Merge pull request #4 from CyB3RC0nN0R/paging

Added paging

menu.c

@@ -1,5 +1,6 @@
 #include "pch.h"
 #include "framework.h"
+
 #include "menu.h"
 
 const struct MenuBorder DEFAULT = {
@@ -18,6 +19,66 @@ const struct MenuBorder SOLID = {
 	186, 205, 201, 187, 200, 188, '[', ']'
 };
 
+void show_menu(const int itemc, const struct MenuItem itemv[], const char title[], const struct MenuBorder* border);
+
+void page(const struct MenuPage* pages, const size_t page_count, const bool infinite_loop)
+{
+	unsigned int page_index = 0;
+	bool action_performed, loop, page_changed = true;
+	char page_key, itemKey;
+	int i;
+
+	do {
+		do {
+			show_menu(pages[page_index].item_count, pages[page_index].items, pages[page_index].title, pages[page_index].border);
+
+			// Wait for user selection
+			putchar('>');
+			putchar(' ');
+
+			loop = pages[page_index].loopback;
+			page_key = _getch();
+
+			// Forward paging
+			if (page_key == 'm' && page_index < page_count - 1)
+				++page_index;
+			// Backward paging
+			else if (page_key == 'n' && page_index > 0)
+				--page_index;
+			else
+			{
+				page_changed = false;
+				itemKey = page_key;
+				do {
+					action_performed = false;
+
+					itemKey != page_key ? itemKey = _getch() : page_key;
+					page_key = 0;
+					for (i = 0; i < pages[page_index].item_count; ++i)
+					{
+						if (pages[page_index].items[i].key == itemKey)
+						{
+							// Perform action
+							system("cls");
+							pages[page_index].items[i].action();
+							action_performed = true;
+
+							// Pause if requested
+							if (pages[page_index].pause)
+							{
+								putchar('\n');
+								system("pause");
+							}
+						}
+					}
+				} while (!action_performed);
+			}
+		} while (loop || page_changed);
+
+		page_index = 0;
+	} while (infinite_loop);
+}
+
 // Checks if a line index should display a menu item
 bool is_item_line(const int line, const int itemc, int* item_index)
 {
@@ -40,11 +101,10 @@ void get_console_dimensions(int* width, int* height)
 	*height = csbi.srWindow.Bottom - csbi.srWindow.Top + 1;
 }
 
-void show_menu(const int itemc, const struct MenuItem itemv[], const char title[], const bool loopback, const bool pause, const struct MenuBorder *border)
+// Draws a menu to the console
+void show_menu(const int itemc, const struct MenuItem itemv[], const char title[], const struct MenuBorder* border)
 {
 	unsigned width, height, item_index;
-	char key;
-	bool action_performed;
 
 	// Clear the console window
 	system("cls");
@@ -63,7 +123,7 @@ void show_menu(const int itemc, const struct MenuItem itemv[], const char title[
 
 			for (unsigned j = 1; j < width - strlen(title) - 2; ++j)
 			{
-				if (j == ((width - strlen(title)) - 2)/ 2)
+				if (j == ((width - strlen(title)) - 2) / 2)
 				{
 					putchar(border->title_left);
 					fputs(title, stdout);
@@ -84,7 +144,7 @@ void show_menu(const int itemc, const struct MenuItem itemv[], const char title[
 			// Print item text
 			putchar(border->line_vertical);
 
- 			if (strcmp(itemv[item_index].text, "BLANK") == 0) {
+			if (strcmp(itemv[item_index].text, "BLANK") == 0) {
 				putchar('\t');
 
 				// BLANK equals 5 characters 
@@ -132,35 +192,4 @@ void show_menu(const int itemc, const struct MenuItem itemv[], const char title[
 			i != height - 2 ? putchar(border->line_vertical) : putchar(' ');
 		}
 	}
-
-	// Wait for user selection
-	putchar('>');
-	putchar(' ');
-	action_performed = false;
-	do {
-		key = _getch();
-		for (int i = 0; i < itemc; ++i)
-		{
-			if (itemv[i].key == key)
-			{
-				// Perform action
-				system("cls");
-				itemv[i].action();
-				action_performed = true;
-
-				// Pause if requested
-				if (pause)
-				{
-					putchar('\n');
-					system("pause");
-				}
-			}
-		}
-	} while (!action_performed);
-
-	// Show menu again if requested
-	if (loopback)
-	{
-		show_menu(itemc, itemv, title, loopback, pause, border);
-	}
 }

menu.h

@@ -21,13 +21,20 @@ struct MenuBorder {
 	char title_right;
 };
 
+// Default borders initialized in menu.c
 const extern struct MenuBorder DEFAULT, MODERN, NO_BORDER, SOLID;
 
-/// <summary>Displaces a CUI menu to the user and lets them choose an option, then calls the corresponding function.</summary>
+/// <summary>Represents a page containing menu items inside a menu.</summary>
-/// <param name="itemc">The length of the array <c>itemv</c> of menu items.</param>
+struct MenuPage {
-/// <param name="itemv">An array of all menu items to display in the menu.</param>
+	const struct MenuItem* items;
-/// <param name="title">The title of the menu.</param>
+	const size_t item_count;
-/// <param name="loopback">If this parameter is set to <c>true</c>, the menu will be displayed again after an action is executed.</param>
+	char* title;
-/// <param name="pause">If this parameter is set to <c>true</c>, a <c>pause</c>command will be run after an action is executed.</param>
+	bool loopback, pause;
-/// <param name="border">Specifies the border in which the menu is displayed.</param>
+	const struct MenuBorder* border;
-void show_menu(const int itemc, const struct MenuItem itemv[], const char title[], const bool loopback, const bool pause, const struct MenuBorder *border);
+};
+
+/// <summary>Constructs a CUI menu with a specific amount of pages.</summary>
+/// <param name="pages">An array of all pages to display.</param>
+/// <param name="page_count">The length of the array <c>pages</c>.</param>
+/// <param name="infinite_loop">Always display the first page after a loopback=false item finished executing.</param>
+void page(const struct MenuPage* pages, const size_t page_count, const bool infinite_loop);