WPF: set log level and refresh collection after changing - wpf

Question

So I have form that show my Application Log.
This is my Log model:
public class LogEntry : IComparable<LogEntry>
{
public string DateTime { get; set; }
public int Index { get; set; }
public string Source { get; set; }
public Level Level { get; set; }
public string Message { get; set; }
public int CompareTo(LogEntry other)
{
return DateTime.CompareTo(other.DateTime);
}
}
public enum Level
{
All = 0,
Debug,
Info,
Warn,
Error,
Fatal,
Off
}
Log Helper
This is my LogHelper class that add the current LogEvent according the level that the user selected:
public static class LogHelper
{
public static ObservableCollection<LogEntry> LogEntries { get; set; }
public static bool AddLogToList { get; set; }
private static int _level;
private static int _index;
private static string _formatPattern = "yyyy-MM-dd HH:mm:ss,fff";
public static void SetLevel(Level level)
{
_level = (int)level;
}
public static void AddLog(Level level, string message, string className, string methodName)
{
if (LogEntries == null)
LogEntries = new ObservableCollection<LogEntry>();
if (AddLogToList)
{
int levelValue = (int)level;
if (levelValue >= _level)
{
Application.Current.Dispatcher.Invoke(new Action(() =>
{
if (LogEntries.Count == 1000)
LogEntries.RemoveAt(LogEntries.Count - 1);
LogEntry logEntry = new LogEntry()
{
DateTime = DateTime.Now.ToString(_formatPattern),
Index = _index++,
Level = level,
Source = className + "\\" + methodName,
Message = message.Trim()
};
LogEntries.Insert(0, logEntry);
}));
}
}
}
}
So I am add LogEvent into my list that contains up ti 1000 entries.
Now I want to be able to filter and show my only the relevant LogEvent Level.
So I added ComboBox with all my LogEvent levels and subscribe to its SelectionChanged event:
private void cbLogLevel_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
{
int index = cbLogLevel.SelectedIndex;
LogHelper.SetLevel((Level)index);
lvLogger.ItemsSource = LogHelper.LogEntries.Where(m => m.Level == (Level)index).ToList();
}
So after this SelectionChanged event I can see the relevant LogEvent level but my only issue is the new LogEvent not shows.
Maybe I need kind of refresh to my collection or something else ?

Answer 1

You are creating a new List<LogEntry> and setting the ItemsSource property to this one in your event handler. This means that lvLogger will no longer be connected to the ObservableCollection.
Instead of resetting the ItemsSource, you could filter the view:
private void cbLogLevel_SelectionChanged(object sender, System.Windows.Controls.SelectionChangedEventArgs e)
{
int index = cbLogLevel.SelectedIndex;
Level level = (Level)index;
LogHelper.SetLevel(level);
var collectionView = CollectionViewSource.GetDefaultView(lvLogger.ItemsSource);
collectionView.Filter = x =>
{
LogEntry logEntry = x as LogEntry;
return logEntry != null && logEntry.Level == level;
};
}