Struct WindowClass

pub struct WindowClass<'a> { /* private fields */ }

A window class registered with RegisterClassExW(), containing a window procedure closure. Necessary for creating windows.

• Don’t drop it before any Windows created with it, because this tries to unregister the class (struct field order is relevant).
• Don’t use Get.../SetWindowLongPtrW(...GWLP_USERDATA...) on a window created from an instance of this struct, because it stores internal data necessary for the struct to function.

Implementations

impl<'a> WindowClass<'a>

pub fn new<F>(wnd_proc: F) -> Result<Self>

where F: WndProc + 'a,

Creates a new class with a name from Self::make_name().

Pass the window procedure of the class that you implement. Its parameters are:

• Without types: hwnd, msg_id, wparam, lparam
• With types: hwnd: HWND, msg_id: u32, wparam: WPARAM, lparam: LPARAM

Return None from the procedure to cause DefWindowProcW() being called and its return value being used. You sometimes should also call it yourself when handling certain messages and returning Some(...).

Note that some functions like, e.g., DestroyWindow() and MoveWindow() synchronously cause the window procedure to be called again during their calls. This means that closing over an Rc<RefCell<...>> and calling borrow_mut() to call your actual procedure implementation (can be a method with self parameter) will cause a borrowing panic. Using Rc<ReentrantRefCell<...>> instead solves this. See crate::ReentrantRefCell for more information.

pub fn with_name<F>(name: &str, wnd_proc: F) -> Result<Self>

where F: WndProc + 'a,

pub fn with_details<F>(wnd_class_ex: WNDCLASSEXW, wnd_proc: F) -> Result<Self>

where F: WndProc + 'a,

The lpfnWndProc field will be overwritten.

pub fn make_name() -> Result<String>

Generates a time-based class name.

pub fn atom(&self) -> u16

Trait Implementations

impl Drop for WindowClass<'_>

fn drop(&mut self)

Executes the destructor for this type.