具有参数的通用类调用

Question

In my form1 I have this method.

public void ChangeView<T>() where T : Control, new()
    {
        if (transitionManager1.IsTransition)
        {
            transitionManager1.EndTransition();
        }

        transitionManager1.StartTransition(BasePanel);
        try
        {

            T find = Find<T>(BasePanel);
            if (find != null)
            {
                find.BringToFront();
            }
            else
            {
                find = new T();
                find.Parent = BasePanel;
                find.Dock = DockStyle.Fill;
                find.BringToFront();
            }

        }
        finally
        {
            transitionManager1.EndTransition();
        }
    }

the problem is when I'm trying to call this method from user control named userC1 that have some parameters in constructor like below

Form1 f;
    public UserC1(Form1 f)   
    {
        InitializeComponent();
        this.f = f;
    }

I call the method as follows in form 1

ChangeView<UserC1>(); 

but above code is an error it says must be a non abstract type with public parameter less constructor in order to use it a parameter in the generic type or method.

how can I over come from this problem. I need that parameters in userC1 constructor.

Answer 1

I edit the code as follows and add a interface to my code as follows...

T Find<T>(Control container) where T : Control
    {
        for (int i = 0; i < container.Controls.Count; i++)
        {
            if (container.Controls[i] is T)
            {
                return (T)container.Controls[i];
            }
        }
        return null;
    }

public void ChangeView<T>(Func<INavigationControl, T> createTInstance) where T : Control, new()
    {
        if (transitionManager1.IsTransition)
        {
            transitionManager1.EndTransition();
        }

        transitionManager1.StartTransition(BasePanel);
        try
        {

            T find = Find<T>(BasePanel);
            if (find != null)
            {
                find.BringToFront();
            }
            else
            {
                if (createTInstance == null)
                    find = new T();
                else
                    find = createTInstance(this);
                find.Parent = BasePanel;
                find.Dock = DockStyle.Fill;
                find.BringToFront();
            }

        }
        finally
        {
            transitionManager1.EndTransition();
        }
    }




public interface INavigationControl
{
    void ChangeView<T>(Func<INavigationControl, T> createTInstance) where T : Control, new();
}

then I added this code to call my change view method

ChangeView(form => new Configurationn(form));

to do this we have to edit the constructor ass follows.

INavigationControl1 f1;
    public YourForm(INavigationControl1 f1) :this(){
        this.f1 = f1;
    }