26 lines
631 B
Python
26 lines
631 B
Python
from ngSkinTools2.api.python_compatibility import Object
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from ngSkinTools2.signal import Signal
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class Undefined(Object):
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pass
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class ObservableValue(Object):
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def __init__(self, default_value=Undefined):
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self.value = default_value
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self.changed = Signal("observable value")
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def set(self, value):
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self.value = value
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self.changed.emit()
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def __call__(self, default=Undefined, *args, **kwargs):
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if self.value != Undefined:
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return self.value
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if default != Undefined:
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return default
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raise Exception("在设置之前使用可观察值")
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