move callbacks/observer examples into examples/events/

examples/events/callbacks/__main__.py

@@ -0,0 +1,53 @@
+import logging
+import time
+
+import voicemeeterlib
+
+logging.basicConfig(level=logging.INFO)
+
+
+class App:
+    def __init__(self, vm):
+        self._vm = vm
+        # register the callbacks for each event
+        self._vm.observer.add(
+            [self.on_pdirty, self.on_mdirty, self.on_ldirty, self.on_midi]
+        )
+
+    def __enter__(self):
+        self._vm.init_thread()
+        return self
+
+    def __exit__(self, exc_type, exc_value, traceback):
+        self._vm.end_thread()
+
+    def on_pdirty(self):
+        print('pdirty!')
+
+    def on_mdirty(self):
+        print('mdirty!')
+
+    def on_ldirty(self):
+        for bus in self._vm.bus:
+            if bus.levels.isdirty:
+                print(bus, bus.levels.all)
+
+    def on_midi(self):
+        current = self._vm.midi.current
+        print(f'Value of midi button {current} is {self._vm.midi.get(current)}')
+
+
+def main():
+    KIND_ID = 'banana'
+
+    with voicemeeterlib.api(KIND_ID) as vm:
+        with App(vm):
+            for i in range(5, 0, -1):
+                print(f'events start in {i} seconds')
+                time.sleep(1)
+            vm.event.add(['pdirty', 'ldirty', 'midi', 'mdirty'])
+            time.sleep(30)
+
+
+if __name__ == '__main__':
+    main()