given key. Read more
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where QD: 'static,

Set arbitrary data on this object with the given key. Read more
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Block a given signal handler. Read more
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Unblock a given signal handler.
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Stop emission of the currently emitted signal.
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Stop emission of the currently emitted signal by the (possibly detailed) signal name.
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Connect to the signal signal_name on this object. Read more
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Connect to the signal signal_id on this object. Read more
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Limits the lifetime of closure to the lifetime of the object. When the object’s reference count drops to zero, the closure will be invalidated. An invalidated closure will ignore any calls to invoke_with_values, or invoke when using Rust closures.
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fn disconnect(&self, handler_id: SignalHandlerId)

Disconnect a previously connected signal handler.
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fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId
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Connect to the notify signal of the object. Read more
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Connect to the notify signal of the object. Read more
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Connect to the notify signal of the object. Read more
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fn notify(&self, property_name: &str)

Notify that the given property has changed its value. Read more
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Notify that the given property has changed its value. Read more
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Downgrade this object to a weak reference.
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Add a callback to be notified when the Object is disposed.
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fn bind_property<'a, 'f, 't, O>( &'a self, source_property: &'a str, target: &'a O, target_property: &'a str ) -> BindingBuilder<'a, 'f, 't>
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Bind property source_property on this object to the target_property on the target object. Read more
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Returns the strong reference count of this object.
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Runs the dispose mechanism of the object. Read more
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type Value = T

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type Value = T

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Ensures that the type has been registered with the type system.
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