In System.Windows.Forms:

[mono-project.git] / mcs / class / Managed.Windows.Forms / System.Windows.Forms / Splitter.cs

// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
// 
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
// Copyright (c) 2005-2008 Novell, Inc. (http://www.novell.com)
//
// Authors:
//      Peter Dennis Bartok     (pbartok@novell.com)
//      Ivan N. Zlatev          (contact i-nz.net)
//
//

// COMPLETE

#undef Debug

using System;
using System.ComponentModel;
using System.Drawing;
using System.Reflection;
using System.Runtime.InteropServices;

namespace System.Windows.Forms {
#if NET_2_0
        [ComVisible (true)]
        [ClassInterface (ClassInterfaceType.AutoDispatch)]
#endif
        [DefaultEvent("SplitterMoved")]
        [Designer("System.Windows.Forms.Design.SplitterDesigner, " + Consts.AssemblySystem_Design, "System.ComponentModel.Design.IDesigner")]
        [DefaultProperty("Dock")]
        public class Splitter : Control
#if !NET_2_0
        , IMessageFilter
#endif
        {
                #region Local Variables
                static private Cursor           splitter_ns;
                static private Cursor           splitter_we;
                // XXX this "new" shouldn't be here.  Control shouldn't define border_style as internal.
                new private BorderStyle         border_style;
                private int                     min_extra;
                private int                     min_size;
                private int                     max_size;
                private int                     splitter_size;          // Size (width or height) of our splitter control
                private bool                    horizontal;             // true if we've got a horizontal splitter
                private Control                 affected;               // The control that the splitter resizes
                private int                     split_requested;        // If the user requests a position before we have ever laid out the doc
                private int                     splitter_prev_move;
                private Rectangle               splitter_rectangle_moving;
                #endregion      // Local Variables

                #region Constructors
                static Splitter() {
                        splitter_ns = Cursors.HSplit;
                        splitter_we = Cursors.VSplit;
                }

                public Splitter() {

                        min_extra = 25;
                        min_size = 25;
                        split_requested = -1;
                        splitter_size = 3;
                        horizontal = false;

                        SetStyle(ControlStyles.Selectable, false);
                        Anchor = AnchorStyles.None;
                        Dock = DockStyle.Left;

                        Layout += new LayoutEventHandler(LayoutSplitter);
                        this.ParentChanged += new EventHandler(ReparentSplitter);
                        Cursor = splitter_we;
                }
                #endregion      // Constructors

                #region Public Instance Properties
                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override bool AllowDrop {
                        get {
                                return base.AllowDrop;
                        }

                        set {
                                base.AllowDrop = value;
                        }
                }

                [Browsable(false)]
                [DefaultValue(AnchorStyles.None)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override AnchorStyles Anchor {
                        get {
                                return AnchorStyles.None;
                        }

                        set {
                                ;       // MS doesn't set it
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Image BackgroundImage {
                        get {
                                return base.BackgroundImage;
                        }

                        set {
                                base.BackgroundImage = value;
                        }
                }

#if NET_2_0
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public override ImageLayout BackgroundImageLayout {
                        get { return base.BackgroundImageLayout; }
                        set { base.BackgroundImageLayout = value; }
                }
#endif

                [DispId(-504)]
                [DefaultValue (BorderStyle.None)]
                [MWFDescription("Sets the border style for the splitter")]
                [MWFCategory("Appearance")]
                public BorderStyle BorderStyle {
                        get {
                                return border_style;
                        }

                        set {
                                border_style = value;

                                switch(value) {
                                case BorderStyle.FixedSingle:
                                        splitter_size = 4;      // We don't get motion events for 1px wide windows on X11. sigh.
                                        break;

                                case BorderStyle.Fixed3D:
                                        value = BorderStyle.None;
                                        splitter_size = 3;
                                        break;

                                case BorderStyle.None:
                                        splitter_size = 3;
                                        break;

                                default:
                                        throw new InvalidEnumArgumentException (string.Format("Enum argument value '{0}' is not valid for BorderStyle", value));
                                }

