private bool BeginCellEdit(DataGridEditingTriggerInfo editingTriggerInfo)
{
//
if (this.CurrentColumnIndex == -1 || !GetRowSelection(this.CurrentRowIndex))
{
//
return false;
}
Debug.Assert(this.CurrentColumnIndex >= 0);
Debug.Assert(this.CurrentColumnIndex < this.Columns.Count);
Debug.Assert(this.CurrentRowIndex >= -1);
Debug.Assert(this.CurrentRowIndex < this._rowCount);
Debug.Assert(this._editingRow == null || this.EditingRowIndex == this.CurrentRowIndex);
Debug.Assert(!GetColumnEffectiveReadOnlyState(this.CurrentColumn));
Debug.Assert(this.CurrentColumn.Visibility == Visibility.Visible);
if (this._editingColumnIndex != -1)
{
// Current cell is already in edit mode
Debug.Assert(this._editingColumnIndex == this.CurrentColumnIndex);
//
return true;
}
//
DataGridRow dataGridRow = this._editingRow;
if (dataGridRow == null)
{
if (IsRowDisplayed(this.CurrentRowIndex))
{
dataGridRow = GetDisplayedRow(this.CurrentRowIndex);
}
else
{
dataGridRow = GenerateRow(this.CurrentRowIndex);
}
}
Debug.Assert(dataGridRow != null);
DataGridCell dataGridCell = dataGridRow.Cells[this.CurrentColumnIndex];
DataGridCellEditingCancelEventArgs e = new DataGridCellEditingCancelEventArgs(this.CurrentColumn, dataGridRow, dataGridCell.Content as FrameworkElement, editingTriggerInfo);
OnBeginningCellEdit(e);
if (e.Cancel)
{
//
return false;
}
if (this._editingRow == null && !BeginRowEdit(dataGridRow))
{
//
return false;
}
Debug.Assert(this._editingRow != null);
Debug.Assert(this.EditingRowIndex == this.CurrentRowIndex);
this._editingColumnIndex = this.CurrentColumnIndex;
this._editingTriggerInfo = editingTriggerInfo;
this._editingRow.Cells[this.CurrentColumnIndex].ApplyCellState(true /*animate*/);
PopulateCellContent(false /*forceTemplating*/, true /*isCellEdited*/, this.CurrentColumn, dataGridRow, dataGridCell);
//
return true;
}
/// <summary>
/// Raises the BeginningCellEdit event.
/// </summary>
protected virtual void OnBeginningCellEdit(DataGridCellEditingCancelEventArgs e)
{
EventHandler<DataGridCellEditingCancelEventArgs> handler = this.BeginningCellEdit;
if (handler != null)
{
handler(this, e);
}
}