Dnd.cs

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//-----------------------------------------------------------------------------
// wx.NET/Samples - Dnd.cs
//
// wx.NET "Dnd" sample.
//
// Written by Alexander Olk (xenomorph2@onlinehome.de)
// (C) 2003 Alexander Olk
// Licensed under the wxWidgets license, see LICENSE.txt for details.
//
// $Id: Dnd.cs,v 1.13 2010/06/05 13:10:56 harald_meyer Exp $
//-----------------------------------------------------------------------------

using System;
using System.Drawing;
using System.Runtime.InteropServices;

using wx;

namespace wx.SampleDnd
{
    public class DNDText : TextDropTarget
    {
        private ListBox myOwner;

        //---------------------------------------------------------------------

        public DNDText(ListBox myOwner)
            : base()
        {
            this.myOwner = myOwner;
        }

        //---------------------------------------------------------------------

        public override bool OnDropText(int x, int y, string text)
        {
            myOwner.Append(text);
            return true;
        }
    }

    //---------------------------------------------------------------------

    public class DNDFile : FileDropTarget
    {
        private ListBox myOwner;

        //---------------------------------------------------------------------

        public DNDFile(ListBox myOwner)
            : base()
        {
            this.myOwner = myOwner;
        }

        //---------------------------------------------------------------------

        public override bool OnDropFiles(int x, int y, string[] filenames)
        {
            string str = filenames.Length + " files dropped";
            myOwner.Append(str);

            for (int i = 0; i < filenames.Length; i++)
            {
                myOwner.Append(filenames[i]);
            }

            return true;
        }
    }

    //---------------------------------------------------------------------     

    public class DndFrame : Frame
    {
        enum Cmd
        {
            Menu_Drag, Menu_DragMoveDef, Menu_DragMoveAllow, Menu_About, Menu_Quit,
            Menu_Clear, Menu_Help, Menu_Copy, Menu_Paste
        }

        private ListBox m_ctrlText = null;
        private ListBox m_ctrlFile = null;

        private TextCtrl m_ctrlLog = null;

        private bool m_moveByDefault = false;
        private bool m_moveAllow = true;

        public string m_strText;

        //---------------------------------------------------------------------

        public DndFrame(string title, Point pos, Size size)
            : base(title, pos, size)
        {
            // Set the window icon and status bar

            Icon = new wx.Icon("../Samples/Dnd/mondrian.png");

            CreateStatusBar();
            StatusText = "Welcome to the Dnd Sample!";

            // Set up a menu

            Menu fileMenu = new Menu();
            fileMenu.Append((int)Cmd.Menu_Drag, "&Test drag...");
            fileMenu.AppendCheckItem((int)Cmd.Menu_DragMoveDef, "&Move by default", "");
            fileMenu.AppendCheckItem((int)Cmd.Menu_DragMoveAllow, "&Allow moving", "");
            fileMenu.AppendSeparator();
            fileMenu.Append((int)Cmd.Menu_Quit, "E&xit\tCtrl-Q");

            Menu logMenu = new Menu();
            logMenu.Append((int)Cmd.Menu_Clear, "Clear\tCtrl-L");

            Menu helpMenu = new Menu();
            helpMenu.Append((int)Cmd.Menu_Help, "&Help");
            helpMenu.AppendSeparator();
            helpMenu.Append((int)Cmd.Menu_About, "&About");

            Menu clipMenu = new Menu();
            clipMenu.Append((int)Cmd.Menu_Copy, "&Copy text\tCtrl-C");
            clipMenu.Append((int)Cmd.Menu_Paste, "&Paste text\tCtrl-V");

            wx.MenuBar menuBar = new wx.MenuBar();
            menuBar.Append(fileMenu, "&File");
            menuBar.Append(logMenu, "&Log");
            menuBar.Append(clipMenu, "&Clipboard");
            menuBar.Append(helpMenu, "&Help");

            MenuBar = menuBar;

            Size asize = new Size(300, 200);
            Size bsize = new Size(600, 100);

            string[] strFile = { "Drop files here!" };
            string[] strText = { "Drop text on me" };

            m_ctrlFile = new ListBox(this, -1, wxDefaultPosition, asize, strFile, wx.WindowStyles.LB_HSCROLL | wx.WindowStyles.LB_ALWAYS_SB);

            m_ctrlText = new ListBox(this, -1, wxDefaultPosition, asize, strText, wx.WindowStyles.LB_HSCROLL | wx.WindowStyles.LB_ALWAYS_SB);

            m_ctrlLog = new TextCtrl(this, -1, "", wxDefaultPosition, bsize, wx.WindowStyles.TE_MULTILINE | wx.WindowStyles.TE_READONLY | wx.WindowStyles.BORDER_SUNKEN);

            Log.SetActiveTarget(m_ctrlLog);
            Log.AddTraceMask("focus");

            m_ctrlFile.DropTarget = new DNDFile(m_ctrlFile);
            m_ctrlText.DropTarget = new DNDText(m_ctrlText);

