// Navigates to the indicated item and returns the new item
private int NavigateItemVisually (ItemNavigation navigation)
{
int page_size, columns, selected_index = -1;
if (multicolumn) {
columns = items_area.Width / ColumnWidthInternal;
page_size = columns * RowCount;
if (page_size == 0) {
page_size = RowCount;
}
} else {
page_size = items_area.Height / ItemHeight;
}
switch (navigation) {
case ItemNavigation.PreviousColumn: {
if (SelectedIndex - RowCount < 0) {
return -1;
}
if (SelectedIndex - RowCount < top_index) {
top_index = SelectedIndex - RowCount;
UpdateTopItem ();
}
selected_index = SelectedIndex - RowCount;
break;
}
case ItemNavigation.NextColumn: {
if (SelectedIndex + RowCount >= Items.Count) {
break;
}
if (SelectedIndex + RowCount > last_visible_index) {
top_index = SelectedIndex;
UpdateTopItem ();
}
selected_index = SelectedIndex + RowCount;
break;
}
case ItemNavigation.First: {
top_index = 0;
selected_index = 0;
UpdateTopItem ();
break;
}
case ItemNavigation.Last: {
int rows = items_area.Height / ItemHeight;
if (multicolumn) {
selected_index = Items.Count - 1;
break;
}
if (Items.Count < rows) {
top_index = 0;
selected_index = Items.Count - 1;
UpdateTopItem ();
} else {
top_index = Items.Count - rows;
selected_index = Items.Count - 1;
UpdateTopItem ();
}
break;
}
case ItemNavigation.Next: {
if (FocusedItem == Items.Count - 1)
return -1;
if (multicolumn) {
selected_index = FocusedItem + 1;
break;
}
int bottom = 0;
ArrayList heights = new ArrayList ();
if (draw_mode == DrawMode.OwnerDrawVariable) {
for (int i = top_index; i <= FocusedItem + 1; i++) {
int h = GetItemHeight (i);
bottom += h;
heights.Add (h);
}
} else {
bottom = ((FocusedItem + 1) - top_index + 1) * ItemHeight;
}
if (bottom >= items_area.Height) {
int overhang = bottom - items_area.Height;
int offset = 0;
if (draw_mode == DrawMode.OwnerDrawVariable)
while (overhang > 0)
overhang -= (int) heights [offset];
else
offset = (int) Math.Ceiling ((float)overhang / (float) ItemHeight);
top_index += offset;
UpdateTopItem ();
}
selected_index = FocusedItem + 1;
break;
}
case ItemNavigation.Previous: {
if (FocusedItem > 0) {
if (FocusedItem - 1 < top_index) {
top_index--;
UpdateTopItem ();
}
selected_index = FocusedItem - 1;
}
break;
}
case ItemNavigation.NextPage: {
if (Items.Count < page_size) {
NavigateItemVisually (ItemNavigation.Last);
break;
}
if (FocusedItem + page_size - 1 >= Items.Count) {
top_index = Items.Count - page_size;
UpdateTopItem ();
selected_index = Items.Count - 1;
}
else {
if (FocusedItem + page_size - 1 > last_visible_index) {
top_index = FocusedItem;
UpdateTopItem ();
}
selected_index = FocusedItem + page_size - 1;
}
break;
}
case ItemNavigation.PreviousPage: {
int rows = items_area.Height / ItemHeight;
if (FocusedItem - (rows - 1) <= 0) {
top_index = 0;
UpdateTopItem ();
selected_index = 0;
}
else {
if (SelectedIndex - (rows - 1) < top_index) {
top_index = FocusedItem - (rows - 1);
UpdateTopItem ();
}
selected_index = FocusedItem - (rows - 1);
}
break;
}
default:
break;
}
return selected_index;
}
static MenuItem GetNextItem(Menu menu, ItemNavigation navigation)
{
int pos = 0;
bool selectable_items = false;
MenuItem item;
// Check if there is at least a selectable item
for (int i = 0; i < menu.MenuItems.Count; i++)
{
item = menu.MenuItems [i];
if (item.Separator == false && item.Visible == true)
{
selectable_items = true;
break;
}
}
if (selectable_items == false)
{
return(null);
}
switch (navigation)
{
case ItemNavigation.First:
/* First item that is not separator and it is visible*/
for (pos = 0; pos < menu.MenuItems.Count; pos++)
{
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
{
break;
}
}
break;
case ItemNavigation.Last: // Not used
break;
case ItemNavigation.Next:
pos = menu.SelectedItem == null ? -1 : menu.SelectedItem.Index;
/* Next item that is not separator and it is visible*/
for (pos++; pos < menu.MenuItems.Count; pos++)
{
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
{
break;
}
}
if (pos >= menu.MenuItems.Count) /* Jump at the start of the menu */
{
pos = 0;
/* Next item that is not separator and it is visible*/
for (; pos < menu.MenuItems.Count; pos++)
{
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
{
break;
}
}
}
break;
case ItemNavigation.Previous:
if (menu.SelectedItem != null)
{
pos = menu.SelectedItem.Index;
}
/* Previous item that is not separator and it is visible*/
for (pos--; pos >= 0; pos--)
{
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
{
break;
}
}
if (pos < 0) /* Jump at the end of the menu*/
{
pos = menu.MenuItems.Count - 1;
/* Previous item that is not separator and it is visible*/
for (; pos >= 0; pos--)
{
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
{
break;
}
}
}
break;
default:
break;
}
return(menu.MenuItems [pos]);
}
static MenuItem GetNextItem (Menu menu, ItemNavigation navigation)
{
int pos = 0;
bool selectable_items = false;
MenuItem item;
// Check if there is at least a selectable item
for (int i = 0; i < menu.MenuItems.Count; i++) {
item = menu.MenuItems [i];
if (item.Separator == false && item.Visible == true) {
selectable_items = true;
break;
}
}
if (selectable_items == false)
return null;
switch (navigation) {
case ItemNavigation.First:
/* First item that is not separator and it is visible*/
for (pos = 0; pos < menu.MenuItems.Count; pos++) {
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
break;
}
break;
case ItemNavigation.Last: // Not used
break;
case ItemNavigation.Next:
pos = menu.SelectedItem == null ? - 1 : menu.SelectedItem.Index;
/* Next item that is not separator and it is visible*/
for (pos++; pos < menu.MenuItems.Count; pos++) {
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
break;
}
if (pos >= menu.MenuItems.Count) { /* Jump at the start of the menu */
pos = 0;
/* Next item that is not separator and it is visible*/
for (; pos < menu.MenuItems.Count; pos++) {
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
break;
}
}
break;
case ItemNavigation.Previous:
if (menu.SelectedItem != null)
pos = menu.SelectedItem.Index;
/* Previous item that is not separator and it is visible*/
for (pos--; pos >= 0; pos--) {
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
break;
}
if (pos < 0 ) { /* Jump at the end of the menu*/
pos = menu.MenuItems.Count - 1;
/* Previous item that is not separator and it is visible*/
for (; pos >= 0; pos--) {
item = menu.MenuItems [pos];
if (item.Separator == false && item.Visible == true)
break;
}
}
break;
default:
break;
}
return menu.MenuItems [pos];
}
