/// <summary>
/// 子类在 Measure 时，调用此方法来连接到 TreeGrid，并同步一些必要的属性。
/// </summary>
internal void ConnectToGrid()
{
if (_treeGrid == null)
{
_treeGrid = this.GetVisualParent<TreeGrid>();
if (_treeGrid != null)
{
_columns = _treeGrid.Columns;
InternalCollectionChangedEventManager.AddListener(_columns, this);
}
}
}
internal TreeGridSelectionModel(TreeGrid owner, bool isChecking)
{
this.Owner = owner;
this.SelectedItems = new SelectedItemsAPI { _model = this };
this.IsChecking = isChecking;
}
protected override void OnIsItemsHostChanged(bool oldIsItemsHost, bool newIsItemsHost)
{
base.OnIsItemsHostChanged(oldIsItemsHost, newIsItemsHost);
if (newIsItemsHost)
{
var owner = this.TreeGrid;
if (owner != null)
{
IItemContainerGenerator itemContainerGenerator = owner.ItemContainerGenerator;
if (itemContainerGenerator != null && itemContainerGenerator == itemContainerGenerator.GetItemContainerGeneratorForPanel(this))
{
owner.RowsPanel = this;
return;
}
}
}
else
{
if (this._owner != null && this._owner.RowsPanel == this)
{
this._owner.RowsPanel = null;
}
this._owner = null;
}
}
//protected override void ClearContainerForItemOverride(DependencyObject element, object item)
//{
// var cell = element as TreeGridCell;
// base.ClearContainerForItemOverride(element, item);
// this.ReserveEditingContent(cell);
//}
//private void ReserveEditingContent(TreeGridCell cell)
//{
// //IsEditing：把编辑控件存储下来。
// var row = this.Row;
// if (row != null)
// {
// var grid = row.TreeGrid;
// if (grid != null && this.DataContext == grid.EditingItem)
// {
// //非回收模式下，需要把
// if (!grid.IsRecycleMode)
// {
// if (grid.EditingMode == TreeGridEditingMode.Row || cell.Column == grid.EditingColumn)
// {
// if (this._editingElements == null)
// {
// this._editingElements = new Dictionary<TreeGridColumn, UIElement>();
// }
// this._editingElements[cell.Column] = cell.Content as UIElement;
// }
// }
// }
// }
//}
private void RestoreEditingContent(TreeGridCell cell, TreeGridColumn column, TreeGrid grid)
{
////非回收模式下，为了返回原来的焦点，需要使用之前的编辑控件。
//if (!grid.IsRecycleMode)
//{
// //如果之前已经生成了编辑控件，则使用老的控件，这样可以继续之前的编辑信息。
// if (this._editingElements != null)
// {
// UIElement content = null;
// if (this._editingElements.TryGetValue(column, out content))
// {
// cell.UpdateContent(content);
// //column.PrepareElementForEdit(content as FrameworkElement, null);
// //var res = content.Focus();
// //Debug.WriteLine(" content.IsVisible:" + content.IsVisible
// // + " content.Focus():" + res
// // + " KeyboardFocus:" + Keyboard.FocusedElement.GetType().FullName
// // );
// this._editingElements.Remove(column);
// }
// }
//}
}
/// <summary>
/// 使用此方法可以把当前 View 的控件替换为所给的控件。
/// <remarks>
/// 使用场景：如果期望完全使用全新的表格控件，可以使用这个方法来重新设置视图与控件的绑定。
/// 例如：要实现动态列需求时，需要不断地重新生成表格控件。
/// </remarks>
/// </summary>
/// <param name="treeGrid"></param>
public void ReplaceControl(TreeGrid treeGrid)
{
var oldControl = this.Control;
oldControl.ReplaceInParent(treeGrid);
if (oldControl.ContextMenu != null) { treeGrid.ContextMenu = oldControl.ContextMenu; }
_listEditor.SetControl(treeGrid);
this.SetControl(treeGrid);
_listEditor.NotifyContextDataChanged();
}
/// <summary>
/// Creates the monitor with the tree to be processed.
/// </summary>
/// <param name="tree">The tree that renders the monitored
/// items.</param>
/// <exception cref="ArgumentNullException">If <paramref name="tree"/>
/// is a null reference.</exception>
public ItemMonitor(TreeGrid tree)
{
if (tree == null) throw new ArgumentNullException("tree");
this.tree = tree;
}
/// <summary>
/// 连接到可视父元素，连接成功，则返回 true。
/// </summary>
/// <returns></returns>
private bool TryConnect()
{
if (!this.IsConnected)
{
this._cellsPresenter = ItemsControl.GetItemsOwner(this) as TreeGridCellsPresenter;
if (this._cellsPresenter != null)
{
this._cellsPresenter.InternalItemsHost = this;
var row = this._cellsPresenter.Row;
if (row != null)
{
row.CellsPanel = this;
this._treeGrid = row.TreeGrid;
if (this._treeGrid != null)
{
InternalCollectionChangedEventManager.AddListener(this._treeGrid.Columns, this);
this._rowsPanel = this._treeGrid.RowsPanel;
//分组显示时，RowsPanel 为 null，也不能进行虚拟化操作。
this._isVirtualizing = this._rowsPanel != null && this._treeGrid.IsColumnsVirtualizingEnabled;
this._isRecycleMode = this._treeGrid.IsRecycleMode;
}
}
}
}
return this.IsConnected;
}
private void Disconnect()
{
if (this.IsConnected)
{
InternalCollectionChangedEventManager.RemoveListener(this._treeGrid.Columns, this);
this._rowsPanel = null;
this._treeGrid = null;
var row = this._cellsPresenter.Row;
if (row != null) { row.CellsPanel = null; }
this._cellsPresenter.InternalItemsHost = null;
this._cellsPresenter = null;
}
}
