Struct VZGraphicsDisplay

Source

#[repr(C)]
pub struct VZGraphicsDisplay { /* private fields */ }

Available on crate feature VZGraphicsDisplay only.

Expand description

Class representing a graphics display in a virtual machine.

VZGraphicsDisplay should not be instantiated directly.

Graphics displays are first configured on a VZGraphicsDeviceConfiguration subclass. When a VZVirtualMachine is created from the configuration, the displays are available through the VZGraphicsDevice’s displays property.

See: VZMacGraphicsDisplayConfiguration

See: VZVirtioGraphicsScanoutConfiguration

Implementations§

Source §

pub unsafe fn sizeInPixels(&self) -> CGSize

Available on crate feature objc2-core-foundation only.

The size of the display, in pixels.

Source

pub unsafe fn reconfigureWithSizeInPixels_error( &self, size_in_pixels: CGSize, ) -> Result<(), Retained<NSError>>

Available on crate feature objc2-core-foundation only.

Resize this display.

Parameter sizeInPixels: New display width and height in pixels.

Parameter error: If not nil, assigned with an error describing why the new size is not valid.

Returns: YES if the resize is successful, NO otherwise.

If successful, the new size will be passed to the guest but the guest may or may not respond to the new size. The guest not using the size does not return an error.

Reconfiguration triggers a display state change which can be tracked by VZGraphicsDisplayObservers.

Source

pub unsafe fn reconfigureWithConfiguration_error( &self, configuration: &VZGraphicsDisplayConfiguration, ) -> Result<(), Retained<NSError>>

Available on crate feature VZGraphicsDisplayConfiguration only.

Reconfigure this display.

Parameter configuration: New display configuration.

Parameter error: If not nil, assigned with an error describing why the new configuration is not valid.

Returns: YES if the reconfiguration is successful, NO otherwise.

The type of the configuration must match the corresponding type that caused this display to be created.

If successful, the new configuration will be passed to the guest but the guest may or may not respond to parts of the configuration. The guest not using the new configuration does not return an error.

Reconfiguration triggers a display state change which can be tracked by VZGraphicsDisplayObservers.

Source

pub unsafe fn addObserver( &self, observer: &ProtocolObject<dyn VZGraphicsDisplayObserver>, )

Add an observer.

Parameter observer: The new observer to be notified of display state changes.

Source

pub unsafe fn removeObserver( &self, observer: &ProtocolObject<dyn VZGraphicsDisplayObserver>, )

Remove an observer.

Parameter observer: The observer to be removed.

Methods from Deref<Target = NSObject>§

Source

pub fn doesNotRecognizeSelector(&self, sel: Sel) -> !

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>§

Source

pub fn class(&self) -> &'static AnyClass

Dynamically find the class of this object.

§Panics

May panic if the object is invalid (which may be the case for objects returned from unavailable init/new methods).

§Example

Check that an instance of NSObject has the precise class NSObject.

use objc2::ClassType;
use objc2::runtime::NSObject;

let obj = NSObject::new();
assert_eq!(obj.class(), NSObject::class());

Source

pub unsafe fn get_ivar<T>(&self, name: &str) -> &T
where T: Encode,

👎Deprecated: this is difficult to use correctly, use Ivar::load instead.

Use Ivar::load instead.

§Safety

The object must have an instance variable with the given name, and it must be of type T.

See Ivar::load_ptr for details surrounding this.

Source

pub fn downcast_ref<T>(&self) -> Option<&T>
where T: DowncastTarget,

Attempt to downcast the object to a class of type T.

This is the reference-variant. Use Retained::downcast if you want to convert a retained object to another type.

§Mutable classes

Some classes have immutable and mutable variants, such as NSString and NSMutableString.

When some Objective-C API signature says it gives you an immutable class, it generally expects you to not mutate that, even though it may technically be mutable “under the hood”.

So using this method to convert a NSString to a NSMutableString, while not unsound, is generally frowned upon unless you created the string yourself, or the API explicitly documents the string to be mutable.

See Apple’s documentation on mutability and on isKindOfClass: for more details.

§Generic classes

Objective-C generics are called “lightweight generics”, and that’s because they aren’t exposed in the runtime. This makes it impossible to safely downcast to generic collections, so this is disallowed by this method.

You can, however, safely downcast to generic collections where all the type-parameters are AnyObject.

§Panics

This works internally by calling isKindOfClass:. That means that the object must have the instance method of that name, and an exception will be thrown (if CoreFoundation is linked) or the process will abort if that is not the case. In the vast majority of cases, you don’t need to worry about this, since both root objects NSObject and NSProxy implement this method.

§Examples

Cast an NSString back and forth from NSObject.

use objc2::rc::Retained;
use objc2_foundation::{NSObject, NSString};

let obj: Retained<NSObject> = NSString::new().into_super();
let string = obj.downcast_ref::<NSString>().unwrap();
// Or with `downcast`, if we do not need the object afterwards
let string = obj.downcast::<NSString>().unwrap();

Try (and fail) to cast an NSObject to an NSString.

use objc2_foundation::{NSObject, NSString};

let obj = NSObject::new();
assert!(obj.downcast_ref::<NSString>().is_none());

Try to cast to an array of strings.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);
// This is invalid and doesn't type check.
let arr = arr.downcast_ref::<NSArray<NSString>>();

This fails to compile, since it would require enumerating over the array to ensure that each element is of the desired type, which is a performance pitfall.

Downcast when processing each element instead.

use objc2_foundation::{NSArray, NSObject, NSString};

let arr = NSArray::from_retained_slice(&[NSObject::new()]);

for elem in arr {
    if let Some(data) = elem.downcast_ref::<NSString>() {
        // handle `data`
    }
}