libcosmic/cosmic/cctk/sctk/reexports/client/index.html
2026-04-18 20:11:25 +00:00

136 lines
No EOL
22 KiB
HTML
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Interface for interacting with the Wayland protocol, client-side."><title>cosmic::cctk::sctk::reexports::client - Rust</title><script>if(window.location.protocol!=="file:")document.head.insertAdjacentHTML("beforeend","SourceSerif4-Regular-6b053e98.ttf.woff2,FiraSans-Italic-81dc35de.woff2,FiraSans-Regular-0fe48ade.woff2,FiraSans-MediumItalic-ccf7e434.woff2,FiraSans-Medium-e1aa3f0a.woff2,SourceCodePro-Regular-8badfe75.ttf.woff2,SourceCodePro-Semibold-aa29a496.ttf.woff2".split(",").map(f=>`<link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../../static.files/${f}">`).join(""))</script><link rel="stylesheet" href="../../../../../static.files/normalize-9960930a.css"><link rel="stylesheet" href="../../../../../static.files/rustdoc-aa0817cf.css"><meta name="rustdoc-vars" data-root-path="../../../../../" data-static-root-path="../../../../../static.files/" data-current-crate="cosmic" data-themes="" data-resource-suffix="" data-rustdoc-version="1.90.0-nightly (3048886e5 2025-07-30)" data-channel="nightly" data-search-js="search-fa3e91e5.js" data-settings-js="settings-5514c975.js" ><script src="../../../../../static.files/storage-68b7e25d.js"></script><script defer src="../../../../../crates.js"></script><script defer src="../../../../../static.files/main-eebb9057.js"></script><noscript><link rel="stylesheet" href="../../../../../static.files/noscript-32bb7600.css"></noscript><link rel="alternate icon" type="image/png" href="../../../../../static.files/favicon-32x32-6580c154.png"><link rel="icon" type="image/svg+xml" href="../../../../../static.files/favicon-044be391.svg"></head><body class="rustdoc mod crate"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="mobile-topbar"><button class="sidebar-menu-toggle" title="show sidebar"></button></nav><nav class="sidebar"><div class="sidebar-crate"><h2><a href="../../../../../cosmic/index.html">cosmic</a><span class="version">1.0.0</span></h2></div><div class="sidebar-elems"><ul class="block"><li><a id="all-types" href="all.html">All Items</a></li></ul><section id="rustdoc-toc"><h3><a href="#">Sections</a></h3><ul class="block top-toc"><li><a href="#general-concepts" title="General concepts">General concepts</a></li><li><a href="#event-dispatching" title="Event dispatching">Event dispatching</a><ul><li><a href="#the-dispatch-trait-and-dispatch-delegation" title="The `Dispatch` trait and dispatch delegation">The <code>Dispatch</code> trait and dispatch delegation</a></li></ul></li><li><a href="#getting-started-example" title="Getting started example">Getting started example</a></li><li><a href="#advanced-use" title="Advanced use">Advanced use</a><ul><li><a href="#bypassing-dispatch" title="Bypassing `Dispatch`">Bypassing <code>Dispatch</code></a></li><li><a href="#interaction-with-ffi" title="Interaction with FFI">Interaction with FFI</a></li></ul></li></ul><h3><a href="#modules">Crate Items</a></h3><ul class="block"><li><a href="#modules" title="Modules">Modules</a></li><li><a href="#macros" title="Macros">Macros</a></li><li><a href="#structs" title="Structs">Structs</a></li><li><a href="#enums" title="Enums">Enums</a></li><li><a href="#traits" title="Traits">Traits</a></li></ul></section><div id="rustdoc-modnav"><h2><a href="../index.html">In cosmic::<wbr>cctk::<wbr>sctk::<wbr>reexports</a></h2></div></div></nav><div class="sidebar-resizer" title="Drag to resize sidebar"></div><main><div class="width-limiter"><rustdoc-search></rustdoc-search><section id="main-content" class="content"><div class="main-heading"><div class="rustdoc-breadcrumbs"><a href="../../../../index.html">cosmic</a>::<wbr><a href="../../../index.html">cctk</a>::<wbr><a href="../../index.html">sctk</a>::<wbr><a href="../index.html">reexports</a></div><h1>Crate <span>client</span><button id="copy-path" title="Copy item path to clipboard">Copy item path</button></h1><rustdoc-toolbar></rustdoc-toolbar><span class="sub-heading"></span></div><span class="item-info"><div class="stab portability">Available on <strong>crate feature <code>wayland</code> and Linux</strong> only.</div></span><details class="toggle top-doc" open><summary class="hideme"><span>Expand description</span></summary><div class="docblock"><p>Interface for interacting with the Wayland protocol, client-side.</p>
