examples: add GstPlay example

examples/Cargo.toml

@@ -18,6 +18,7 @@ gst-audio = { package = "gstreamer-audio", path = "../gstreamer-audio" }
 gst-base = { package = "gstreamer-base", path = "../gstreamer-base" }
 gst-video = { package = "gstreamer-video", path = "../gstreamer-video" }
 gst-pbutils = { package = "gstreamer-pbutils", path = "../gstreamer-pbutils" }
+gst-play = { package = "gstreamer-play", path = "../gstreamer-play", optional = true }
 gst-player = { package = "gstreamer-player", path = "../gstreamer-player", optional = true }
 ges = { package = "gstreamer-editing-services", path = "../gstreamer-editing-services", optional = true }
 gst-sdp = { package = "gstreamer-sdp", path = "../gstreamer-sdp", optional = true }
@@ -107,6 +108,10 @@ name = "transmux"
 [[bin]]
 name = "pad_probes"
 
+[[bin]]
+name = "play"
+required-features = ["gst-play"]
+
 [[bin]]
 name = "playbin"
 

examples/src/bin/play.rs

@@ -0,0 +1,62 @@
+// This example shows how to use the GstPlay API.
+// The GstPlay API is a convenience API to allow implement playback applications
+// without having to write too much code.
+// Most of the tasks a play needs to support (such as seeking and switching
+// audio / subtitle streams or changing the volume) are all supported by simple
+// one-line function calls on the GstPlay.
+
+use std::env;
+
+use anyhow::Error;
+
+#[path = "../examples-common.rs"]
+mod examples_common;
+
+use gst_play::{Play, PlayMessage, PlayVideoRenderer};
+
+fn main_loop(uri: &str) -> Result<(), Error> {
+    gst::init()?;
+
+    let play = Play::new(PlayVideoRenderer::NONE);
+    play.set_uri(Some(uri));
+    play.play();
+
+    let mut result = Ok(());
+    for msg in play.message_bus().iter_timed(gst::ClockTime::NONE) {
+        match PlayMessage::parse(&msg) {
+            Ok(PlayMessage::EndOfStream) => {
+                play.stop();
+                break;
+            }
+            Ok(PlayMessage::Error { error, details: _ }) => {
+                result = Err(error);
+                play.stop();
+                break;
+            }
+            Ok(_) => (),
+            Err(_) => unreachable!(),
+        }
+    }
+    result.map_err(|e| e.into())
+}
+
+fn example_main() {
+    let args: Vec<_> = env::args().collect();
+    let uri: &str = if args.len() == 2 {
+        args[1].as_ref()
+    } else {
+        println!("Usage: play uri");
+        std::process::exit(-1)
+    };
+
+    match main_loop(uri) {
+        Ok(r) => r,
+        Err(e) => eprintln!("Error! {}", e),
+    }
+}
+
+fn main() {
+    // tutorials_common::run is only required to set up the application environment on macOS
+    // (but not necessary in normal Cocoa applications where this is set up automatically)
+    examples_common::run(example_main);
+}