从另一个类调用Window_Loaded事件

Question

My MainWindow.xaml.cs class includes following Window_Loaded Event:

public void Window_Loaded(object sender, RoutedEventArgs e)
{
    SQLClass sqlclass = new SQLClass();
    sqlclass.initSQL(dataGrid1);
}

So I'm calling this initSql(Datagrid dataGrid) method from the SQLClass , which actually binds my dataGrid to the Sql table.

public void initSQL(DataGrid dataGrid)
{
    AppDomain.CurrentDomain.SetData("DataDirectory", "C:\\Users\\Osman\\");
    try
    {
        using (SqlConnection cn = new SqlConnection("Data Source=.\\SQLExpress;Initial Catalog=FinalApplication1;Integrated Security=True;"))
        {

            cn.Open();
            SqlDataAdapter adap = new SqlDataAdapter("SELECT Time, Condition FROM Status", cn);
            System.Data.DataSet ds = new System.Data.DataSet();
            adap.Fill(ds, "Status");
            dataGrid.DataContext = ds.Tables["Status"].DefaultView;
        }
    }
    catch (Exception ex)
    {
        MessageBox.Show("Error\n" + ex.Message, "Error", MessageBoxButton.OK, MessageBoxImage.Error);
    }
}

This works perfectly on a startup, but when I want to update the dataGrid after inserting a value to the Sql table, I'm then calling the Window_Loaded method from from my BluetoothLE class:

public class BluetoothLE
{
    private void dispatcherTimer_Tick(object sender, EventArgs e)
    {
        dispatcherTimer.Stop();
        MainWindow mainwin = new MainWindow();
        mainwin.Window_Loaded(this, null);
    }
}

The issue is that the dataGrid does not update in this case. The Window_Loaded method is triggered, but it does not update the dataGrid. What's actually wrong here ?.

Answer 1

your are creating a new instance of your main window where you don't show rather than updating datagrid of your current MainWindow . Try:

private void Update()
{
    //enter datagrid functionality you have in window load event
}

public class BluetoothLE
{
    private void dispatcherTimer_Tick(object sender, EventArgs e)
    {
        dispatcherTimer.Stop();
        Update();
    }
}

Answer 2

The code:

MainWindow mainwin = new MainWindow();
mainwin.Window_Loaded(this, null);

will not work, you need to call Window_Loaded on the current instance of MainWindow , creating a new instance (with the new MainWindow() line) won't affect the window that's displayed on the screen.

I don't know where you create your BluetoothLE class but it needs to have a reference to the MainWindow instance so it can call methods on it. Something like the following:

public class BluetoothLE
{
    private MainWindow windowInstance;
    public BluetoothLE(MainWindow windowInstance) {
        this.windowInstance = windowInstance;
    }
    private void dispatcherTimer_Tick(object sender, EventArgs e)
    {
        dispatcherTimer.Stop();
        windowInstance.Window_Loaded(this, null);
    }
}

And if you create BluetoothLE from inside MainWindow :

var bluetooth = new BluetoothLE(this);

If you wanted to get rid of that dependence (you probably should in the long run) you might want to use C# events, but that's another story.

Also pull out your update code into a separate method called UpdateGrid() or something and call it from the Window_Load event and other places you need to update, Window_Load shouldn't be used to update the UI from elsewhere.

Answer 3

((MainWindow)Application.Current.MainWindow).Window_Loaded(this, null);

这应该做您想要做的事情，尽管这是一种非常丑陋的方式。