            BoxSizer main_sizer = new BoxSizer(Orientation.wxVERTICAL);
            BoxSizer h_sizer = new BoxSizer(Orientation.wxHORIZONTAL);

            h_sizer.Add(m_ctrlFile, 1, wx.SizerFlag.wxALL, 5);
            h_sizer.Add(m_ctrlText, 1, wx.SizerFlag.wxALL, 5);
            main_sizer.Add(h_sizer, 0, wx.SizerFlag.wxALL, 0);
            main_sizer.Add(m_ctrlLog, 1, wx.SizerFlag.wxALL, 5);
            main_sizer.Add(new BoxSizer(Orientation.wxHORIZONTAL), 1, wx.SizerFlag.wxALL, 5);

            AutoLayout = true;
            SetSizer(main_sizer, true);

            main_sizer.Fit(this);
            main_sizer.SetSizeHints(this);

            menuBar.Check((int)Cmd.Menu_DragMoveAllow, true);

            // Set up the event table

            EVT_MENU((int)Cmd.Menu_Quit, new EventListener(OnQuit));
            EVT_MENU((int)Cmd.Menu_About, new EventListener(OnAbout));
            EVT_MENU((int)Cmd.Menu_Drag, new EventListener(OnDrag));
            EVT_MENU((int)Cmd.Menu_DragMoveDef, new EventListener(OnDragMoveByDefault));
            EVT_MENU((int)Cmd.Menu_DragMoveAllow, new EventListener(OnDragMoveAllow));
            EVT_MENU((int)Cmd.Menu_Help, new EventListener(OnHelp));
            EVT_MENU((int)Cmd.Menu_Clear, new EventListener(OnLogClear));
            EVT_MENU((int)Cmd.Menu_Copy, new EventListener(OnCopy));
            EVT_MENU((int)Cmd.Menu_Paste, new EventListener(OnPaste));

            EVT_SIZE(new EventListener(OnSize));

            EVT_PAINT(new EventListener(OnPaint));

            EVT_UPDATE_UI((int)Cmd.Menu_DragMoveDef, new EventListener(OnUpdateUIMoveByDefault));
            EVT_UPDATE_UI((int)Cmd.Menu_Paste, new EventListener(OnUpdateUIPasteText));

            EVT_LEFT_DOWN(new EventListener(OnLeftDown));
            EVT_RIGHT_DOWN(new EventListener(OnRightDown));

            Log.LogMessage("DnD sample started..");

            m_strText = "wx.NET drag & drop works :-)";
        }

        //---------------------------------------------------------------------

        public void OnQuit(object sender, wx.Event e)
        {
            Close();
        }

        //---------------------------------------------------------------------


        public void OnAbout(object sender, wx.Event e)
        {
            string msg = "This is the About dialog of the dnd sample.";
            wx.MessageDialog.ShowModal(this, msg, "About Dnd", wx.WindowStyles.DIALOG_OK | wx.WindowStyles.ICON_INFORMATION);
        }

        //---------------------------------------------------------------------

        public void OnSize(object sender, Event e)
        {
            Refresh();

            e.Skip();
        }

        //---------------------------------------------------------------------

        public void OnPaint(object sender, Event e)
        {
            Size cs = ClientSize;

            PaintDC dc = new PaintDC(this);

            dc.Font = new Font(24, FontFamily.wxDECORATIVE, FontStyle.wxNORMAL, FontWeight.wxNORMAL, false, "charter");
            dc.DrawText("Drag text from here!", 100, cs.Height - 50);

            dc.Dispose();
        }

        //---------------------------------------------------------------------

        public void OnUpdateUIMoveByDefault(object sender, Event e)
        {
            UpdateUIEvent ue = (UpdateUIEvent)e;
            ue.Enabled = m_moveAllow;
        }

        //---------------------------------------------------------------------

        public void OnUpdateUIPasteText(object sender, Event e)
        {
            UpdateUIEvent ue = (UpdateUIEvent)e;
            ue.Enabled = CTheClipboard.TheClipboard.IsSupported(new DataFormat(DataFormatId.wxDF_TEXT));
        }

        //---------------------------------------------------------------------

        public void OnDrag(object sender, Event e)
        {
            string strText = new GetTextFromUser(
                "After you enter text in this dialog, press any mouse\n" +
                "button in the bottom (empty) part of the frame and \n" +
                "drag it anywhere - you will be in fact dragging the\n" +
                "text object containing this text",
                    "Please enter some text", m_strText, this);

            if (strText.Length > 0)
            {
                m_strText = null;
                m_strText = strText;
            }
        }

        //---------------------------------------------------------------------

        public void OnDragMoveByDefault(object sender, Event e)
        {
            CommandEvent ce = (CommandEvent)e;
            m_moveByDefault = ce.IsChecked;
        }

        //---------------------------------------------------------------------

        public void OnDragMoveAllow(object sender, Event e)
        {
            CommandEvent ce = (CommandEvent)e;
            m_moveAllow = ce.IsChecked;
        }

