widgets.c

一个很好的SDL建立应用程序界面的例子

void addVSlider(void *w, VSLIDER *vs)
{
	BLIST		*list;
	WINDOW	*win = (WINDOW *) w;

	vs->parent = win;
	vs->x += win->x;
	vs->y += win->y;

	if (win->list == NULL)
	{
		list = (BLIST *) malloc(sizeof(BLIST));
		win->list = list;
	}
	else
	{
		list = win->list;

		while (list->next)
			list = list->next;

		list->next = (BLIST *) malloc(sizeof(BLIST));
		list = list->next;
	}

	list->thislist.button = (BUTTON *) vs;
	list->next = NULL;
}

// Add a horizontal slider to a window

void addHSlider(void *w, HSLIDER *hs)
{
	BLIST		*list;
	WINDOW	*win = (WINDOW *) w;

	hs->parent = win;
	hs->x += win->x;
	hs->y += win->y;

	if (win->list == NULL)
	{
		list = (BLIST *) malloc(sizeof(BLIST));
		win->list = list;
	}
	else
	{
		list = win->list;

		while (list->next)
			list = list->next;

		list->next = (BLIST *) malloc(sizeof(BLIST));
		list = list->next;
	}

	list->thislist.button = (BUTTON *) hs;
	list->next = NULL;
}

// Add a TextBox to a window

void addTextBox(void *w, TEXTBOX *tbox)
{
	BLIST		*list;
	WINDOW	*win = (WINDOW *) w;

	tbox->parent = win;

	if (win->list == NULL)
	{
		list = (BLIST *) malloc(sizeof(BLIST));
		win->list = list;
	}
	else
	{
		list = win->list;

		while (list->next)
			list = list->next;

		list->next = (BLIST *) malloc(sizeof(BLIST));
		list = list->next;
	}

	list->thislist.button = (BUTTON *) tbox;
	list->next = NULL;

	if (tbox->w > win->w)
			win->w = tbox->w;

	tbox->x += win->x;
	tbox->y += win->y;
}

// Add a string to a TextBox

void addText(TEXTBOX *tbox, char *str)
{
	TLIST	*next, *prev;

	next = prev = tbox->text;

	if (!next)						// first one in list
	{
		next = (TLIST *) malloc(sizeof(TLIST));
		next->str = str;
		next->fg = tbox->fg;
		next->bg = tbox->bg;
		next->prev = NULL;
		next->next = NULL;
		tbox->text = next;
		tbox->line = 0;
	}
	else
	{
		while (next->next)		// find last in list
		{
			prev = next;
			next = next->next;
		}

		prev = next;
		next->next = (TLIST *) malloc(sizeof(TLIST));
		next = next->next;
		prev->next = next;
		next->str = str;
		next->fg = tbox->fg;
		next->bg = tbox->bg;
		next->prev = prev;
		next->next = NULL;
	}

	tbox->lines++;
}

// Add a string to a TextBox at a specific location

void addTextEntry(TEXTBOX *tbox, char *str, int line)
{
	int	i = 1;
	TLIST	*next, *prev, *entry;

	next = tbox->text;
	prev = NULL;
	entry = (TLIST *) malloc(sizeof(TLIST));
	entry->str = str;

	while (next && i < line)
	{
		prev = next;
		next = next->next;
		i++;
	}

	if (!prev)			// add first line in list
	{
		entry->prev = NULL;

		if (!next)		// empty list
			entry->next = NULL;
		else				// add as first line in list
			entry->next = next;

		tbox->text = entry;
	}
	else					// not first in list
	{
		prev->next = entry;
		entry->prev = prev;

		if (next)
		{
			entry->next = next;
			next->prev = entry;
		}
		else
			entry->next = NULL;
	}
}

// Set the current line of a TextBox to a specific line

void setTListEntry(TEXTBOX *tbox, int line)
{
	int	i;
	TLIST	*entry;

	entry = tbox->text;

	if (!entry)
		return;

	i = 0;

	while (entry && i < line)
	{
		entry = entry->next;
		i++;
	}

	if (entry)
	{
		tbox->line = line;
		showTextBox(tbox);
	}
}

// Increment the TextBox line by some amount

void incTListEntry(TEXTBOX *tbox, int count)
{
	int	line;

	line = tbox->line + count;

	if (line < 0)
		line = 0;
	else if (line >= tbox->lines)
		line = tbox->lines - 1;

	tbox->line = line;
	showTextBox(tbox);
}

// Decrement the TextBox line by some amount

void decTListEntry(TEXTBOX *tbox, int count)
{
	int	line;

	line = tbox->line - count;

	if (line < 0)
		line = 0;
	else if (line >= tbox->lines)
		line = tbox->lines - 1;

	tbox->line = line;
	showTextBox(tbox);
}

// Remove all text from a TextBox

void removeTList(TEXTBOX *tbox)
{
	TLIST	*entry, *prev;

	entry = tbox->text;

	if (!entry)
		return;

	tbox->text = NULL;

