Documentation
¶
Overview ¶
Package objc provides cached Objective-C runtime helpers.
This package wraps purego/objc to provide selector caching for better performance.
Index ¶
- Variables
- func AddMethod(cls Class, sel SEL, impl any, types string) bool
- func CallWithError(id ID, sel SEL, args ...any) error
- func ConvertSlice[T any](ids []ID, convert func(ID) T) []T
- func ConvertSliceToStrings(ids []ID) []string
- func GoString(cstr *byte) string
- func IDToString(id ID) string
- func MustSend[T any](id ID, sel SEL, args ...any) T
- func NewActionTarget(owner ID, fn func(sender ID)) (target ID, sel SEL)
- func RegisterClassPair(cls Class)
- func RespondsToSelector(id ID, sel SEL) bool
- func SafeSend[T any](id ID, sel SEL, args ...any) (T, error)
- func Send[T any](id ID, sel SEL, args ...any) T
- func SendWithError[T any](id ID, sel SEL, args ...any) (T, error)
- type Block
- type CArrayArg
- type Class
- type FieldDef
- type ID
- type IDGetter
- type MethodDef
- type Protocol
- type SEL
- type UnrecognizedSelectorError
Constants ¶
This section is empty.
Variables ¶
var ErrUnrecognizedSelector = &UnrecognizedSelectorError{}
ErrUnrecognizedSelector is returned when an object does not respond to a selector.
Functions ¶
func CallWithError ¶
CallWithError calls a void-returning selector and handles the NSError** pattern.
func ConvertSlice ¶
ConvertSlice maps []ID to []T using a converter function.
func ConvertSliceToStrings ¶
ConvertSliceToStrings maps []ID to []string via IDToString.
func GoString ¶
GoString converts a C string (*byte from UTF8String) to a Go string. This is needed because UTF8String returns const char*, not an ObjC object.
func MustSend ¶
MustSend calls a selector and panics with a clear error if the object doesn't respond. Use this when you expect the selector to always exist but want a clearer panic message than the NSInvalidArgumentException.
func NewActionTarget ¶
NewActionTarget creates an Objective-C trampoline object that calls fn when it receives the "invoke:" selector. The trampoline is associated with owner via objc_setAssociatedObject so it is retained for the owner's lifetime and cleaned up automatically when the owner is deallocated or a new action target replaces it.
Returns the trampoline ID and the selector to wire as the action.
func RegisterClassPair ¶
func RegisterClassPair(cls Class)
RegisterClassPair registers a class pair with the runtime.
func RespondsToSelector ¶
RespondsToSelector checks if an object responds to the given selector. This is the safe way to check before calling a method.
func SafeSend ¶
SafeSend calls a selector only if the object responds to it. Returns the zero value and ErrUnrecognizedSelector if the selector is not recognized. This prevents NSInvalidArgumentException crashes from unrecognized selectors.
func Send ¶
Send calls purego.Send with the given arguments. If any argument implements IDGetter (has GetID() method), the ID is automatically extracted. This allows passing struct wrappers like VZVirtualMachine directly instead of having to call .ID or .GetID() manually. Nil interface values are converted to ID(0) to avoid purego panics. When T is []ID, the return value from the ObjC call (an NSArray) is automatically converted to a Go slice via NSArrayToSlice.
Types ¶
type CArrayArg ¶
type CArrayArg struct {
// contains filtered or unexported fields
}
CArrayArg marks a Go slice argument that should be passed to Objective-C as a pointer to contiguous C array storage.
Use CArray at call sites for APIs that take `*T` and a paired `count` parameter.
type Class ¶
Type aliases for convenience
func RegisterClass ¶
func RegisterClass(name string, superClass Class, protocols []*Protocol, ivars []FieldDef, methods []MethodDef) (Class, error)
RegisterClass registers a new Objective-C class with the runtime. The class inherits from superClass and implements the given protocols. ivars defines instance variables, methods defines the class methods.
type ID ¶
Type aliases for convenience
func IDValueAt ¶ added in v0.3.6
IDValueAt loads an Objective-C object ID stored at a symbol address.
Dynamic libraries commonly export Objective-C object constants as pointers to storage containing the real object ID. Dlsym returns the storage address, so callers must load the pointer-sized value stored there.
func NSArrayToSlice ¶
NSArrayToSlice converts an NSArray ID into a []ID by calling count and objectAtIndex:.
type IDGetter ¶
type IDGetter interface {
GetID() ID
}
IDGetter is implemented by types that wrap an Objective-C object ID. This allows objc.Send to automatically extract the ID from wrapper types.
type Protocol ¶
Type aliases for convenience
func GetProtocol ¶
GetProtocol returns the protocol with the given name, or nil if not found.
type SEL ¶
Type aliases for convenience
func RegisterName ¶
RegisterName registers a selector with the Objective-C runtime. This is the same as Sel but without caching - use Sel for repeated calls.
type UnrecognizedSelectorError ¶
type UnrecognizedSelectorError struct {
Selector string
}
UnrecognizedSelectorError indicates an object does not respond to a selector.
func (*UnrecognizedSelectorError) Error ¶
func (e *UnrecognizedSelectorError) Error() string
Source Files