        //---------------------------------------------------------------------

        public void OnHelp(object sender, Event e)
        {
            MessageDialog md = new MessageDialog(this,
                "This small program demonstrates drag & drop support in wx.NET. The program window\n" +
                "consists of 3 parts: the bottom pane is for debug messages, so that you can see what's\n" +
                            "going on inside. The top part is split into 2 listboxes, the left one accepts files\n" +
                            "and the right one accepts text.\n" +
                            "\n" +
                            "To test wxDropTarget: open wordpad (write.exe), select some text in it and drag it to\n" +
                            "the right listbox (you'll notice the usual visual feedback, i.e. the cursor will change).\n" +
                            "Also, try dragging some files (you can select several at once) from Windows Explorer (or \n" +
                            "File Manager) to the left pane. Hold down Ctrl/Shift keys when you drop text (doesn't \n" +
                            "work with files) and see what changes.\n" +
                            "\n" +
                            "To test wxDropSource: just press any mouse button on the empty zone of the window and drag\n" +
                            "it to wordpad or any other droptarget accepting text (and of course you can just drag it\n" +
                            "to the right pane). Due to a lot of trace messages, the cursor might take some time to \n" +
                            "change, don't release the mouse button until it does. You can change the string being\n" +
                            "dragged in in \"File|Test drag...\" dialog.\n",
                            "wxDnD Help");

            md.ShowModal();
        }

        //---------------------------------------------------------------------

        public void OnLogClear(object sender, Event e)
        {
            m_ctrlLog.Clear();
            m_ctrlText.Clear();
            m_ctrlFile.Clear();
        }

        //---------------------------------------------------------------------

        public void OnLeftDown(object sender, Event e)
        {
            if (m_strText.Length > 0)
            {
                TextDataObject textData = new TextDataObject(m_strText);

                if (textData == null)
                {
                    return;
                }

                DropSource source = new DropSource(textData, this);

                Drag flags = Drag.wxDrag_CopyOnly;
                if (m_moveByDefault)
                    flags |= Drag.wxDrag_DefaultMove;
                else if (m_moveAllow)
                    flags |= Drag.wxDrag_AllowMove;

                string result = "";

                switch (source.DoDragDrop(flags))
                {
                    case DragResult.wxDragError: result = "Error!"; break;
                    case DragResult.wxDragNone: result = "Nothing"; break;
                    case DragResult.wxDragCopy: result = "Copied"; break;
                    case DragResult.wxDragMove: result = "Moved"; break;
                    case DragResult.wxDragCancel: result = "Cancelled"; break;
                    default: result = "Huh?"; break;
                }

                StatusText = "Drag result: " + result;
            }
        }

        //---------------------------------------------------------------------

        public void OnRightDown(object sender, Event e)
        {
            MouseEvent me = (MouseEvent)e;

            Menu menu = new Menu("Dnd sample menu");

            menu.Append((int)Cmd.Menu_Drag, "&Test drag");
            menu.AppendSeparator();
            menu.Append((int)Cmd.Menu_About, "&About");

            PopupMenu(menu, me.Position);
        }

        //---------------------------------------------------------------------         

        public void OnCopy(object sender, Event e)
        {
            if (!CTheClipboard.TheClipboard.Open())
            {
                Log.LogError("Can't open clipboard.");
                return;
            }

            if (!CTheClipboard.TheClipboard.AddData(new TextDataObject(m_strText)))
            {
                Log.LogError("Can't copy data to the clipboard");
            }
            else
            {
                Log.LogMessage("Text '{0}' put on the clipboard", m_strText);
            }

            CTheClipboard.TheClipboard.Close();
        }

        //---------------------------------------------------------------------

        public void OnPaste(object sender, Event e)
        {
            if (!CTheClipboard.TheClipboard.Open())
            {
                Log.LogError("Can't open clipboard.");
                return;
            }

            if (!CTheClipboard.TheClipboard.IsSupported(new DataFormat(DataFormatId.wxDF_TEXT)))
            {
                Log.LogWarning("No text data on clipboard");
                CTheClipboard.TheClipboard.Close();
                return;
            }

            TextDataObject text = new TextDataObject();
            if (!CTheClipboard.TheClipboard.GetData(text))
            {
                Log.LogError("Can't paste data from the clipboard");
            }
            else
            {
                Log.LogMessage("Text '{0}' pasted from the clipboard", text.Text);
            }

            CTheClipboard.TheClipboard.Close();
        }
    }

    //---------------------------------------------------------------------     

    public class Dnd : wx.App
    {
        //---------------------------------------------------------------------

        public override bool OnInit()
        {
            DndFrame frame = new DndFrame("Dnd wxWidgets App", new Point(10, 100), new Size(650, 340));
            frame.Show(true);

            return true;
        }

        //---------------------------------------------------------------------

        [STAThread]
        static void Main()
        {
            Dnd app = new Dnd();
            app.Run();
        }

        //---------------------------------------------------------------------
    }
}

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