	while (entry)
	{
		prev = entry;
		entry = entry->next;
		free(prev);
	}

	tbox->lines = 0;
}

// Remove a specific string from a TextBox

void removeTListEntry(TEXTBOX *tbox, int line)
{
	int	i = 1;
	TLIST	*entry, *prev;

	entry = tbox->text;

	if (!entry)
		return;

	prev = NULL;

	while (entry && i < line)
	{
		prev = entry;
		entry = entry->next;
		i++;
	}

	if (prev && entry)
		prev->next = entry->next;

	if (entry)
	{
		if (entry->next)
			entry->next->prev = prev;

		free(entry);
		tbox->lines--;
	}
}

// Swap foreground and background colors of a
// string in a text box (highlighting)

void toggleTextHighlight(TEXTBOX *tbox, int line)
{
	int	i = 1;
	TLIST	*entry;

	entry = tbox->text;

	if (!entry)
		return;

	while (entry && i < line)
	{
		entry = entry->next;
		i++;
	}

	if (entry)
	{
		i = entry->fg;
		entry->fg = entry->bg;
		entry->bg = i;
	}
}

// Retrieve the string from a specific line in a TextBox

char *getText(TEXTBOX *tbox, int line)
{
	int	i = 1;
	TLIST	*entry;

	entry = tbox->text;

	if (!entry)
		return NULL;

	while (entry && i < line)
	{
		entry = entry->next;
		i++;
	}

	if (entry)
		return entry->str;

	return NULL;
}

void addInputBox(void *w, INPUTBOX *ibox)
{
	BLIST		*list;
	WINDOW	*win = (WINDOW *) w;

	ibox->parent = win;

	if (win->list == NULL)
	{
		list = (BLIST *) malloc(sizeof(BLIST));
		win->list = list;
	}
	else
	{
		list = win->list;

		while (list->next)
			list = list->next;

		list->next = (BLIST *) malloc(sizeof(BLIST));
		list = list->next;
	}

	list->thislist.button = (BUTTON *) ibox;
	list->next = NULL;
}

// Add a string to an InputBox

void addInput(INPUTBOX *ibox, char *str)
{
	SLIST	*next, *prev;

	next = prev = ibox->text;

	if (!next)						// first one in list
	{
		next = (SLIST *) malloc(sizeof(SLIST));
		next->str = str;
		next->prev = NULL;
		next->next = NULL;
		ibox->text = next;
		ibox->line = 0;
	}
	else
	{
		while (next->next)		// find last in list
		{
			prev = next;
			next = next->next;
		}

		prev = next;
		next->next = (SLIST *) malloc(sizeof(SLIST));
		next = next->next;
		prev->next = next;
		next->str = str;
		next->prev = prev;
		next->next = NULL;
	}

	ibox->lines++;
}

// Draw a solid bar of given width and height

void makeBar(int x, int y, int w, int h, int color)
{
	int	i, j;

	for (i=0; i<w; i++)
	{
		for (j=0; j<h; j++)
			setPixel(x + i, y + j, color);
	}
}

// Display a widget on the screen

void showWidget(void *w)
{
	WIDGET	*x = (WIDGET *) w;

	addWList(w);

	switch (x->p.type)
	{
		case WindowType:
		case MenuType:
			showWindow((WINDOW *) x);
			break;

		case VMenuType:
			showVMenu((VMENU *) x);
			break;

		case TextBoxType:
			showTextBox((TEXTBOX *) x);
			break;

		case InputBoxType:
			showInputBox((INPUTBOX *) x);
			break;

		case ButtonType:
			showButton((BUTTON *) x);
			break;

		case CheckBoxType:
			showCheckBox((CHECKBOX *) x);
			break;

		case AlertType:
			showAlertBox((WINDOW *) x);
			break;

		case NoticeType:
			showNoticeBox((WINDOW *) x);
			break;

		case LabelType:
			showLabel((LABEL *) x);
			break;

		case HLabelType:
			showHLabel((HLABEL *) x);
			break;

		case VSliderType:
			showVSlider((VSLIDER *) x);
			break;

		case HSliderType:
			showHSlider((HSLIDER *) x);
			break;
	}
}

// Display a Window

void showWindow(WINDOW *w)			// render a window or horizontal menu & associated buttons
{
	int		x, y;
	BUTTON	*btn;
	BLIST		*bl;

	makeBar(w->x + 1, w->y + 1, w->w - 2, w->h - 2, w->bg);	// body of window
	makeBar(w->x, w->y, w->w, 1, w->hi);							// top border
	makeBar(w->x + 1, w->y + w->h - 1, w->w - 1, 1, w->lo);	// bottom border
	makeBar(w->x, w->y, 1, w->h, w->hi);							// left border
	makeBar(w->x + w->w - 1, w->y + 1, 1, w->h - 1, w->lo);	// right border

	x = w->x + 4;
	y = w->y + 1;
	bl = w->list;

	while (bl)
	{
		btn = bl->thislist.button;

		if (btn)
			showWidget(btn);

		bl = bl->next;
	}
}

// Display a vertical menu

void showVMenu(VMENU *w)			// render a vertical menu & associated buttons
{
	int		x, y;
	BUTTON	*btn;
	BLIST		*bl;

