Initial commit

Integrating/Calculator.py

@@ -0,0 +1,178 @@
+#!/usr/bin/python3
+
+import sys
+import math
+import gi
+gi.require_version('Gtk', '3.0')
+from gi.repository import Gtk, Pango
+
+
+
+class SignalHandlers():
+
+    def __init__(self, builder):
+        self.builder = builder
+        self.entry = None
+        self.OP_NULL = 0
+        self.OP_ADD = 1
+        self.OP_SUBTRACT = 2
+        self.OP_MULTIPLY = 3
+        self.OP_DIVIDE = 4
+        self.OP_POWER = 5
+        self.clear_value = False
+        self.value_set = False
+        self.prev_value = 0
+        self.pending_op = self.OP_NULL
+
+        entry = builder.get_object("output")
+        self.entry = entry
+        fd = Pango.font_description_from_string("Monospace Bold 16")
+        entry.set_text("0")
+        entry.modify_font(fd)
+
+        # Set user data for the operators and decimal buttons.
+        add = builder.get_object("add")
+        add.operator = self.OP_ADD
+        sub = builder.get_object("sub")
+        sub.operator = self.OP_SUBTRACT
+        mul = builder.get_object("mul")
+        mul.operator = self.OP_MULTIPLY
+        div = builder.get_object("div")
+        div.operator = self.OP_DIVIDE
+        power = builder.get_object("power")
+        power.operator = self.OP_POWER
+        decimal = builder.get_object("decimal")
+        decimal.number = 10
+
+        # Set the user data for the number buttons.
+        for i in range(0, 10):
+            name = "num_%i" % (i,)
+            num = builder.get_object(name)
+            num.number = i
+
+    def do_operation(self, entry, value):
+        # Perform the specified operation, either add, subtract, multiply, 
+        # divide, or the power operation.
+
+        # Perform the operation on prev_value with the new value and store 
+        # the result back into prev_value.
+        if self.pending_op == self.OP_ADD:
+            self.prev_value += value
+        elif self.pending_op == self.OP_SUBTRACT:
+            self.prev_value -= value
+        elif self.pending_op == self.OP_MULTIPLY:
+            self.prev_value *= value
+        elif self.pending_op == self.OP_DIVIDE:
+            self.prev_value /= value;
+        elif self.pending_op == self.OP_POWER:
+            self.prev_value = pow(prev_value, value)
+        else:
+            return
+
+        # Reset the pending operation and create a string with the new value.
+        self.pending_op = self.OP_NULL
+        entry.set_text(self.format_num(self.prev_value))
+
+    def on_num_clicked(self, button):
+        # Retrieve the number that is stored in user data.
+        num = button.number
+
+        # Clear the value if a new number should be entered.
+        if self.clear_value:
+            self.entry.set_text("0")
+            self.clear_value = False
+
+        # Append a decimal place to the GtkEntry. Make sure to keep track of
+        #  whether the decimal place was already entered.
+        text = self.entry.get_text()
+        if (num == 10):
+            if len(text) > 9:
+                return
+            elif text.find('.') >= 0:
+                return
+            else:
+                text = text + '.'
+        # Append a number place to the GtkEntry if the length is less than 10.
+        else:
+            text = text + str(num)
+            if len(text) > 10:
+                    return
+        # Remove preceeding zeros. 
+        text = text.lstrip('0')
+        self.entry.set_text(text)
+
+    def on_equal_clicked(self, button):
+        # Perform any pending operations because the equal button was pressed.
+        value = float(self.entry.get_text())
+  
+        self.do_operation(self.entry, value)
+        self.clear_value = True
+        self.value_set = False
+
+    def on_op_clicked(self, button):
+        op = button.operator
+        value = float(self.entry.get_text())
+
+        # Perform any pending operations and then store the new operation.
+        self.do_operation(self.entry, value)
+        self.pending_op = op;
+        self.clear_value = True
+
+        # Set the current value as the previous value if it should be 
+        # overwritten.
+        if not self.value_set:
+            self.prev_value = value;
+            self.value_set = True
+
+    def on_sign_clicked(self, button):
+        value = float(self.entry.get_text())
+        
+        # You cannot negate a value of zero.
+        if value == 0.0:
+            return
+        value *= -1
+        
+        self.entry.set_text(self.format_num(value))
+
+    def on_sqrt_clicked(self, button):
+        # Take the square root of the current value.
+        value = math.sqrt(float(self.entry.get_text()))
+  
+        self.entry.set_text(self.format_num(value))
+
+    def on_clear_clicked(self, button):
+        self.entry.set_text("0")
+  
+        self.clear_value = False
+        self.value_set = False
+        self.prev_value = 0
+        self.pending_op = self.OP_NULL
+
+    def format_num(self, num):
+        text = str(num)
+        text = text.rstrip('0')
+        text = text.lstrip('0')
+        text = text.rstrip('.')  # remove trailing decimal
+        return text
+
+class Application(Gtk.Application):
+
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, application_id="org.example.myapp",
+                         **kwargs)
+        self.window = None
+        self.builder = None
+
+    def do_activate(self):
+        if not self.window:
+            self.builder = Gtk.Builder()
+            self.builder.add_from_file("./Calculator.glade")
+            self.window = self.builder.get_object("window")
+            self.builder.connect_signals(SignalHandlers(self.builder))
+            self.add_window(self.window)
+        self.window.show_all()
+
+if __name__ == "__main__":
+    app = Application()
+    app.run(sys.argv)
+