MVP-从视图到演示者获取数据

Question

I'm trying to get some practice implementing the MVP pattern in a simple C# WinForms application. On the left of the view is a tree view with a list of the files saved by the application; on the right of the view is a DataGridView for displaying whichever file is clicked in the tree view, or for typing into to save as a new file. The files are simply Dictionary objects written to disk with BinaryFormatter.

I created an interface for the view:

public interface IMappingsView
{
    event EventHandler SaveMapping;
    event EventHandler NewMapping;
    event EventHandler<DeleteArgs> DeleteMapping;
    event EventHandler PasteData;
    event EventHandler NodeClicked;
}

The delete button on the view has the following click event handler:

private void buttonDeleteMapping_Click(object sender, EventArgs e)
{
    var node = treeView1.SelectedNode.Text;
    var args = new DeleteArgs(Path.Combine(RootDir,node));

    if (DeleteMapping != null)
    {
        DeleteMapping(this, args);
        dataGridView1.Rows.Clear();
        RefreshTreeView();
    }
}

What is the best way to to pass information from the view to the presenter? I feel as though needing custom event arguments for every scenario is very wrong.

Answer 1

Make the data you want available available via the interface as a property.

Assuming you have a firstName and lastName field that you want exposed...

public interface IMappingsView
{
    event EventHandler SaveMapping;
    event EventHandler NewMapping;
    event EventHandler<DeleteArgs> DeleteMapping;
    event EventHandler PasteData;
    event EventHandler NodeClicked;
    string FirstName {get;set;}
    string LastName {get;set;}
}

Then in your form that implements the interface,

string FirstName {
    get {
        return textFirstName.Text;
    }
    set { 
        textFirstName.Text = value;
    }
}

as an example.