SelectedItem of DataGrid
I am developing a UI for a host monitoring application that is already being monitored at the database level. I have displayed 2 datagrids in my UI which will populate at runtime. These two datagrids are related by HostID (HostID is a foreign key in LogDatagrid).
The first datagrid displays a list of Host with their status (either running or stopped). I would like to display the log status of the corresponding HostID when the user wants to know the status in detail. How do I achieve this when the user selects the host id in the HostDatagrid? I added my XAML and a screenshot of my interface.
XAML
<DataGrid DataContext="{Binding Path=HostData,NotifyOnTargetUpdated=True,Mode=OneWay}"
AutoGenerateColumns="False" Name="hostDatagrid" Margin="171,32,235,230">
<DataGrid.Columns>
<DataGridTextColumn Header="Host" Width="auto" Binding="{Binding HostID}" />
<DataGridTextColumn Header="Status" Width="auto" Binding="{Binding HostStatus}"/>
</DataGrid.Columns>
</DataGrid>
<DataGrid DataContext="{Binding Path=LogData,NotifyOnTargetUpdated=True,Mode=OneWay}"
AutoGenerateColumns="False" Name="LogDatagrid" Margin="103,108,102,145">
<DataGrid.Columns>
<DataGridTextColumn Header="Host ID" Width="auto" Binding="{Binding HostID}" />
<DataGridTextColumn Header="Logs" Width="auto" Binding="{Binding LogID}" />
<DataGridTextColumn Header="Log Path" Width="auto" Binding="{Binding LogPath}"/>
<DataGridTextColumn Header="Date" Width="auto" Binding="{Binding Date}"/>
<DataGridTextColumn Header="Last Activity" Width="auto" Binding="{Binding LastActivity}"/>
</DataGrid.Columns>
code for LogFile model:
public LogFileModel()
{
}
private int _hostID;
public int HostID
{
get { return _hostID; }
set { _hostID= value; OnpropertyChanged("HostID"); }
}
private string _logid;
public string LogID
{
get { return _logid; }
set { _logid= value; OnpropertyChanged("LogID"); }
}
private string _logpath;
public string LogPath
{
get { return _logPath; }
set { _logPath = value; OnpropertyChanged("LogPath"); }
}
private DateTime _date;
public DateTime Date;
{
get { return _date; }
set { _date= value; OnpropertyChanged("Date"); }
}
private bool _activity;
public bool LastActivity
{
get { return _activity; }
set { _activity= value; OnpropertyChanged("LastActivity"); }
}
Code for LogMile ViewModel:
LogModel _myModel = new LogModel();
private ObservableCollection<LogFileModel> _logFileData = new ObservableCollection<LogFileModel>();
public ObservableCollection<LogFileModel> LogFileData
{
get { return _logFileData; }
set { _logFileData = value; OnPropertyChanged("LogFileData"); }
}
public LogFileViewModel()
{
initializeload();
timer.Tick += new EventHandler(timer_Tick);
timer.Interval = new TimeSpan(0, 0, 3);
timer.Start();
}
~LogFileViewModel()
{
Dispose(false);
}
protected virtual void Dispose(bool disposing)
{
if (!disposed)
{
if (disposing)
{
timer.Stop();
timer.Tick -= new EventHandler(timer_Tick);
}
disposed = true;
}
}
private void timer_Tick(object sender, EventArgs e)
{
try
{
LogFileData.Clear();
initializeload();
}
catch (Exception ex)
{
timer.Stop();
Console.WriteLine(ex.Message);
}
}
private void initializeload()
{
try
{
DataTable table = _myModel.getData();
for (int i = 0; i < table.Rows.Count; ++i)
LogFileData.Add(new LogFileModel
{
HostID= Convert.ToInt32(table.Rows[i][0]),
LogID = table.Rows[i][1].ToString(),
LogPath = table.Rows[i][2].ToString(),
Date = Convert.ToDateTime(table.Rows[i][3]),
LastAcivity= table.Rows[i][4].ToString(),
});
}
catch (Exception e)
{
Console.WriteLine(e.Message);
}
}
public event PropertyChangedEventHandler PropertyChanged;
private void OnPropertyChanged(string propertyname)
{
var handler = PropertyChanged;
if (handler != null)
handler(this, new PropertyChangedEventArgs(propertyname));
}
public class LogModel
{
public DataTable getData()
{
DataTable ndt = new DataTable();
SqlConnection sqlcon = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
sqlcon.Open();
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM [LocalDB].[dbo].[LogFiles]", sqlcon);
da.Fill(ndt);
da.Dispose();
sqlcon.Close();
return ndt;
}
}
}
}
I followed the same pattern for the Host Model and ViewModel.
