pointertest.c

   1 #include <stdlib.h>
   2 #include <stdio.h>
   3
   4 char s0[] = "\0";
   5 char s1[] = "Line1 text\0";
   6 char s2[] = "line2 text\0";
   7 char s3[] = "line3 text\0";
   8 char s4[] = "line4 text\0";
   9
  10
  11 char* screen1[] = {s0};
  12 #define screen1Len (sizeof(screen1)/sizeof(&screen1))
  13 char* screen2[] = {s0,s1,s2,s3,s4};
  14 #define screen2Len (sizeof(screen2)/sizeof(&screen2))
  15 char* screen3[] = {s0,s1};
  16 #define screen3Len (sizeof(screen3)/sizeof(&screen3))
  17
  18 char** screens[] = {screen1,screen2,screen3};
  19 int screensLen[] = {screen1Len,screen2Len,screen3Len};
  20
  21 void drawScreen(char**,unsigned,int);
  22 void next(char**,unsigned*,int);
  23 void prev(char**,unsigned*,int);
  24 float min(float a, float b){return (a < b ? a : b);}
  25
  26 int main(){
  27         char key=0xff;
  28         int i = 0;
  29         unsigned* offset;
  30         offset = malloc(sizeof(unsigned));
  31         *offset = 0;
  32         drawScreen(screens[1],0,screensLen[1]);
  33         while(1){
  34                 key = getchar();
  35                 switch (key) {
  36                         case 'n' : {
  37                                 next(screens[1],offset,screensLen[1]);
  38                         }; break;
  39                         case 'p' : {
  40                                 prev(screens[1],offset,screensLen[1]);
  41                         }; break;
  42                 }
  43         }
  44         return 1;
  45 }
  46
  47 void drawScreen(char** s,unsigned yo,int scrLen){
  48         int i = 0;
  49         system("clear");
  50         for(i; i<(unsigned)min(scrLen, 2); i++){
  51                 printf("%d ",i);
  52                 printf(i==1?">":" ");
  53                 printf("%s\n",s[i+yo]);
  54         }
  55 }
  56
  57 void next(char** s,unsigned* menuOffset,int scrLen){
  58                 *menuOffset = ((*menuOffset)+2==scrLen)?(*menuOffset):(((*menuOffset)+1));
  59                 drawScreen(s,*menuOffset,scrLen);
  60 }
  61
  62 void prev(char** s, unsigned* menuOffset,int scrLen){
  63                 *menuOffset = (*menuOffset==0)?(*menuOffset):((*menuOffset)-1);
  64                         drawScreen(s,*menuOffset,scrLen);
  65 }