Requests a hint about the valid range of values for the state of the
named action within action_group.
If NULL is returned it either means that the action is not stateful
or that there is no hint about the valid range of values for the
state of the action.
If a GVariant array is returned then each item in the array is a
possible value for the state. If a GVariant pair (ie: two-tuple) is
returned then the tuple specifies the inclusive lower and upper bound
of valid values for the state.
In any case, the information is merely a hint. It may be possible to
have a state value outside of the hinted range and setting a value
within the range may fail.
The return value (if non-NULL) should be freed with
g_variant_unref() when it is no longer required.
Since 2.28
Requests a hint about the valid range of values for the state of the named action within action_group. If NULL is returned it either means that the action is not stateful or that there is no hint about the valid range of values for the state of the action. If a GVariant array is returned then each item in the array is a possible value for the state. If a GVariant pair (ie: two-tuple) is returned then the tuple specifies the inclusive lower and upper bound of valid values for the state. In any case, the information is merely a hint. It may be possible to have a state value outside of the hinted range and setting a value within the range may fail. The return value (if non-NULL) should be freed with g_variant_unref() when it is no longer required. Since 2.28