Kivy_Calculator_Application

from kivy.app import App
from kivy.uix.boxlayout import BoxLayout
from kivy.uix.gridlayout import GridLayout
from kivy.uix.button import Button
from kivy.uix.label import Label

class CalculatorApp(App):
    def build(self):
        self.operators = ['+', '-', '*', '/']
        self.last_was_operator = None
        self.result = None
        self.input_text = ""

        layout = BoxLayout(orientation='vertical', padding=20)

        self.result_label = Label(
            text="Enter an expression",
            font_size=30,
            size_hint_y=None,
            height=100,
            halign='right'
        )

        layout.add_widget(self.result_label)

        buttons = [
            ['7', '8', '9', '/'],
            ['4', '5', '6', '*'],
            ['1', '2', '3', '-'],
            ['.', '0', '=', '+']
        ]

        grid_layout = GridLayout(cols=4, spacing=10, size_hint_y=None, height=400)

        for row in buttons:
            for label in row:
                button = Button(
                    text=label,
                    font_size=24,
                    background_color=(0.5, 0.5, 0.5, 1),
                    color=(1, 1, 1, 1),
                )
                button.bind(on_press=self.on_button_press)
                grid_layout.add_widget(button)

        layout.add_widget(grid_layout)

        return layout

    def on_button_press(self, instance):
        current = self.result_label.text
        button_text = instance.text

        if button_text == "=":
            self.on_solution(instance)
        else:
            if self.last_was_operator and button_text in self.operators:
                return
            elif current == "Enter an expression":
                self.result_label.text = button_text
            else:
                new_text = current + button_text
                self.result_label.text = new_text
        self.last_was_operator = button_text in self.operators

    def on_solution(self, instance):
        text = self.result_label.text
        try:
            self.result = str(eval(self.result_label.text))
            self.result_label.text = self.result
        except:
            self.result_label.text = "Error"


if __name__ == '__main__':
    app = CalculatorApp()
    app.run()