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You will need to have the following in your code view model
A SelectedItem that will hold the selected item in the first DataGrid. A HostData collection that contains all of your hosts. Empty log data collection that will display logs for a specific host
//populate with all your hosts and this will bind to your first datagrid
private ObservableCollection<HostModel> _hostData= new ObservableCollection<Host>();
public ObservableCollection<HostModel> HostData
{
get { return _hostData; }
set { _hostData= value; OnPropertyChanged("HostData"); }
}
//populate with all the logs for the selected item and bind this to your second datagrid
private ObservableCollection<LogFileModel> _logFileData = new ObservableCollection<LogFileModel>();
public ObservableCollection<LogFileModel> LogFileData
{
get { return _logFileData; }
set { _logFileData = value; OnPropertyChanged("LogFileData"); }
}
//when the user selects an item in the first datagrid this property will hold the value
//so you will bind it to the selected item property of your first datagrid
private Host _selectedHost; //initialise to avoid null issues
public HostModelSelectedHost
{
get{ return _selectedItem; }
set
{
//call a method to populate you second collection
_selectedHost = value;
logFileData = GetLogsForSelectedHost(_selectedHost);
OnPropertyChanged("SelectedHost");
{
}
//the method for populating your second collection could look like this
private ObservableCollection<LogFileModel> GetLogsForSelectedHost(_selectedHost)
{
ObservableCollection<LogFileModel> filteredLogs = new ObservableCollection<LogFileModel>;
filteredLogs = //fill the collection with all the logs that match the host ID of
//your selected item
return filteredLogs ;
}
I'm not sure in your code which class it is, but I hope the above code can show you a way to do it.
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Do something like this:
create a method in your main datamodel called lookup. Search has a query to find your other data file that stores a data log and returns a data table. Then add a CellClick listener method for your host status Datagrid and do something like below. Hope I don't know enough about what you need.
private void hostDatagrid_CellClick(object sender, DataGridViewCellEventArgs e)
{
string cellValue = hostDatagrid[e.ColumnIndex,e.RowIndex].Value.ToString();
LogFileViewModel logFileViewModel = new LogFileViewModel();
DataTable table = logFileViewModel.search(cellValue);
BindingSource bs = new BindingSource();
bs.DataSource = table;
logDataGrid.Datasource = table;
logDataGrid.Update();
logDataGrid.Refresh();
}
// and add this method to LogFileViewModel
public DataTable Search(string hostID)
{
DataTable ndt = new DataTable();
SqlConnection sqlcon = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConnectionString"].ConnectionString);
sqlcon.Open();
SqlDataAdapter da = new SqlDataAdapter("SELECT * FROM whatever WHERE hostid ="+hostID, sqlcon);
da.Fill(ndt);
da.Dispose();
sqlcon.Close();
return ndt;
}
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1) Bind a property SelectedItem
to Host
in your ViewModel from yourHost
DataGrid
SelectedItem = {Binding SelectedHost, Mode=TwoWay, UpdateSourceTrigger=PropertyChanged}
2) Assuming LogData is an ObservableCollection, in the customizer for the property, SelectedHost
update the LogData to display the logs for Host
.
public Host SelectedHost {
get;
set {
SelectedHost = value;
UpdateLogData();
OnPropertyChanged("SelectedHost");
}
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