7. Temperature converter3

7.1. Multi Temperature converter

Make an new app that converts between F, C and K all at once.

Working app at: https://pc-temperature-converter-3.anvil.app

See gif to see it in action.

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7.2. Design

Name the From buttons: from_F, from_C and from_K.

Name the convert buttons: convertF, convertC and convertK.

Name the input temperature textboxes: TF, TC and TK.

Layout the components:

Search online for a temperature icon to use. Save it. Edit it. For use as an app logo, add it to the Assets, via the 3 vertical dots Add Assets and Upload File button. Add the icon to the convert buttons using the upload an image button in the properties panel icon section.

Click on From F, From C, or From K to hide the other convert buttons, only showing the associated convert button.

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7.3. Code

Tasks

1. Write code to control the visibility of the Convert buttons and replace the temperature scale label to indicate which is being used for the conversion.

2. Write code to carry out the conversions for each temperature scale.

3. Write the full code.

Q1

Write code to control the visibility of the Convert buttons and replace the temperature scale label to indicate which is being used for the conversion.

from ._anvil_designer import Form1Template
from anvil import *
import anvil.tables as tables
import anvil.tables.query as q
from anvil.tables import app_tables

class Form1(Form1Template):

    def __init__(self, **properties):
        # Set Form properties and Data Bindings.
        self.init_components(**properties)
        # start with from F
        self.from_F_click()

    def from_F_click(self, **event_args):
        self.TF_label.text = "from Fahrenheit"
        self.TC_label.text = "Celcius"
        self.TK_label.text = "Kelvin"
        self.convertF.visible = True
        self.convertC.visible = False
        self.convertK.visible = False
        self.TF.select()

    def from_C_click(self, **event_args):
        self.TF_label.text = "Fahrenheit"
        self.TC_label.text = "from Celcius"
        self.TK_label.text = "Kelvin"
        self.convertF.visible = False
        self.convertC.visible = True
        self.convertK.visible = False
        self.TC.select()

    def from_K_click(self, **event_args):
        self.TF_label.text = "Fahrenheit"
        self.TC_label.text = "Celcius"
        self.TK_label.text = "from Kelvin"
        self.convertF.visible = False
        self.convertC.visible = False
        self.convertK.visible = True
        self.TK.select()

Q2

Write code to carry out the conversions for each temperature scale.

from ._anvil_designer import Form1Template
from anvil import *
import anvil.tables as tables
import anvil.tables.query as q
from anvil.tables import app_tables

class Form1(Form1Template):

    def convertF_click(self, **event_args):
        self.f_calculate()

    def convertC_click(self, **event_args):
        self.c_calculate()

    def convertK_click(self, **event_args):
        self.k_calculate()

    def f_calculate(self):
        try:
            fahrenheit = self.TF.text
            fahrenheit = float(fahrenheit)
            celcius = (fahrenheit - 32) / 1.8
            self.TC.text = f'{celcius:.1f}'
            kelvin = celcius + 273.15
            self.TK.text = f'{kelvin:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None

    def c_calculate(self):
        try:
            celcius = self.TC.text
            celcius = float(celcius)
            fahrenheit = (celcius * 1.8) + 32
            self.TF.text =  f'{fahrenheit:.1f}'
            kelvin = celcius + 273.15
            self.TK.text = f'{kelvin:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None

    def k_calculate(self):
        try:
            kelvin = self.TK.text
            kelvin = float(kelvin)
            celcius = kelvin - 273.15
            self.TC.text = f'{celcius:.1f}'
            fahrenheit = (celcius * 1.8) + 32
            self.TF.text =  f'{fahrenheit:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None

Q3

Write the full code.

from ._anvil_designer import Form1Template
from anvil import *
import anvil.tables as tables
import anvil.tables.query as q
from anvil.tables import app_tables

class Form1(Form1Template):

    def __init__(self, **properties):
        # Set Form properties and Data Bindings.
        self.init_components(**properties)
        # start with from F
        self.from_F_click()

    def from_F_click(self, **event_args):
        self.TF_label.text = "from Fahrenheit"
        self.TC_label.text = "Celcius"
        self.TK_label.text = "Kelvin"
        self.convertF.visible = True
        self.convertC.visible = False
        self.convertK.visible = False
        self.TF.select()

    def from_C_click(self, **event_args):
        self.TF_label.text = "Fahrenheit"
        self.TC_label.text = "from Celcius"
        self.TK_label.text = "Kelvin"
        self.convertF.visible = False
        self.convertC.visible = True
        self.convertK.visible = False
        self.TC.select()

    def from_K_click(self, **event_args):
        self.TF_label.text = "Fahrenheit"
        self.TC_label.text = "Celcius"
        self.TK_label.text = "from Kelvin"
        self.convertF.visible = False
        self.convertC.visible = False
        self.convertK.visible = True
        self.TK.select()

    def convertF_click(self, **event_args):
        self.f_calculate()

    def convertC_click(self, **event_args):
        self.c_calculate()

    def convertK_click(self, **event_args):
        self.k_calculate()

    def f_calculate(self):
        try:
            fahrenheit = self.TF.text
            fahrenheit = float(fahrenheit)
            celcius = (fahrenheit - 32) / 1.8
            self.TC.text = f'{celcius:.1f}'
            kelvin = celcius + 273.15
            self.TK.text = f'{kelvin:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None

    def c_calculate(self):
        try:
            celcius = self.TC.text
            celcius = float(celcius)
            fahrenheit = (celcius * 1.8) + 32
            self.TF.text =  f'{fahrenheit:.1f}'
            kelvin = celcius + 273.15
            self.TK.text = f'{kelvin:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None

    def k_calculate(self):
        try:
            kelvin = self.TK.text
            kelvin = float(kelvin)
            celcius = kelvin - 273.15
            self.TC.text = f'{celcius:.1f}'
            fahrenheit = (celcius * 1.8) + 32
            self.TF.text =  f'{fahrenheit:.1f}'
        except TypeError as error:
            self.TC.text = None
            self.TK.text = None