Struct BETextDocumentContext

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pub struct BETextDocumentContext { /* private fields */ }

Available on crate feature BETextDocumentContext only.

Expand description

Apple’s documentation

Implementations§

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impl BETextDocumentContext

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pub unsafe fn initWithSelectedText_contextBefore_contextAfter_markedText_selectedRangeInMarkedText( this: Allocated<Self>, selected_text: Option<&NSString>, context_before: Option<&NSString>, context_after: Option<&NSString>, marked_text: Option<&NSString>, selected_range_in_marked_text: NSRange, ) -> Retained<Self>

Initializes a new document context with plain text.

Parameter selectedText: The currently selected text, or nil in the case of a caret selection. This string may be empty but non-nil if non-textual content is selected, in which case a single call to -deleteBackward will not delete from contextBeforeSelection. May be empty if its outside of the context’s area, even if it exists elsewhere in the document.

Parameter contextBefore: A suffix of the text preceding the selection, or nil if the selection is at the beginning of the document. This text must correspond to a range that does not include any non-text content. In particular, if a context comprises k backward-deletion clusters, then k calls to -deleteBackward must delete the corresponding text from the document. The beginning of this string must lie on a word boundary (or not be inside a word at all).

Parameter contextAfter: A prefix of the text following the selection, or nil if the selection is at the end of the document. This text must correspond to a range that does not include any non-text content. The end of this string must lie on a word boundary (or not be inside a word at all).

Parameter markedText: May be empty if it’s outside of the context’s area, even if it exists elsewhere in the document.

Parameter selectedRangeInMarkedText: The range of the current text selection, relative to the marked text range. Specify (NSNotFound, 0) if there is no marked text.

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pub unsafe fn initWithAttributedSelectedText_contextBefore_contextAfter_markedText_selectedRangeInMarkedText( this: Allocated<Self>, selected_text: Option<&NSAttributedString>, context_before: Option<&NSAttributedString>, context_after: Option<&NSAttributedString>, marked_text: Option<&NSAttributedString>, selected_range_in_marked_text: NSRange, ) -> Retained<Self>

Initializes a new document context with attributed strings. The selectedText, contextBefore, and contextAfter represent the same ranges as they do in the -initWithSelectedText:contextBefore:contextAfter: initializer.

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pub unsafe fn addTextRect_forCharacterRange(&self, rect: CGRect, range: NSRange)

Available on crate feature objc2-core-foundation only.

Adds a text rect for the given character range The CGRects representing each character range are specified in -textInputView coordinates.

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pub unsafe fn autocorrectedRanges(&self) -> Retained<NSArray<NSValue>>

Array of NSRange values, relative to the full context string made by combining the contextBefore, markedText (or selectedText if the marked text is empty), and the contextAfter.

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pub unsafe fn setAutocorrectedRanges( &self, autocorrected_ranges: &NSArray<NSValue>, )

Setter for autocorrectedRanges.

This is copied when set.

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pub unsafe fn new(&self) -> Retained<Self>

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pub unsafe fn init(this: Allocated<Self>) -> Retained<Self>

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impl BETextDocumentContext

Methods declared on superclass NSObject.

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pub unsafe fn new_class() -> Retained<Self>

Methods from Deref<Target = NSObject>§

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

Handle messages the object doesn’t recognize.

See Apple’s documentation for details.

Methods from Deref<Target = AnyObject>§

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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());

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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.

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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`
    }
}