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/** \page page_tutorial6 Tutorial - Part 6: Binding objects
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\ref page_tutorial5 | \ref page_tutorial "Index"
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In this tutorial we show how to bind to an object so that we can
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receive events and call methods on the object.
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Let take a look at the following application to start.
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\snippet tutorial6.c code
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To compile the simple test application, copy it into a tutorial6.c file and
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use:
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gcc -Wall tutorial6.c -o tutorial6 $(pkg-config --cflags --libs libpipewire-0.3)
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Most of this is the same as \ref page_tutorial2 where we simply
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enumerated all objects on the server. Instead of just printing the object
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id and some other properties, in this example we also bind to the object.
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We use the `pw_registry_bind()` method on our registry object like this:
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\snippet tutorial6.c registry_event_global
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We bind to the first client object that we see. This gives us a pointer
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to a `struct pw_proxy` that we can also cast to a `struct pw_client`.
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On the proxy we can call methods and listen for events. PipeWire will
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automatically serialize the method calls and events between client and
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server for us.
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We can now listen for events by adding a listener. We're going to
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listen to the info event on the client object that is emitted right
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after we bind to it or when it changes. This is not very different
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from the registry listener we added before:
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\snippet tutorial6.c client_info
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\code{.c}
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static void registry_event_global(void *_data, uint32_t id,
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uint32_t permissions, const char *type,
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uint32_t version, const struct spa_dict *props)
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{
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/* ... */
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pw_client_add_listener(data->client,
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&data->client_listener,
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&client_events, data);
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/* ... */
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}
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\endcode
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2020-07-22 18:54:06 +00:00
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We're also quitting the mainloop after we get the info to nicely stop
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our tutorial application.
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When we stop the application, don't forget to destroy all proxies that
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you created. Otherwise, they will be leaked:
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\code{.c}
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/* ... */
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pw_proxy_destroy((struct pw_proxy *)data.client);
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/* ... */
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return 0;
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}
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\endcode
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\ref page_tutorial5 | \ref page_tutorial "Index"
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*/
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