<h3 id="general-concepts"><a class="doc-anchor" href="#general-concepts">§</a>General concepts</h3>
<p>This crate is structured around four main objects: the <a href="struct.Connection.html" title="struct cosmic::cctk::sctk::reexports::client::Connection"><code>Connection</code></a> and <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> structs,
proxies (objects implementing the <a href="trait.Proxy.html" title="trait cosmic::cctk::sctk::reexports::client::Proxy"><code>Proxy</code></a> trait), and the <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> trait.</p>
<p>The <a href="struct.Connection.html" title="struct cosmic::cctk::sctk::reexports::client::Connection"><code>Connection</code></a> is the heart of this crate. It represents your connection to the Wayland server, and
youll generally initialize it using the <a href="struct.Connection.html#method.connect_to_env" title="associated function cosmic::cctk::sctk::reexports::client::Connection::connect_to_env"><code>Connection::connect_to_env()</code></a> method, which will
attempt to open a Wayland connection following the configuration specified by the ! environment.</p>
<p>Once you have a <a href="struct.Connection.html" title="struct cosmic::cctk::sctk::reexports::client::Connection"><code>Connection</code></a>, you can create an <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> from it. This <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> will take
care of processing events from the Wayland server and delivering them to your processing logic, in the form
of a state struct with several <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> implementations (see below).</p>
<p>Each of the Wayland objects you can manipulate is represented by a struct implementing the <a href="trait.Proxy.html" title="trait cosmic::cctk::sctk::reexports::client::Proxy"><code>Proxy</code></a>
trait. Those structs are automatically generated from the wayland XML protocol specification. This crate
provides the types generated from the core protocol in the <a href="protocol/index.html" title="mod cosmic::cctk::sctk::reexports::client::protocol"><code>protocol</code></a> module. For other standard
protocols, see the <code>wayland-protocols</code> crate.</p>
<h3 id="event-dispatching"><a class="doc-anchor" href="#event-dispatching">§</a>Event dispatching</h3>
<p>The core event dispatching logic provided by this crate is built around the <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> struct. In
this paradigm, receiving and processing events is a two-step process:</p>
<ul>
<li>First, events are read from the Wayland socket. For each event, the backend figures out which <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a>
manages it, and enqueues the event in an internal buffer of that queue.</li>
<li>Then, the <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> empties its internal buffer by sequentially invoking the appropriate
<a href="trait.Dispatch.html#tymethod.event" title="associated function cosmic::cctk::sctk::reexports::client::Dispatch::event"><code>Dispatch::event()</code></a> method on the <code>State</code> value that was provided to it.</li>
</ul>
<p>The main goal of this structure is to make your <code>State</code> accessible without synchronization to most of
your event-processing logic, to reduce the plumbing costs. See <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a>s documentation for
explanations of how to use it to drive your event loop, and when and how to use multiple
event queues in your app.</p>
<h4 id="the-dispatch-trait-and-dispatch-delegation"><a class="doc-anchor" href="#the-dispatch-trait-and-dispatch-delegation">§</a>The <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> trait and dispatch delegation</h4>
<p>In this paradigm, your <code>State</code> needs to implement <code>Dispatch&lt;O, _&gt;</code> for every Wayland object <code>O</code> it needs to
process events for. This is ensured by the fact that, whenever creating an object using the methods on
an other object, you need to pass a <a href="struct.QueueHandle.html" title="struct cosmic::cctk::sctk::reexports::client::QueueHandle"><code>QueueHandle&lt;State&gt;</code></a> from the <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> that will be
managing the newly created object.</p>
