Struct gtk::CellRenderer [−][src]
pub struct CellRenderer(_);
Expand description
The CellRenderer
is a base class of a set of objects used for
rendering a cell to a cairo::Context
. These objects are used primarily by
the TreeView
widget, though they aren’t tied to them in any
specific way. It is worth noting that CellRenderer
is not a
Widget
and cannot be treated as such.
The primary use of a CellRenderer
is for drawing a certain graphical
elements on a cairo::Context
. Typically, one cell renderer is used to
draw many cells on the screen. To this extent, it isn’t expected that a
CellRenderer keep any permanent state around. Instead, any state is set
just prior to use using GObjects
property system. Then, the
cell is measured using gtk_cell_renderer_get_size()
. Finally, the cell
is rendered in the correct location using CellRendererExt::render()
.
There are a number of rules that must be followed when writing a new
CellRenderer
. First and foremost, it’s important that a certain set
of properties will always yield a cell renderer of the same size,
barring a GtkStyle
change. The CellRenderer
also has a number of
generic properties that are expected to be honored by all children.
Beyond merely rendering a cell, cell renderers can optionally
provide active user interface elements. A cell renderer can be
“activatable” like CellRendererToggle
,
which toggles when it gets activated by a mouse click, or it can be
“editable” like CellRendererText
, which
allows the user to edit the text using a widget implementing the
CellEditable
interface, e.g. Entry
.
To make a cell renderer activatable or editable, you have to
implement the GtkCellRendererClass.activate
or
GtkCellRendererClass.start_editing
virtual functions, respectively.
Many properties of CellRenderer
and its subclasses have a
corresponding “set” property, e.g. “cell-background-set” corresponds
to “cell-background”. These “set” properties reflect whether a property
has been set or not. You should not set them independently.
This is an Abstract Base Class, you cannot instantiate it.
Implements
Trait Implementations
This method returns an ordering between self
and other
values if one exists. Read more
This method tests less than (for self
and other
) and is used by the <
operator. Read more
This method tests less than or equal to (for self
and other
) and is used by the <=
operator. Read more
This method tests greater than (for self
and other
) and is used by the >
operator. Read more
Returns the type identifier of Self
.
Auto Trait Implementations
impl RefUnwindSafe for CellRenderer
impl !Send for CellRenderer
impl !Sync for CellRenderer
impl Unpin for CellRenderer
impl UnwindSafe for CellRenderer
Blanket Implementations
Mutably borrows from an owned value. Read more
Upcasts an object to a superclass or interface T
. Read more
Upcasts an object to a reference of its superclass or interface T
. Read more
Tries to downcast to a subclass or interface implementor T
. Read more
Tries to downcast to a reference of its subclass or interface implementor T
. Read more
Tries to cast to an object of type T
. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast
and upcast
will do many checks at compile-time already. Read more
Tries to cast to reference to an object of type T
. This handles upcasting, downcasting
and casting between interface and interface implementors. All checks are performed at
runtime, while downcast
and upcast
will do many checks at compile-time already. Read more
Casts to T
unconditionally. Read more
Casts to &T
unconditionally. Read more
Returns true
if the object is an instance of (can be cast to) T
.
pub fn set_properties_from_value(
&self,
property_values: &[(&str, Value)]
) -> Result<(), BoolError>
pub fn set_property<'a, N, V>(
&self,
property_name: N,
value: V
) -> Result<(), BoolError> where
V: ToValue,
N: Into<&'a str>,
pub fn set_property_from_value<'a, N>(
&self,
property_name: N,
value: &Value
) -> Result<(), BoolError> where
N: Into<&'a str>,
Safety Read more
Safety Read more
Safety Read more
Safety Read more
pub fn connect_notify<F>(&self, name: Option<&str>, f: F) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec) + Send + Sync,
pub fn connect_notify_local<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: 'static + Fn(&T, &ParamSpec),
pub unsafe fn connect_notify_unsafe<F>(
&self,
name: Option<&str>,
f: F
) -> SignalHandlerId where
F: Fn(&T, &ParamSpec),
pub fn has_property<'a, N>(&self, property_name: N, type_: Option<Type>) -> bool where
N: Into<&'a str>,
pub fn find_property<'a, N>(&self, property_name: N) -> Option<ParamSpec> where
N: Into<&'a str>,
pub fn connect<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + Send + Sync + 'static,
N: Into<&'a str>,
Same as connect
but takes a SignalId
instead of a signal name.
pub fn connect_local<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value> + 'static,
N: Into<&'a str>,
Same as connect_local
but takes a SignalId
instead of a signal name.
pub unsafe fn connect_unsafe<'a, N, F>(
&self,
signal_name: N,
after: bool,
callback: F
) -> Result<SignalHandlerId, BoolError> where
F: Fn(&[Value]) -> Option<Value>,
N: Into<&'a str>,
Same as connect_unsafe
but takes a SignalId
instead of a signal name.
Emit signal by signal id.
Emit signal with details by signal id.
Emit signal by it’s name.
pub fn bind_property<'a, O, N, M>(
&'a self,
source_property: N,
target: &'a O,
target_property: M
) -> BindingBuilder<'a> where
O: ObjectType,
N: Into<&'a str>,
M: Into<&'a str>,
Same as emit
but takes Value
for the arguments.
Same as emit_by_name
but takes Value
for the arguments.
Returns a SendValue
clone of self
.
impl<'a, T, C> FromValueOptional<'a> for T where
C: ValueTypeChecker<Error = ValueTypeMismatchOrNoneError>,
T: FromValue<'a, Checker = C>,