GDI+ Create TextBox with text and be able to Drag Drop around pictureBox

[magefesa]

Based on a sample found on Mr. John McIlhinney's .NET Developer Blog I'm triyng to modify the sample to achieve this :

- Create Rectangle on a PictureBox via GDI+ and inside a textbox with user desired text. Also, and more important, the user must be able to drag drop/move the Box throught the image.

https://docs.google.com/open?id=0By3...GE5Q0pKWmZBMEE

Here is my code, modifying the sample wit a class called TxRectangle... But the drag drop does'nt works...any help please ???

Thanks to Mr. for your help and advices.

Frank

[formlesstree4]

Just curious, is this homework?

[dday9]

But the drag drop does'nt works

Take a look at JMcilhinney's submission on drag and drop in window's forms here

https://docs.google.com/open?id=0By3...GE5Q0pKWmZBMEE

Unfortunately, I personally do NOT download any files. I suggest that you post the relevant code that you're having troubles with.

[magefesa]

Not homework, this is a sample project from Mr JMcilhinney's blog. I ve modified it.

I can asure is free virus code. The problem with GDI is that drag and drop is not easy as when you do that with CONTROLS.

Any ideas pleasE ??

Thanks in advance to all for your answers and time dedicated.

[jmcilhinney]

Instead of using a List(Of Rectangle) as I do in my blog post, define your own class that has properties for the Rectangle with which to bound the text, the String containing the text and any other formatting information you want to support. You then do everything as I did before but you work with the Rectangle property of each item rather than each item itself being a Rectangle.

[magefesa]

Dear Jm.

Is what i ¡ve done on my sample uploaded, as you can see there is a class called TxRectangle.

Public Class TxRectangle
    Private m_rec As Rectangle
    Private m_Tx As String
   
    Public Property Rec As Rectangle
        Get
            Return m_rec
        End Get
        Set(ByVal value As Rectangle)
            m_rec = value
        End Set
    End Property
    Public Property Tx As String
        Get
            Return m_Tx
        End Get
        Set(ByVal value As String)
            m_Tx = value
        End Set
    End Property


End Class

All works fine, except the event :

Private Sub PictureBox1_MouseMove(ByVal sender As Object, _
                                  ByVal e As MouseEventArgs) Handles PictureBox1.MouseMove
        If Control.MouseButtons = Windows.Forms.MouseButtons.Left Then
            If Me.drawMode Then
                Me.InvalidateRectangle(Me.GetRectangle(Me.startPoint, Me.endPoint))
                Me.endPoint = e.Location
                Me.InvalidateRectangle(Me.GetRectangle(Me.startPoint, Me.endPoint))
                Me.PictureBox1.Update()

            ElseIf Me.selectedBoxIndex <> -1 Then
                Dim box As Rectangle = Me.txboxes(Me.selectedBoxIndex).Rec
                Dim location As Point = e.Location

                Me.InvalidateRectangle(Me.txboxes(Me.selectedBoxIndex))

                box.Offset(location.X - Me.startPoint.X, _
                    location.Y - Me.startPoint.Y)
                ' Me.txboxes(Me.selectedBoxIndex) = box
                'txboxes(Me.selectedBoxIndex).Rec.Offset(location.X - Me.startPoint.X, _
                '          location.Y - Me.startPoint.Y)



                Me.startPoint = location

                Me.InvalidateRectangle(Me.txboxes(Me.selectedBoxIndex))
                Me.PictureBox1.Update()
            End If
        End If
    End Sub

There are no errors, but the rectangle is not dragged.... PLEASE... please.... hheeeeeellllp sir !!

Frank

[jmcilhinney]

Rectangle is a value type, which means that a variable of that type contains the object itself rather than a reference to the object. As such, when you assign a value from one variable to another, you are creating a copy of the object. Here:

Dim box As Rectangle = Me.txboxes(Me.selectedBoxIndex).Rec

you are making such an assignment so 'box' contains a copy of the Rectangle. That means that here:

box.Offset(location.X - Me.startPoint.X, location.Y - Me.startPoint.Y)

you are offsetting the copy, which has no effect on the original. Your mistake was commenting out this line:

' Me.txboxes(Me.selectedBoxIndex) = box

That line copies the copy, which has been offset, back over the original. That whole section of code should loon like this:

            ElseIf Me.selectedBoxIndex <> -1 Then
                Dim txbox As TxRectangle = Me.txboxes(Me.selectedBoxIndex)
                Dim box As Rectangle = txbox.Rec
                Dim location As Point = e.Location

                Me.InvalidateRectangle(box)

                box.Offset(location.X - Me.startPoint.X, _
                    location.Y - Me.startPoint.Y)
                txbox.Rec = box

                Me.startPoint = location

                Me.InvalidateRectangle(box)
                Me.PictureBox1.Update()
            End If
        End If
    End Sub

[magefesa]

YES !! !! Finally achieved !!!!

Thanks to all !!!!!

One more thing i spossible ??

I would like to RESIZE a drawn box.... I know if a box is clicked, but how to "resize it " ??

[jmcilhinney]

A big part of programming is using things that you already know in new situations, and this is no different. You already have all you need. To move a box you have to detect a mouse event, determine where it is, if it is on a box and which box it is, then redraw the box with its new bounds. What you're asking for is exactly the same pattern. The only difference will be that the Size of the new Rectangle will be different instead of or as well as the Location, where in the existing example only the Location is different.