<p>However, implementing all those traits on your own is a lot of (often uninteresting) work. To make this
easier a composition mechanism is provided using the <a href="macro.delegate_dispatch.html" title="macro cosmic::cctk::sctk::reexports::client::delegate_dispatch"><code>delegate_dispatch!</code></a> macro. This way, another
library (such as Smithays Client Toolkit) can provide generic <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> implementations that you
can reuse in your own app by delegating those objects to that provided implementation. See the
documentation of those traits and macro for details.</p>
<h3 id="getting-started-example"><a class="doc-anchor" href="#getting-started-example">§</a>Getting started example</h3>
<p>As an overview of how this crate is used, here is a commented example of a program that connects to the
Wayland server and lists the globals this server advertised through the <code>wl_registry</code>:</p>
<div class="example-wrap"><pre class="rust rust-example-rendered"><code><span class="kw">use </span>wayland_client::{protocol::wl_registry, Connection, Dispatch, QueueHandle};
<span class="comment">// This struct represents the state of our app. This simple app does not
// need any state, but this type still supports the `Dispatch` implementations.
</span><span class="kw">struct </span>AppData;
<span class="comment">// Implement `Dispatch&lt;WlRegistry, ()&gt; for our state. This provides the logic
// to be able to process events for the wl_registry interface.
//
// The second type parameter is the user-data of our implementation. It is a
// mechanism that allows you to associate a value to each particular Wayland
// object, and allow different dispatching logic depending on the type of the
// associated value.
//
// In this example, we just use () as we don't have any value to associate. See
// the `Dispatch` documentation for more details about this.
</span><span class="kw">impl </span>Dispatch&lt;wl_registry::WlRegistry, ()&gt; <span class="kw">for </span>AppData {
<span class="kw">fn </span>event(
_state: <span class="kw-2">&amp;mut </span><span class="self">Self</span>,
<span class="kw">_</span>: <span class="kw-2">&amp;</span>wl_registry::WlRegistry,
event: wl_registry::Event,
<span class="kw">_</span>: <span class="kw-2">&amp;</span>(),
<span class="kw">_</span>: <span class="kw-2">&amp;</span>Connection,
<span class="kw">_</span>: <span class="kw-2">&amp;</span>QueueHandle&lt;AppData&gt;,
) {
<span class="comment">// When receiving events from the wl_registry, we are only interested in the
// `global` event, which signals a new available global.
// When receiving this event, we just print its characteristics in this example.
</span><span class="kw">if let </span>wl_registry::Event::Global { name, interface, version } = event {
<span class="macro">println!</span>(<span class="string">"[{}] {} (v{})"</span>, name, interface, version);
}
}
}
<span class="comment">// The main function of our program
</span><span class="kw">fn </span>main() {
<span class="comment">// Create a Wayland connection by connecting to the server through the
// environment-provided configuration.
</span><span class="kw">let </span>conn = Connection::connect_to_env().unwrap();
<span class="comment">// Retrieve the WlDisplay Wayland object from the connection. This object is
// the starting point of any Wayland program, from which all other objects will
// be created.
</span><span class="kw">let </span>display = conn.display();
<span class="comment">// Create an event queue for our event processing
</span><span class="kw">let </span><span class="kw-2">mut </span>event_queue = conn.new_event_queue();
<span class="comment">// And get its handle to associate new objects to it
</span><span class="kw">let </span>qh = event_queue.handle();
<span class="comment">// Create a wl_registry object by sending the wl_display.get_registry request.
// This method takes two arguments: a handle to the queue that the newly created
// wl_registry will be assigned to, and the user-data that should be associated
// with this registry (here it is () as we don't need user-data).
</span><span class="kw">let </span>_registry = display.get_registry(<span class="kw-2">&amp;</span>qh, ());
<span class="comment">// At this point everything is ready, and we just need to wait to receive the events
// from the wl_registry. Our callback will print the advertised globals.
