CalcForm.h Source File

00001 /** $Revision: 1.4 $
00002     Last updated: $Date: 2002/09/20 12:21:30 $
00003     
00004     Copyright (C) 2001-2002 Vlad Mereuta <dizzy@users.sourceforge.net>
00005 
00006     This program is free software; you can redistribute it and/or modify
00007     it under the terms of the GNU General Public License as published by
00008     the Free Software Foundation; either version 2 of the License, or
00009     any later version.
00010 
00011     This program is distributed in the hope that it will be useful,
00012     but WITHOUT ANY WARRANTY; without even the implied warranty of
00013     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00014     GNU General Public License for more details.
00015 
00016     You should have received a copy of the GNU General Public License
00017     along with this program; if not, write to the Free Software
00018     Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */
00019 
00020 #ifndef __CALC_FORM__
00021 #define __CALC_FORM__
00022 
00023 #include <PalmOS.h>
00024 #include <FloatMgr.h>
00025 
00026 #include "Form.h"
00027 
00028 ///class implements a calculator
00029 class CalculatorForm : public Form
00030 {
00031 public:
00032     ///initial amount to be diplayed
00033     Int32 amount;
00034     ///sign of the amount memorised
00035     Int8 sign;
00036 
00037     ///constructor, does nothing
00038     CalculatorForm() FORM_SECTION1;
00039     /** returns reference to SplitsForm instance. Only allowed way to use the class */
00040     static CalculatorForm* instance() FORM_SECTION1;
00041 
00042 private:
00043     ///current calculator entry
00044     Char entry[32];
00045     ///text for decimal separator
00046     Char dotLabel[2];
00047     FlpCompDouble accu;
00048     FlpCompDouble operand;
00049     Char operation;
00050     Boolean disp_accu;
00051     ///singleton reference to this form 
00052     static CalculatorForm* _instance;
00053     
00054     ///updates calculator display display
00055     void updateDisplay() FORM_SECTION1;
00056     ///redraws form and update display
00057     Boolean handleUpdateEvent(UInt16 update_code) FORM_SECTION1;
00058     ///draws initial calculator
00059     Boolean handleOpenEvent() FORM_SECTION1;
00060     ///handles all control interaction
00061     Boolean handleCtlSelectEvent (UInt16 control_id) FORM_SECTION1;
00062     ///update entry with information from a button
00063     void handleButton(Char c) FORM_SECTION1;
00064     ///carry out operation
00065     void doMath(Char newop) FORM_SECTION1;
00066     ///flip sign
00067     void flipSign(void) FORM_SECTION1;
00068 };
00069 #endif