private ShengAddressBarDropDown GetButtonDropDown(IShengAddressNode addressNode)
{
ShengAddressBarDropDown dropDown = new ShengAddressBarDropDown();
if (this.DropDownRenderer != null)
{
dropDown.Renderer = this.DropDownRenderer;
}
dropDown.LayoutStyle = ToolStripLayoutStyle.Table;
dropDown.MaximumSize = new Size(1000, 400);
dropDown.Opening += new CancelEventHandler(DropDown_Opening);
/*
* This is the primary bottleneck for this app, creating all the necessary drop-down menu items.
*
* To optimize performance of this control, this is the main area that needs tuning.
*/
IShengAddressNode curNode = null;
for (int i = 0; i < addressNode.Children.Length; i++)
{
curNode = (IShengAddressNode)addressNode.Children.GetValue(i);
ShengAddressBarDropDownItem tsb = null;
tsb = new ShengAddressBarDropDownItem(curNode.DisplayName, curNode.Icon, NodeButtonClicked);
tsb.AddressNode = curNode;
tsb.Overflow = ToolStripItemOverflow.AsNeeded;
dropDown.Items.Add(tsb); //THIS IS THE BIGGEST BOTTLENECK. LOTS OF TIME SPENT IN/CALLING THIS METHOD!
}
addressNode.DropDownMenu = dropDown;
dropDown.LayoutStyle = ToolStripLayoutStyle.Table;
dropDown.MaximumSize = new Size(1000, 400);
dropDown.AddressNode = addressNode;
//不起作用
dropDown.MouseWheel += new MouseEventHandler(ScrollDropDownMenu);
dropDown.MouseEnter += new EventHandler(GiveToolStripDropDownMenuFocus);
return(dropDown);
}
/// <summary>
/// Method to handle when a child has been selected from a node
/// </summary>
/// <param name="sender">Sender of this Event</param>
/// <param name="e">Event Arguments</param>
private void NodeButtonClicked(Object sender, EventArgs e)
{
if (sender.GetType() == typeof(ShengAddressBarDropDownItem) || sender.GetType() == typeof(ShengAddressBarButton))
{
IShengAddressNode addressNode;
if (sender.GetType() == typeof(ShengAddressBarDropDownItem))
{
ShengAddressBarDropDownItem tsb = (ShengAddressBarDropDownItem)sender;
addressNode = tsb.AddressNode;
}
else
{
ShengAddressBarButton tsb = (ShengAddressBarButton)sender;
addressNode = tsb.AddressNode;
}
//set the current node
_currentNode = addressNode;
//cxs
//用不着整个都重新加载，在当前最后一个Item后面加上点的这个就行了
//但是要额外考虑点击的是哪个下拉按钮，如果是中间的，还是要整个刷
ResetBar();
//if (sender.GetType().Equals(typeof(SEAddressBarButton)))
//{
// UpdateBar();
//}
//else
//{
// AddToolStripItemUpdate(ref _currentNode,ButtonPosition.Behind);
//}
//if the selection changed event is handled
if (SelectionChange != null)
{
NodeChangedArgs args = new NodeChangedArgs(_currentNode.UniqueID);
SelectionChange(this, args);
}
return;
}
}
/// <summary>
/// 添加一个地址栏项
/// </summary>
/// <param name="button"></param>
/// <param name="position"></param>
private void AddAddressBarButton(ShengAddressBarButton button, ButtonPosition position)
{
//如果当前显示了最左下拉菜单，就需要直接加在最左下拉菜单下
//如果直接加左边，可能整个地址条是够显示的，就造成这一项出现在最左下拉前面
//并且如果直接加在最左下拉下面，就不用去管是否还有子级了，因为不需要显示那个向下箭头了
if (this.Items.Contains(_overflowButton))
{
ShengAddressBarDropDownItem dropDownItem = new ShengAddressBarDropDownItem(button.Text, button.Image, NodeButtonClicked);
dropDownItem.AddressNode = button.AddressNode;
//_overflowButton.DropDown.Items.Add(dropDownItem);
_overflowDropDown.Items.Add(dropDownItem);
}
else
{
//处理子级，如果需要，需要显示一个向下箭头
BuildChildItem(button);
if (position == ButtonPosition.Behind)
{
this.Items.Add(button);
if (button.DropDownButton != null)
{
this.Items.Add(button.DropDownButton);
}
_buttonList.Add(button);
}
else
{
this.Items.Insert(0, button);
if (button.DropDownButton != null)
{
this.Items.Insert(1, button.DropDownButton);
}
_buttonList.Insert(0, button);
}
}
}
/// <summary>
/// 创建最左下拉菜单
/// </summary>
private void CreateOverflowDropDown()
{
//在最左边添加下拉菜单
if (this.Items.Contains(_overflowButton) == false)
{
this.Items.Insert(0, _overflowButton);
_overflowButton.OwnerChanged += new EventHandler(OverflowDestroyed);
if (this.DropDownRenderer != null)
{
_overflowDropDown.Renderer = this.DropDownRenderer;
}
}
/*
* 把第一项移到前下拉里，然后测试是否还是不够显示，如果还是不够
* 再次把第一项移到前下拉里，如此反复
* 但有一点，需判断第一项是否就是当前项，如果就是当前项，则表示是当前项显示文本太长
* 所以不够显示，需要截断当前项的显示文本
*/
_overflowDropDown.Items.Clear();
while (true)
{
ShengAddressBarButton frontButton = _buttonList[0];
//如果当前节点已经是最右边的节点了
if (_currentNode == frontButton.AddressNode)
{
//计算可以显示的宽度
int itemWidth = 0;
foreach (ToolStripItem item in frontButton.Owner.Items)
{
if (item == frontButton)
{
continue;
}
itemWidth += item.Width;
}
itemWidth = frontButton.Owner.Width - itemWidth - 40;
frontButton.Text = AdjustTextForDisplay(frontButton.Text, itemWidth, frontButton.Font);
break;
////通过截断显示字符串的方式以让它能显示得下
////简单起见，直接截一半，暂时不去测量文本了，截完以后需继续判断，不行再截一半，直到截到最后个字符
//if (frontButton.Text.Length <= 1)
//{
// break;
//}
//else
//{
// frontButton.Text = frontButton.Text.Substring(0, frontButton.Text.Length / 2) + "...";
// if (IsManyNodes())
// {
// CreateOverflowDropDown();
// }
// break;
//}
}
else
{
ShengAddressBarDropDownItem dropDownItem = null;
dropDownItem = new ShengAddressBarDropDownItem(frontButton.Text, frontButton.Image, NodeButtonClicked);
dropDownItem.AddressNode = frontButton.AddressNode;
//把靠左边的第一个项移入最左下拉菜单的顶部
_overflowDropDown.Items.Insert(0, dropDownItem);
this.Items.Remove(frontButton);
if (frontButton.DropDownButton != null)
{
this.Items.Remove(frontButton.DropDownButton);
}
_buttonList.Remove(frontButton);
}
if (IsManyNodes() == false)
{
break;
}
}
}