	makeBar(w->x + 1, w->y + 1, w->w - 2, w->h - 2, w->bg);	// body of window
	makeBar(w->x, w->y, w->w, 1, w->hi);							// top border
	makeBar(w->x + 1, w->y + w->h, w->w - 1, 1, w->lo);		// bottom border
	makeBar(w->x, w->y, 1, w->h, w->hi);							// left border
	makeBar(w->x + w->w - 1, w->y + 1, 1, w->h - 1, w->lo);	// right border

	x = w->x + 4;
	y = w->y + 1;
	bl = w->list;

	while (bl)
	{
		btn = bl->thislist.button;

		if (btn)
			showWidget(btn);

		bl = bl->next;
	}
}

//
// Display an AlertBox
//
// An alert box has only three "buttons":
//  1) The (possibly multi-line) text,
//  2) Cancel button,
//  3) OK button.
//
// The Cancel and OK buttons should be on the last line of the
// "window", and should be appropriately left/right centered.
//

void showAlertBox(WINDOW *win)			// render an alertbox & associated buttons
{
	int		i, j, x, y, w, center;
	char		*text;
	BUTTON	*btn = NULL;
	BUTTON	*canbtn = NULL;
	BUTTON	*okbtn = NULL;
	BLIST		*bl;
	char		line[128];

	x = win->x + 4;
	y = win->y;
	w = win->w;

	bl = win->list;
	makeBar(x, y + 1, w, win->h, win->bg);				// body of box
	makeBar(x, y, win->w, 1, win->hi);					// top of alert box
	makeBar(x, y + win->h, win->w, 1, win->lo);		// bottom of box
	makeBar(x, y, 1, win->h, win->hi);					// left side
	makeBar(x + win->w - 1, y, 1, win->h, win->lo);	// right side

	y++;
	btn = bl->thislist.button;				// do the text "button"
	btn->w = w;
	text = btn->text;

	x += 4;
	i = j = 0;

	while (text[i])
	{
		if (text[i] == '\n')
		{
			line[j] = '\0';
			printString(x, y, btn->fg, btn->bg, line);
			y += FONT_HEIGHT;
			j = 0;
			i++;
		}
		else
			line[j++] = text[i++];
	}

	if (j)					// output last line of text
	{
		line[j] = '\0';
		printString(x, y, btn->fg, btn->bg, line);
		y += FONT_HEIGHT;
	}
	else if (text[i - 1] == '\n')
		y += FONT_HEIGHT;

	bl = bl->next;
	canbtn = bl->thislist.button;
	bl = bl->next;
	okbtn = bl->thislist.button;

	center = win->w / 2;					// center cancel and ok buttons, if possible
	i = canbtn->w + okbtn->w + 18;
	w = i / 2;
	w = center - w;

	if (w + i < win->w)
		x += w;

				// now do the Cancel button
	x += 2;
	y += 4;
	canbtn->x = x;
	canbtn->y = y;
	addWList(canbtn);
	x += canbtn->w;

				// now do the OK button
	x += 8;
	okbtn->x = x;
	okbtn->y = y;
	addWList(okbtn);
}

//
// Display a NoticeBox
//
// A notice box has only two "buttons":
//  1) The (possibly multi-line) text,
//  2) Close button,
//
// The Close button should be on the last line of the
// "window", and should be appropriately left/right centered.
//

void showNoticeBox(WINDOW *win)			// render a noticebox & associated buttons
{
	int		i, j, x, y, w, center;
	char		*text;
	BUTTON	*btn = NULL;
	BUTTON	*closebtn = NULL;
	BLIST		*bl;
	char		line[128];

	x = win->x + 4;
	y = win->y;
	w = win->w;

	bl = win->list;
	makeBar(x, y + 1, w, win->h, win->bg);				// body of box
	makeBar(x, y, win->w, 1, win->hi);					// top of notice box
	makeBar(x, y + win->h, win->w, 1, win->lo);		// bottom of box
	makeBar(x, y, 1, win->h, win->hi);					// left side
	makeBar(x + win->w - 1, y, 1, win->h, win->lo);	// right side

	y++;
	btn = bl->thislist.button;				// do the text "button"
	btn->w = w;
	text = btn->text;

	x += 4;
	i = j = 0;

	while (text[i])
	{
		if (text[i] == '\n')
		{
			line[j] = '\0';
			printString(x, y, btn->fg, btn->bg, line);
			y += FONT_HEIGHT;
			j = 0;
			i++;
		}
		else
			line[j++] = text[i++];
	}

	if (j)					// output last line of text
	{
		line[j] = '\0';
		printString(x, y, btn->fg, btn->bg, line);
		y += FONT_HEIGHT;
	}
	else if (text[i - 1] == '\n')
		y += FONT_HEIGHT;

	bl = bl->next;
	closebtn = bl->thislist.button;

	center = win->w / 2;					// center close button, if possible
	i = closebtn->w + 18;
	w = i / 2;
	w = center - w;

	if (w + i < win->w)
		x += w;

				// now do the Close button
	x += 2;