                                base.InternalBorderStyle = value;
                        }
                }

                [DefaultValue(DockStyle.Left)]
                [Localizable(true)]
                public override DockStyle Dock {
                        get {
                                return base.Dock;
                        }

                        set {
                                if (!Enum.IsDefined (typeof (DockStyle), value) || (value == DockStyle.None) || (value == DockStyle.Fill)) {
                                        throw new ArgumentException("Splitter must be docked left, top, bottom or right");
                                }

                                if ((value == DockStyle.Top) || (value == DockStyle.Bottom)) {
                                        horizontal = true;
                                        Cursor = splitter_ns;
                                } else {
                                        horizontal = false;
                                        Cursor = splitter_we;
                                }
                                base.Dock = value;
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Font Font {
                        get {
                                return base.Font;
                        }

                        set {
                                base.Font = value;
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override Color ForeColor {
                        get {
                                return base.ForeColor;
                        }

                        set {
                                base.ForeColor = value;
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new ImeMode ImeMode {
                        get {
                                return base.ImeMode;
                        }

                        set {
                                base.ImeMode = value;
                        }
                }

                [DefaultValue(25)]
                [Localizable(true)]
                [MWFDescription("Sets minimum size of undocked window")]
                [MWFCategory("Behaviour")]
                public int MinExtra {
                        get {
                                return min_extra;
                        }

                        set {
                                min_extra = value;
                        }
                }

                [DefaultValue(25)]
                [Localizable(true)]
                [MWFDescription("Sets minimum size of the resized control")]
                [MWFCategory("Behaviour")]
                public int MinSize {
                        get {
                                return min_size;
                        }

                        set {
                                min_size = value;
                        }
                }

                private int MaxSize {
                        get {
                                if (this.Parent == null)
                                        return 0;

                                if (affected == null)
                                        affected = AffectedControl;

                                int widths = 0;
                                int heights = 0;
                                foreach (Control c in this.Parent.Controls) {
                                        if (c != affected) {
                                                switch (c.Dock) {
                                                case DockStyle.Left:
                                                case DockStyle.Right:
                                                        widths += c.Width;
                                                        break;
                                                case DockStyle.Top:
                                                case DockStyle.Bottom:
                                                        heights += c.Height;
                                                        break;
                                                }
                                        }
                                }

                                if (horizontal)
                                        return Parent.ClientSize.Height - heights - MinExtra;
                                else
                                        return Parent.ClientSize.Width - widths - MinExtra;
                        }
                }
                
                [Browsable(false)]
                [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
                [MWFDescription("Current splitter position")]
                [MWFCategory("Layout")]
                public int SplitPosition {
                        get {
                                affected = AffectedControl;
                                if (affected == null) {
                                        return -1;
                                }

                                if (Capture) {
                                        return CalculateSplitPosition();
                                }

                                if (horizontal) {
                                        return affected.Height;
                                } else {
                                        return affected.Width;
                                }
                        }

                        set {
                                if (value > MaxSize)
                                        value = MaxSize;
                                if (value < MinSize)
                                        value = MinSize;

                                affected = AffectedControl;
                                if (affected == null)
                                        split_requested = value;
                                else {
                                        if (horizontal)
                                                affected.Height = value;
                                        else
                                                affected.Width = value;
                                        OnSplitterMoved (new SplitterEventArgs (Left, Top, value, value));
                                }
                        }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new bool TabStop {
                        get { return base.TabStop; }
                        set { base.TabStop = value; }
                }

                [Bindable(false)]
                [Browsable(false)]
                [DesignerSerializationVisibility(DesignerSerializationVisibility.Hidden)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public override string Text {
                        get {
                                return base.Text;
                        }

                        set {
                                base.Text = value;
                        }
                }

                #endregion      // Public Instance Properties

                #region Protected Instance Properties
                protected override CreateParams CreateParams {
                        get {
                                return base.CreateParams;
                        }
                }

