12. Interfacing with the mouse

#include <ncurses.h>

#define WIDTH 30
#define HEIGHT 10 

int startx = 0;
int starty = 0;

char *choices[] = { 	"Choice 1",
			"Choice 2",
			"Choice 3",
			"Choice 4",
			"Exit",
		  };

int n_choices = sizeof(choices) / sizeof(char *);

void print_menu(WINDOW *menu_win, int highlight);
void report_choice(int mouse_x, int mouse_y, int *p_choice);

int main()
{	int c, choice = 0;
	WINDOW *menu_win;
	MEVENT event;

	/* Initialize curses */
	initscr();
	clear();
	noecho();
	cbreak();	//Line buffering disabled. pass on everything

	/* Try to put the window in the middle of screen */
	startx = (80 - WIDTH) / 2;
	starty = (24 - HEIGHT) / 2;
	
	attron(A_REVERSE);
	mvprintw(23, 1, "Click on Exit to quit (Works best in a virtual console)");
	refresh();
	attroff(A_REVERSE);

	/* Print the menu for the first time */
	menu_win = newwin(HEIGHT, WIDTH, starty, startx);
	print_menu(menu_win, 1);
	/* Get all the mouse events */
	mousemask(ALL_MOUSE_EVENTS, NULL);
	
	while(1)
	{	c = wgetch(menu_win);
		switch(c)
		{	case KEY_MOUSE:
			if(getmouse(&event) == OK)
			{	/* When the user clicks left mouse button */
				if(event.bstate & BUTTON1_PRESSED)
				{	report_choice(event.x + 1, event.y + 1, &choice);
					if(choice == -1) //Exit chosen
						goto end;
					mvprintw(22, 1, "Choice made is : %d String Chosen is \"%10s\"", choice, choices[choice - 1]);
					refresh(); 
				}
			}
			print_menu(menu_win, choice);
			break;
		}
	}		
end:
	endwin();
	return 0;
}


void print_menu(WINDOW *menu_win, int highlight)
{
	int x, y, i;	

	x = 2;
	y = 2;
	box(menu_win, 0, 0);
	for(i = 0; i < n_choices; ++i)
	{	if(highlight == i + 1)
		{	wattron(menu_win, A_REVERSE); 
			mvwprintw(menu_win, y, x, "%s", choices[i]);
			wattroff(menu_win, A_REVERSE);
		}
		else
			mvwprintw(menu_win, y, x, "%s", choices[i]);
		++y;
	}
	wrefresh(menu_win);
}

/* Report the choice according to mouse position */
void report_choice(int mouse_x, int mouse_y, int *p_choice)
{	int i,j, choice;

	i = startx + 2;
	j = starty + 3;
	
	for(choice = 0; choice < n_choices; ++choice)
		if(mouse_y == j + choice && mouse_x >= i && mouse_x <= i + strlen(choices[choice]))
		{	if(choice == n_choices - 1)
				*p_choice = -1;		
			else
				*p_choice = choice + 1;	
			break;
		}
}