Struct gstreamer::Preset

pub struct Preset(_, _);

This interface offers methods to query and manipulate parameter preset sets. A preset is a bunch of property settings, together with meta data and a name. The name of a preset serves as key for subsequent method calls to manipulate single presets. All instances of one type will share the list of presets. The list is created on demand, if presets are not used, the list is not created.

The interface comes with a default implementation that serves most plugins. Wrapper plugins will override most methods to implement support for the native preset format of those wrapped plugins. One method that is useful to be overridden is Preset::get_property_names. With that one can control which properties are saved and in which order. When implementing support for read-only presets, one should set the vmethods for Preset::save_preset and Preset::delete_preset to None. Applications can use Preset::is_editable to check for that.

The default implementation supports presets located in a system directory, application specific directory and in the users home directory. When getting a list of presets individual presets are read and overlaid in 1) system,

2. application and 3) user order. Whenever an earlier entry is newer, the later entries will be updated. Since 1.8 you can also provide extra paths where to find presets through the GST_PRESET_PATH environment variable. Presets found in those paths will be concidered as "app presets".

Implements

PresetExt

Methods

impl Preset

pub fn get_app_dir() -> Option<PathBuf>

Gets the directory for application specific presets if set by the application.

Returns

the directory or None, don't free or modify the string

pub fn set_app_dir<P: AsRef<Path>>(app_dir: P) -> Result<(), BoolError>

Sets an extra directory as an absolute path that should be considered when looking for presets. Any presets in the application dir will shadow the system presets.

app_dir

the application specific preset dir

Returns

true for success, false if the dir already has been set

Trait Implementations

impl Clone for Preset

fn clone(&self) -> Preset

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Hash for Preset

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

Feeds this value into the given [Hasher].

fn hash_slice<H>(data: &[Self], state: &mut H) where     H: Hasher,

Feeds a slice of this type into the given [Hasher].

impl Ord for Preset

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

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

Compares and returns the minimum of two values.

impl StaticType for Preset

fn static_type() -> Type

Returns the type identifier of Self.

impl<T: IsA<Object>> PartialEq<T> for Preset

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

This method tests for self and other values to be equal, and is used by ==.

#[must_use] fn ne(&self, other: &Rhs) -> bool

This method tests for !=.

impl Eq for Preset

impl<T: IsA<Object>> PartialOrd<T> for Preset

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

This method returns an ordering between self and other values if one exists.

#[must_use] fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

#[must_use] fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

#[must_use] fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

#[must_use] fn ge(&self, other: &Rhs) -> bool

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

impl Debug for Preset

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

Formats the value using the given formatter.

impl IsA<Object> for Preset

impl Send for Preset

impl Sync for Preset