lcd script

[JarredAwesome]

Hey everyone,

I'm working on a function that helps phrase the values for a 16x2 char lcd. every 5 seconds the screen changes to a different 'page'.
at the moment it does what I need, but I feel there is a cleaner way to do what I want


Here is the script:

def __value(self, data, Session, screenNum=0, line=1):
        now = display.datetime.now()
        r = None

#phrase line 1                
        if line == 1:
#phrase line 1 screen 2
            if screenNum == 1:
                r = "\x07\x03"+self.__PiTemp()
#phrase line 1 screen 1, or default if none valid screen number is given
            if r == None: # screen 0 / default
                r =  "Time: %s" %now.strftime("%H:%M:%S") #screen 0
            screenMax = 1

        else: #line 2
#phrase line 2 screen 2
            if screenNum == 1:
                #r =  self.__co2Levels(resp['/api/equipment/9'])
                r =  self.__co2Levels('22')
#phrase line 2 screen 3
            if screenNum == 2:
                r =  self.__equipmentStatus1()
#phrase line 2 screen 4
            if screenNum == 3:
                r =  self.__equipmentStatus2()
#phrase line 2 screen 1, or default if none valid screen number is given
            if r == None: # screen 0 / default
                r =  "H20\x03"+self.__tankTemp(data)
            screenMax = 3

        return [r, (screenMax < screenNum)]

above you can see it takes the line and page number (represented by screenNum, line respectively), and returns the phrased script along with a boolean value showing if the page number exists. Which is great.

However, if I want to add more pages to a screen, I have to add another 'if' statement, and readjust the screenMax variables.

I would like to find a more elegant way, that is able to calculate the "screenMax" on its own, and doesn't need to add an additional 'if' statement to the code.



Anyone have any ideas?

[JarredAwesome]

This is what I came up with.

Hopefully someone can use this to help themselves out

I use replace and getattr. I put the name of the functions I need into square brackets

    def __value(self, Session, screenNum=0, line=1):

        if line == 1:
            lineVal = ("Time: [time]","\x07\x03[PiTemp]")
        else:
            lineVal = ("H20\x03[tankTemp]", "Co2: [co2Levels]","[equipmentStatus1]","[equipmentStatus2]")

        funcs=('[time]','[PiTemp]','[tankTemp]','[co2Levels]','[equipmentStatus1]','[equipmentStatus2]')
        try:
            r = lineVal[screenNum]
        except Exception:
            r = lineVal[0]

        for i in funcs:
            if i in r:
                func = getattr(self, i[1:-1])
                r = r.replace(i, func(self))

        return [r, ((len(lineVal)-1) < screenNum)]

[Larz60+]

A different approach (but I may like JarredAwsome's better, haven't decided yet)
Everything after # ........... is for testing only and can be removed after trying as standalone

please note, I also removed name mangling (underscores), add back if needed

class Dummy:
    def dvalue(self, data, Session, screenNum=0, line=1):
        rscreen = {
            1: self.rfunc1,
            2: self.rfunc2,
            3: self.rfunc3,
            None: self.rfuncnone
        }

        # following was commented out as display not defined
        # now = display.datetime.now()
        r = None
        r = rscreen[screenNum](data, Session, screenNum, line)

    def rfunc1(self, data, Session, screenNum, line):
        if line == 1:
            return f"\x07\x03{self.PiTemp()}"
        else:
            return self.co2Levels('22')

    def rfunc2(self, data, Session, screenNum, line):
        return self.equipmentStatus1()
    
    def rfunc3(self, data, Session, screenNum, line):
        return self.equipmentStatus2()
    
    def rfuncnone(self, data, Session, screenNum, line):
        return "H20\x03"+self.tankTemp(data)

# ...........
# Dummy sub functions:
# for testing only remove after assuring all is working well:
    def PiTemp(self):
        return "SomeValue"

    def co2Levels(self, value):
        print(f"executing co2Levels value: {value}")
    
    def equipmentStatus1(self):
        print(f"executing equipmentStatus1")
    
    def equipmentStatus2(self):
        print(f"executing equipmentStatus2")

    def tankTemp(self, data):
        print(f"executing tankTemp data: {data}")

def testit():
    dum = Dummy()

    data = [1, 2, 3, 4]
    Session = None # this was not used

    for line in range(2):
        for screenNum in range(1, 4):
            print(f"\nTest for:\n  data: {data}\n   Session: {Session}" \
                f"\n   screenNum: {screenNum}\n   line: {line}")
            dum.dvalue(data, Session, screenNum, line)


if __name__ == '__main__':
    testit()