private unsafe bool WmSelChanging(ref Message m)
{
if (!bEnableSelectEvents)
{
return(false);
}
Native.NMTREEVIEW *nmtv = (Native.NMTREEVIEW *)m.LParam;
TreeNode node = TreeNode.FromHandle(this, nmtv->itemNew.hItem);
OnBeforeMultiSelectStart(new CMSTreeViewMultiSelectEventArgs(SelectedNodes, TreeViewAction.Unknown));
bool bIsSelected = true;
CMSTreeViewCancelEventArgs e = new CMSTreeViewCancelEventArgs(node, false, bIsSelected, TreeViewAction.Unknown);
OnBeforeSelect(e);
if (e.Cancel)
{
// user canceled operation, cancel changing of the selection
m.Result = (IntPtr)1;
return(true);
}
return(false);
}
private bool SetFocusedItem(TreeNode node, bool bSelect, TreeNode oldNode, TreeViewAction action)
{
CMSTreeViewCancelEventArgs e = new CMSTreeViewCancelEventArgs(node, false, bSelect, action);
OnBeforeSelect(e);
if (e.Cancel)
{
return(false);
}
// temporary disable OnXXXSelect events
this.bEnableSelectEvents = false;
IntPtr hItem = SetFocusedItem(node);
if (bSelect)
{
AddSelectedItem(node);
}
else
{
RemoveSelectedItem(node);
}
SetSelectedState(node, bSelect);
// enable OnXXXSelect events
this.bEnableSelectEvents = true;
OnAfterSelect(new CMSTreeViewEventArgs(node, bSelect, action));
return(true);
}
protected virtual void OnBeforeSelect(CMSTreeViewCancelEventArgs e)
{
if (!bEnableSelectEvents)
{
return;
}
#if MSTREE_TRACE
Debug.Write("EVENT: " + traceCount.ToString() + (e.Selected ? " OnBeforeSelect:" : " OnBeforeUnselect:"));
Debug.Write(" node=" + (e.Node != null ? "\"" + e.Node.Text + "\"": "null"));
Debug.WriteLine(" action=" + e.Action);
#endif
TreeViewCancelEventArgs newE = new TreeViewCancelEventArgs(e.Node, e.Cancel, e.Action);
if (e.Selected)
{
if (onBeforeSelect != null)
{
onBeforeSelect(this, newE);
}
}
else
{
if (onBeforeUnselect != null)
{
onBeforeUnselect(this, newE);
}
}
e.Cancel = newE.Cancel;
}
private unsafe bool TvnSelectItem(ref Message m)
{
Native.TV_ITEM *item = (Native.TV_ITEM *)m.LParam;
// Check for invalid node handle
if (item == null || item->hItem == IntPtr.Zero)
{
return(false);
}
if ((item->mask & Native.TVIF_STATE) == 0 || (item->stateMask & Native.TVIS_SELECTED) == 0)
{
return(false);
}
TreeNode node = TreeNode.FromHandle(this, item->hItem);
Debug.Assert(node != null);
bool bIsSelected = (item->state & Native.TVIS_SELECTED) != 0;
bool bDontFireEvents = bIsSelected == this.selectedNodes.Contains(node);
if (!bDontFireEvents)
{
CMSTreeViewCancelEventArgs e = new CMSTreeViewCancelEventArgs(node, false, bIsSelected, TreeViewAction.Unknown);
OnBeforeSelect(e);
if (e.Cancel)
{
m.Result = (IntPtr)1;
return(true);
}
if (bIsSelected)
{
AddSelectedItem(node);
}
else
{
RemoveSelectedItem(node);
}
}
base.WndProc(ref m);
if (!bDontFireEvents)
{
OnAfterSelect(new CMSTreeViewEventArgs(node, bIsSelected, TreeViewAction.Unknown));
}
return(true);
}
