Crate wayland_window [−] [src]
Wayland Window, a minimalistic decoration-drawing library for wayland applications.
This crate is only usable in conjuction of the
wayland-client
crate.
Creating a decorated shell surface
Creating a decorated window is as simple as wrapping it in a
DecoratedSurface
:
use wayland_window::{DecoratedSurface, Shell}; // if using the legacy wl_shell global let shell = Shell::Wl(my_wl_shell); // if using the new not-yet-stable xdg_shell let shell = Shell::Xdg(my_xdh_shell); let decorated_surface = DecoratedSurface::new( &mut event_queue, my_implementation, my_implementation_data, &my_surface, width, height, &compositor, &subcompositor, &shm, &shell, Some(seat) ).unwrap(); // creation can fail
As you can see, you need to pass several references to global objects as well as a WlSeat
.
It is required for the library to be able to create the surfaces to draw the borders, react
to user input in the borders, for resizing and move. It will use the events provided on the
seat you passed as argument. (So if you are on a setup with more than one pointer,
only the one associated with this seat will be able to resize the window).
Configure events
The DecoratedSurface
object will not resize your window itself, as it cannot do it.
When the user clicks on a border and starts a resize, the server will start to generate a
number of configure
events on the shell surface. You'll need to process the events generated
by the surface to handle them.
The wayland server can (and will) generate a ton of configure
events during a single
WlDisplay::dispatch()
if the user is currently resizing the window. You are only required to
process the last one, and if you try to handle them all your aplication will be very
laggy.
The proper way is to accumulate them in your subhandler, overwriting the the previous one each time, and manually checking if one has been received in the main loop of your program. For example like this
use wayland_window::{DecoratedSurface, init_decorated_surface, DecoratedSurfaceImplementation}; // define a state to accumulate sizes struct ConfigureState { new_size: Option<(i32,i32)> } // insert it in your event queue state let configure_token = event_queue.state().insert(ConfigureState { new_size: None }); // use it in your implementation: let my_implementation = DecoratedSurfaceImplementation { configure: |evqh, token, _, newsize| { let configure_state: &mut ConfigureState = evqh.state().get_mut(token); configure_state.new_size = newsize; }, close: |_, _| { /* ... */ } }; // create the decorated surface: let decorated_surface = DecoratedSurface::new( &my_surface, width, height, &compositor, &subcompositor, &shm, &shell, Some(seat), true ).unwrap(); // store in it the state let decorated_token = event_queue.state().insert(decorated_surface); // now, intialize it init_decorated_surface( &mut event_queue, // the event queue my_implementation, // our implementation configure_token.clone(), // the implementation data decorated_token.clone() // token to the decorated surface ); // then, while running your event loop loop { display.flush().unwrap(); event_queue.dispatch().unwrap(); // check if a resize is needed let mut state = event_queue.state(); let mut configure_state = state.get_mut(&configure_token); if let Some((w, h)) = configure_state.new_size.take() { // The compositor suggests we take a new size of (w, h) // Handle it as needed (see next section) } }
Resizing the surface
When resizing your main surface, you need to tell the DecoratedSurface
that it
must update its dimensions. This is very simple:
// update the borders size decorated_surface.resize(width, height); // update your contents size (here by attaching a new buffer) surface.attach(Some(&new_buffer)); surface.commit();
If you do this as a response of a configure
event, note the following points:
- You do not have to respect the exact sizes provided by the compositor, it is just a hint. You can even ignore it if you don't want the window to be resized.
- In case you chose to ignore the resize, it can be appropiate to still resize your window to its current size (update the buffer to the compositor), as the compositer might have resized your window without telling you.
- The size hint provided to your implementation is a size hint for the interior of the
window: the dimensions of the border has been subtracted from the hint the compositor
gave. If you need to compute dimensions taking into account the sizes of the borders,
you can use the
add_borders
andsubtract_borders
functions.
Structs
DecoratedSurface |
A wrapper for a decorated surface. |
DecoratedSurfaceImplementation |
For handling events that occur to a DecoratedSurface. |
Enums
Configure |
Configure data for a decorated surface handler. |
Shell |
Functions
add_borders |
Adds the border dimensions to the given dimensions. |
init_decorated_surface | |
subtract_borders |
Subtracts the border dimensions from the given dimensions. |