Added setters to CallbackFlag's bits (#255)

Author: mattgwwalker

sounddevice.py

@@ -1844,6 +1844,19 @@ class CallbackFlags(object):
     >>> errors.input_overflow
     True
 
+    The values may also be set and cleared by the user:
+
+    >>> import sounddevice as sd
+    >>> cf = sd.CallbackFlags()
+    >>> cf
+    <sounddevice.CallbackFlags: no flags set>
+    >>> cf.input_underflow = True
+    >>> cf
+    <sounddevice.CallbackFlags: input underflow>
+    >>> cf.input_underflow = False
+    >>> cf
+    <sounddevice.CallbackFlags: no flags set>
+
     """
 
     __slots__ = '_flags'
@@ -1886,6 +1899,10 @@ def input_underflow(self):
         """
         return self._hasflag(_lib.paInputUnderflow)
 
+    @input_underflow.setter
+    def input_underflow(self, value):
+        self._updateflag(_lib.paInputUnderflow, value)
+
     @property
     def input_overflow(self):
         """Input overflow.
@@ -1903,6 +1920,10 @@ def input_overflow(self):
         """
         return self._hasflag(_lib.paInputOverflow)
 
+    @input_overflow.setter
+    def input_overflow(self, value):
+        self._updateflag(_lib.paInputOverflow, value)
+
     @property
     def output_underflow(self):
         """Output underflow.
@@ -1916,6 +1937,10 @@ def output_underflow(self):
         """
         return self._hasflag(_lib.paOutputUnderflow)
 
+    @output_underflow.setter
+    def output_underflow(self, value):
+        self._updateflag(_lib.paOutputUnderflow, value)
+
     @property
     def output_overflow(self):
         """Output overflow.
@@ -1930,6 +1955,10 @@ def output_overflow(self):
         """
         return self._hasflag(_lib.paOutputOverflow)
 
+    @output_overflow.setter
+    def output_overflow(self, value):
+        self._updateflag(_lib.paOutputOverflow, value)
+
     @property
     def priming_output(self):
         """Priming output.
@@ -1949,6 +1978,13 @@ def _hasflag(self, flag):
         """Check a given flag."""
         return bool(self._flags & flag)
 
+    def _updateflag(self, flag, value):
+        """Set/clear a given flag."""
+        if value:
+            self._flags |= flag
+        else:
+            self._flags &= ~flag
+
 
 class _InputOutputPair(object):
     """Parameter pairs for device, channels, dtype and latency."""