</span><span class="macro">println!</span>(<span class="string">"Advertised globals:"</span>);
<span class="comment">// To actually receive the events, we invoke the `roundtrip` method. This method
// is special and you will generally only invoke it during the setup of your program:
// it will block until the server has received and processed all the messages you've
// sent up to now.
//
// In our case, that means it'll block until the server has received our
// wl_display.get_registry request, and as a reaction has sent us a batch of
// wl_registry.global events.
//
// `roundtrip` will then empty the internal buffer of the queue it has been invoked
// on, and thus invoke our `Dispatch` implementation that prints the list of advertised
// globals.
</span>event_queue.roundtrip(<span class="kw-2">&amp;mut </span>AppData).unwrap();
}</code></pre></div>
<h3 id="advanced-use"><a class="doc-anchor" href="#advanced-use">§</a>Advanced use</h3><h4 id="bypassing-dispatch"><a class="doc-anchor" href="#bypassing-dispatch">§</a>Bypassing <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a></h4>
<p>It may be that for some of your objects, handling them via the <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a> is impractical. For example,
if processing the events from those objects doesnt require accessing some global state, and/or you need to
handle them in a context where cranking an event loop is impractical.</p>
<p>In those contexts, this crate also provides some escape hatches to directly interface with the low-level
APIs from <code>wayland-backend</code>, allowing you to register callbacks for those objects that will be invoked
whenever they receive an event and <em>any</em> event queue from the program is being dispatched. Those
callbacks are more constrained: they dont get a <code>&amp;mut State</code> reference, and must be threadsafe. See
<a href="trait.Proxy.html#tymethod.send_constructor" title="method cosmic::cctk::sctk::reexports::client::Proxy::send_constructor"><code>Proxy::send_constructor()</code></a> and <a href="backend/trait.ObjectData.html" title="trait cosmic::cctk::sctk::reexports::client::backend::ObjectData"><code>ObjectData</code></a> for details about how to
assign such callbacks to objects.</p>
<h4 id="interaction-with-ffi"><a class="doc-anchor" href="#interaction-with-ffi">§</a>Interaction with FFI</h4>
<p>It can happen that youll need to interact with Wayland states accross FFI. A typical example would be if
you need to use the <a href="https://docs.rs/raw-window-handle/"><code>raw-window-handle</code></a> crate.</p>
<p>In this case, youll need enable the <code>system</code> feature to use the <code>libwayland</code> backend of
<code>wayland-backend</code>.</p>
<ul>
<li>If you need to send pointers to FFI, you can retrive the <code>*mut wl_proxy</code> pointers from the proxies by
first getting the <a href="backend/struct.ObjectId.html" title="struct cosmic::cctk::sctk::reexports::client::backend::ObjectId"><code>ObjectId</code></a> using the <a href="trait.Proxy.html#tymethod.id" title="method cosmic::cctk::sctk::reexports::client::Proxy::id"><code>Proxy::id()</code></a> method, and then
using the <a href="backend/struct.ObjectId.html#method.as_ptr" title="method cosmic::cctk::sctk::reexports::client::backend::ObjectId::as_ptr"><code>ObjectId::as_ptr()</code></a> method.</li>
</ul>
</div></details><h2 id="modules" class="section-header">Modules<a href="#modules" class="anchor">§</a></h2><dl class="item-table"><dt><a class="mod" href="backend/index.html" title="mod cosmic::cctk::sctk::reexports::client::backend">backend</a></dt><dd>Backend reexports</dd><dt><a class="mod" href="globals/index.html" title="mod cosmic::cctk::sctk::reexports::client::globals">globals</a></dt><dd>Helpers for handling the initialization of an app</dd><dt><a class="mod" href="protocol/index.html" title="mod cosmic::cctk::sctk::reexports::client::protocol">protocol</a></dt><dd>Generated protocol definitions</dd></dl><h2 id="macros" class="section-header">Macros<a href="#macros" class="anchor">§</a></h2><dl class="item-table"><dt><a class="macro" href="macro.delegate_dispatch.html" title="macro cosmic::cctk::sctk::reexports::client::delegate_dispatch">delegate_<wbr>dispatch</a></dt><dd>A helper macro which delegates a set of <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> implementations for proxies to some other type which
