public async Task AddColumn(ColumnSetting column)
{
if (column.Index == -1)
{
column.Index = _columns.Count;
}
column.Identifier = DateTime.Now.Ticks;
AccountSetting.Column.Add(column);
await AdvancedSettingService.AdvancedSetting.SaveToAppSettings();
var columnModel = new ColumnModel(column, AccountSetting, this);
_columns.Add(columnModel);
await columnModel.Initialize();
}