多用，多看
要求
写一个可以给人搭配不同的服饰的系统
思路
Iter1 初始草稿
#!/usr/bin/python
# coding:utf-8
class Person:
def __init__(self, name):
self.name = name
def wearTShirts(self):
print "大T恤",
def wearBigTrouser(self):
print "垮裤",
def wearSneakers(self):
print "破球鞋",
def wearSuit(self):
print "西装",
def wearTie(self):
print "领带",
def wearLeatherShoes(self):
print "皮鞋",
def show(self):
print "装扮的%s" %(self.name), "\n"
if __name__ == "__main__":
xc = Person("小菜")
print "第一种装扮"
xc.wearTShirts()
xc.wearBigTrouser()
xc.wearSneakers()
xc.show()
print "第二种装扮"
xc.wearSuit()
xc.wearTie()
xc.wearLeatherShoes()
xc.show()
问题：
- 如果需要增加一种装扮，如超人装扮，如何做？
开放-封闭原则：软件实体（类，模块，函数）应当可以扩展，但是不可修改。
Iter2 松耦合
#!/usr/bin/python
# coding:utf-8
class Person:
def __init__(self, name):
self.name = name
def show(self):
print "装扮的%s" % (self.name)
class Fienry:
def show(self):
pass
class TShirts(Fienry):
def show(self):
print "大T恤",
class BigTrouser(Fienry):
def show(self):
print "垮裤",
class Sneakers(Fienry):
def show(self):
print "破球鞋",
class Suit(Fienry):
def show(self):
print "西装",
class Tie(Fienry):
def show(self):
print "领带",
class LeatherShoes(Fienry):
def show(self):
print "皮鞋",
if __name__ == "__main__":
xc = Person("小菜")
print "第一种装扮"
dtx = TShirts()
kk = BigTrouser()
pqx = Sneakers()
dtx.show()
kk.show()
pqx.show()
xc.show()
print "第二种装扮"
xz = Suit()
ld = Tie()
px = LeatherShoes()
xz.show()
ld.show()
px.show()
xc.show()
问题：
- 怎么才能将所需的功能按照正确的顺序串联起来进行控制？
Iter3 装饰模式
装饰模式：动态地给一个对象添加一些额外的职责，就增加功能来说，装饰模式比生成子类更为灵活。
#!/usr/python
#encoding:utf-8
class Component:
def operation(self):
return
class ConcreteComponent(Component):
def operation(self):
print "具体对象的操作"
class Decorator(Component):
def __init__(self):
self.component = None
def setcomponent(self, component):
self.component = component
def operation(self):
if self.component:
self.component.operation()
class ConcreteDecoratorA(Decorator):
def operation(self):
self.component.operation()
print "具体装饰对象A的操作"
class ConcreteDecoratorB(Decorator):
def operation(self):
self.component.operation()
print "具体装饰对象B的操作"
if __name__ == "__main__":
c = ConcreteComponent()
d1 = ConcreteDecoratorA()
d2 = ConcreteDecoratorB()
d1.setcomponent(c)
d2.setcomponent(d1)
d2.operation()
Iter4 利用装饰模式来实现
#!/usr/bin/python
# coding:utf-8
class Person:
def __init__(self, name):
self.name = name
def show(self):
print "装扮好的%s" % (self.name)
class Fienry(Person):
def __init__(self):
self.component = None
def setcomponent(self, component):
self.component = component
def show(self):
pass
class TShirts(Fienry):
def show(self):
print "大T恤"
self.component.show()
class BigTrouser(Fienry):
def show(self):
print "垮裤"
self.component.show()
class Sneakers(Fienry):
def show(self):
print "破球鞋"
self.component.show()
class Suit(Fienry):
def show(self):
print "西装"
self.component.show()
class Tie(Fienry):
def show(self):
print "领带"
self.component.show()
class LeatherShoes(Fienry):
def show(self):
print "皮鞋"
self.component.show()
if __name__ == "__main__":
xc = Person("小菜")
print "第一种装扮"
dtx = TShirts()
kk = BigTrouser()
pqx = Sneakers()
dtx.setcomponent(xc)
kk.setcomponent(dtx)
pqx.setcomponent(kk)
pqx.show()
print ""
print "第二种装扮"
xz = Suit()
ld = Tie()
px = LeatherShoes()
xz.setcomponent(xc)
ld.setcomponent(xz)
px.setcomponent(ld)
px.show()
装饰模式是为已有的功能动态地添加更多功能的一种方式。
有效地把类的核心职责和装饰功能区分开，并且可以去除相关类中重复的装饰逻辑。
UML图
Decorator Pattern
Fienry Decorator
细碎python
- abstract method
- 装饰器 装饰模式
PS
好像开始慢慢上手了
