Design Title 1: Design the calculator program for the GUI interface, the user can enter the value of the calculated value by the mouse, plus, minus, multiplied, and divide the mixed operation.
This topic is through:
Mouse Click to input an integer by clicking various digital buttons; input arithmetic operation by clicking the operation symbol button; by clicking the Calculator panel Click the CE button to clear the input.
Program output
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Panel output or output error information (when the system is wrong). // Wang Rui's MycalculatorImport java.awt. *;
Import java.awt.event. *;
Public Class Mycalculator Extends WINDOWAPTER IMPLEments ActionListener {
PRIVATE FRAME F;
Private Button B1, B2, B3, B4, B5, B6, B7, B8, B9, B10, B11, B12,
B13, B14, B15, B16, B17, B18, B19;
Private textfield F1;
Private Double ANS = 0; // Temporary storage results, the result is finally final
Private double n1 = 0; // Defined to store the number to be entered, the initial value is no input number
Private int ob = 0; // At the beginning of the first value, no operation
Private boolean Hasop = false; // Initial value is not pressed
Private Boolean Dot = false; // Defined as a calculation of the small number of calculations, the initial value is no size
Public static void main (string args []) {
Mycalculator be = new mycalculator ();
BE.GO ();
}
Public void Go () {
f = new frame ("Wang Rui's calculator");
F.setLayout (New GridLayout (4, 4));
F1 = new textfield (", 10);
B1 = New Button ("1");
B2 = New Button ("2");
B3 = New Button ("3");
B4 = New Button ("CE");
B5 = New Button ("4");
B6 = New Button ("5");
B7 = New Button ("6");
B8 = New Button (" ");
B9 = New Button ("7");
B10 = New Button ("8");
B11 = New Button ("9");
B12 = New Button ("-");
B13 = new button ("*");
B14 = New Button ("0");
B15 = New Button (".");
B16 = New Button ("/");
B17 = New Button ("=");
B18 = New button (");
B19 = New Button (")");
F.Add (f1);
F.Add (b1);
F.Add (b2);
F.Add (b3);
F.Add (b4);
F.Add (b5);
F.Add (b6);
F.Add (b7); f.Add (b8);
F.Add (b9);
F.Add (b10);
F.Add (b11);
F.Add (b12);
F.Add (b13);
F.Add (b14);
F.Add (b15);
F.Add (b16);
F.Add (b17);
F.Add (b18);
F.Add (b19);
F.PACK ();
F.setVisible (TRUE);
F.Add (F1, "Center");
F.AddWindowListener (this);
F.setsize (300, 150);
F.setVisible (TRUE);
}
// Implement an actionPerformed () method in the ActionListener interface
Public Void ActionPerformed (ActionEvent E) {
String D = E.GetActionCommand ();
CHAR C = D.Charat (0);
Switch (c)
{
Case ' ': // Press the operation symbol for the first time and before it
Case '-': // No number is pressed and not even press twice
Case '*':
Case '/': // first calculate the result
IF (OP! = 0 '&&! Hasop) // Press the equal sign
Result ();
N1 = double.Valueof (Final.getText ()). DoubleValue ();
Op = C;
Hasop = True;
DOT = false;
Break;
Case '=': // Press the equal sign
Result ();
Break;
Case '.': // Press the decimal point
IF (! dot)
{
Final.setText (Final.getText () ".");
Dot = true;
}
Break;
Case 'CE': // Press Clear
N1 = 0;
Op = '0';
Hasop = false;
DOT = false;
Final.Settext ("0");
Break;
DEFAULT: // Press the normal execution of the number
IF (Final.getText (). Equals ("0") || Hasop)
{
Final.Settext (d);
Hasop = false;
}
Else
Final.Settext (Final.getText () D);
}
}
//Calculation results
Private void result ()
{
Double N2 = double.valueof (Final.getText ()). DoubleValue ();
Switch (OP)
{
Case ' ':
ANS = N1 N2;
Break;
Case '-':
ANS = N1 - N2;
Break;
Case '*':
ANS = N1 * 2;
Break;
Case '/':
ANS = N1 / N2;
}
Op = '0';
Hasop = True;
DOT = false;
N1 = ANS;
Final.Settext (String.Valueof (ANS));
}
// Cover the WindowClosing () method in the Windowadapter class
Public void windowClosing (WindowEvent E) {
System.exit (0);
}
