www.pudn.com > PocketC.zip > calc.c

// Simple calc 
 
// This sample demonstrate advanced PocketC concepts: 
// simulating structures, indirect function calls. 
// 
// This sample sets up an event-based applet framework, and 
// creates a integer calculator using it. 
// 
// Since malloc() returns an array of ints, and we need a 
// more complex structure for our buttons, we create a 
// template for the button structure out of globals. Since 
// globals reside in memory in the same order that they are 
// declared, we can use a block of globals to initialize our 
// button list items. This works because memcpy() copies 
// not only memory contents, but also memory types. 
 
include "calc_framework.c" 
 
updateDisp(int num) { 
  rect(0, 0, 15, 160, 39, 0); 
  textattr(6, 1, 0); 
  textalign(12); 
  text(159, 16, num); 
  textattr(0, 1, 0); 
} 
 
int total; 
int operand; 
char operator; 
 
doOp() { 
  if (operator=='+') { 
    total = total + operand; 
  } else if (operator=='-') { 
    total = total - operand; 
  } else if (operator=='*') { 
    total = total * operand; 
  } else if (operator=='/') { 
    total = total / operand; 
  } 
  operand = 0; 
  operator = '+'; 
  updateDisp(total); 
} 
 
 
// common code for each button 
#define NUM_BEG { operand = operand * 10 + 
#define NUM_END ; updateDisp(operand); } 
 
// button handlers 
but0() NUM_BEG 0 NUM_END 
but1() NUM_BEG 1 NUM_END 
but2() NUM_BEG 2 NUM_END 
but3() NUM_BEG 3 NUM_END 
but4() NUM_BEG 4 NUM_END 
but5() NUM_BEG 5 NUM_END 
but6() NUM_BEG 6 NUM_END 
but7() NUM_BEG 7 NUM_END 
but8() NUM_BEG 8 NUM_END 
but9() NUM_BEG 9 NUM_END 
butC() { operator = '+'; operand = 0; total = 0; updateDisp(0); } 
butPlus() { doOp(); operator = '+'; } 
butMinus() { doOp(); operator = '-'; } 
butMult() { doOp(); operator = '*'; } 
butDiv() { doOp(); operator = '/'; } 
butEq() { doOp(); } 
exitfunc() { exitflag = 1; } 
 
main() { 
  // initialize graphics 
  graph_on(); 
  title("Simple Calc"); 
  // create our buttons 
  addButton("7", but7, 30, 40, 55, 65); 
  addButton("8", but8, 55, 40, 80, 65); 
  addButton("9", but9, 80, 40, 105, 65); 
  addButton("/", butDiv, 105, 40, 130, 65); 
 
  addButton("4", but4, 30, 65, 55, 90); 
  addButton("5", but5, 55, 65, 80, 90); 
  addButton("6", but6, 80, 65, 105, 90); 
  addButton("*", butMult, 105, 65, 130, 90); 
 
  addButton("1", but1, 30, 90, 55, 115); 
  addButton("2", but2, 55, 90, 80, 115); 
  addButton("3", but3, 80, 90, 105, 115); 
  addButton("-", butMinus, 105, 90, 130, 115); 
 
  addButton("0", but0, 30, 115, 55, 140); 
  addButton("C", butC, 55, 115, 80, 140); 
  addButton("=", butEq, 80, 115, 105, 140); 
  addButton("+", butPlus, 105, 115, 130, 140); 
 
  addButton("Exit", exitfunc, 30, 145, 130, 159); 
 
  operator='+'; 
  updateDisp(0); 
  // let's go! 
  eventLoop(); 
}