provides a generic <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> implementation.</dd><dt><a class="macro" href="macro.delegate_noop.html" title="macro cosmic::cctk::sctk::reexports::client::delegate_noop">delegate_<wbr>noop</a></dt><dd>A helper macro which delegates a set of <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a> implementations for proxies to a static handler.</dd><dt><a class="macro" href="macro.event_created_child.html" title="macro cosmic::cctk::sctk::reexports::client::event_created_child">event_<wbr>created_<wbr>child</a></dt><dd>Macro used to override <a href="trait.Dispatch.html#method.event_created_child" title="associated function cosmic::cctk::sctk::reexports::client::Dispatch::event_created_child"><code>Dispatch::event_created_child()</code></a></dd></dl><h2 id="structs" class="section-header">Structs<a href="#structs" class="anchor">§</a></h2><dl class="item-table"><dt><a class="struct" href="struct.Connection.html" title="struct cosmic::cctk::sctk::reexports::client::Connection">Connection</a></dt><dd>The Wayland connection</dd><dt><a class="struct" href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue">Event<wbr>Queue</a></dt><dd>An event queue</dd><dt><a class="struct" href="struct.QueueFreezeGuard.html" title="struct cosmic::cctk::sctk::reexports::client::QueueFreezeGuard">Queue<wbr>Freeze<wbr>Guard</a></dt><dd>A handle that temporarily pauses event processing on an <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a>.</dd><dt><a class="struct" href="struct.QueueHandle.html" title="struct cosmic::cctk::sctk::reexports::client::QueueHandle">Queue<wbr>Handle</a></dt><dd>A handle representing an <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a>, used to assign objects upon creation.</dd><dt><a class="struct" href="struct.QueueProxyData.html" title="struct cosmic::cctk::sctk::reexports::client::QueueProxyData">Queue<wbr>Proxy<wbr>Data</a></dt><dd>The <a href="backend/trait.ObjectData.html" title="trait cosmic::cctk::sctk::reexports::client::backend::ObjectData"><code>ObjectData</code></a> implementation used by Wayland proxies, integrating with <a href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch"><code>Dispatch</code></a></dd><dt><a class="struct" href="struct.Weak.html" title="struct cosmic::cctk::sctk::reexports::client::Weak">Weak</a></dt><dd>A weak handle to a Wayland object</dd></dl><h2 id="enums" class="section-header">Enums<a href="#enums" class="anchor">§</a></h2><dl class="item-table"><dt><a class="enum" href="enum.ConnectError.html" title="enum cosmic::cctk::sctk::reexports::client::ConnectError">Connect<wbr>Error</a></dt><dd>An error when trying to establish a Wayland connection.</dd><dt><a class="enum" href="enum.DispatchError.html" title="enum cosmic::cctk::sctk::reexports::client::DispatchError">Dispatch<wbr>Error</a></dt><dd>Wayland dispatching error</dd><dt><a class="enum" href="enum.WEnum.html" title="enum cosmic::cctk::sctk::reexports::client::WEnum">WEnum</a></dt><dd>An enum value in the protocol.</dd></dl><h2 id="traits" class="section-header">Traits<a href="#traits" class="anchor">§</a></h2><dl class="item-table"><dt><a class="trait" href="trait.Dispatch.html" title="trait cosmic::cctk::sctk::reexports::client::Dispatch">Dispatch</a></dt><dd>A trait for handlers of proxies events delivered to an <a href="struct.EventQueue.html" title="struct cosmic::cctk::sctk::reexports::client::EventQueue"><code>EventQueue</code></a>.</dd><dt><a class="trait" href="trait.Proxy.html" title="trait cosmic::cctk::sctk::reexports::client::Proxy">Proxy</a></dt><dd>Trait representing a Wayland interface</dd></dl></section></div></main></body></html>