#if NET_2_0
                protected override Cursor DefaultCursor {
                        get { return base.DefaultCursor; }
                }
#endif

                protected override ImeMode DefaultImeMode {
                        get {
                                return ImeMode.Disable;
                        }
                }

                protected override Size DefaultSize {
                        get {
                                return new Size (3, 3);
                        }
                }
                #endregion      // Protected Instance Properties

                #region Public Instance Methods
#if !NET_2_0
                public bool PreFilterMessage(ref Message m) {
                        return false;
                }
#endif

                public override string ToString() {
                        return base.ToString () + String.Format(", MinExtra: {0}, MinSize: {1}", min_extra, min_size);
                }
                #endregion      // Public Instance Methods

                #region Protected Instance Methods
                protected override void OnKeyDown(KeyEventArgs e) {
                        base.OnKeyDown (e);
                        if (Capture && (e.KeyCode == Keys.Escape)) {
                                Capture = false;
                                SplitterEndMove (Point.Empty, true);
                        }
                }

                protected override void OnMouseDown(MouseEventArgs e) {
                        base.OnMouseDown (e);

                        // Only allow if we are set up properly
                        if (affected == null)
                                affected = AffectedControl;
                        max_size = MaxSize;

                        if (affected == null || e.Button != MouseButtons.Left)
                                return;

                        Capture = true;
                        SplitterBeginMove (Parent.PointToClient (PointToScreen (new Point (e.X, e.Y))));
                }

                protected override void OnMouseMove(MouseEventArgs e) {
                        base.OnMouseMove (e);

                        if (!Capture  || e.Button != MouseButtons.Left || affected == null)
                                return;

                        // We need our mouse coordinates relative to our parent
                        SplitterMove (Parent.PointToClient (PointToScreen (new Point (e.X, e.Y))));
                }

                protected override void OnMouseUp(MouseEventArgs e) {
                        if (!Capture || e.Button != MouseButtons.Left || affected == null) {
                                base.OnMouseUp (e);
                                return;
                        }

                        base.OnMouseUp (e);
                        Capture = false;
                        SplitterEndMove (Parent.PointToClient (PointToScreen (new Point (e.X, e.Y))), false);
                }

                private void SplitterBeginMove (Point location)
                {
                        splitter_rectangle_moving = new Rectangle (Bounds.X, Bounds.Y,
                                                                   Width, Height);
                        splitter_prev_move = horizontal ? location.Y : location.X;
                }

                private void SplitterMove (Point location)
                {
                        int currentMove = horizontal ? location.Y : location.X;
                        int delta = currentMove - splitter_prev_move;
                        Rectangle prev_location = splitter_rectangle_moving;
                        bool moved = false;
                        int min = this.MinSize;
                        int max = max_size;

                        if (horizontal) {
                                if (splitter_rectangle_moving.Y + delta > min && splitter_rectangle_moving.Y + delta < max) {
                                        splitter_rectangle_moving.Y += delta;
                                        moved = true;
                                } else {
                                        // Ensure that the splitter is set to minimum or maximum position, 
                                        // even if the mouse "skips".
                                        //
                                        if (splitter_rectangle_moving.Y + delta <= min && splitter_rectangle_moving.Y != min) {
                                                splitter_rectangle_moving.Y = min;
                                                moved = true;
                                        } else if (splitter_rectangle_moving.Y + delta >= max && splitter_rectangle_moving.Y != max) {
                                                splitter_rectangle_moving.Y = max;
                                                moved = true;
                                        }
                                }
                        } else {
                                if (splitter_rectangle_moving.X + delta > min && splitter_rectangle_moving.X + delta < max) {
                                        splitter_rectangle_moving.X += delta;
                                        moved = true;
                                } else {
                                        // Ensure that the splitter is set to minimum or maximum position, 
                                        // even if the mouse "skips".
                                        //
                                        if (splitter_rectangle_moving.X + delta <= min && splitter_rectangle_moving.X != min) {
                                                splitter_rectangle_moving.X = min;
                                                moved = true;
                                        } else if (splitter_rectangle_moving.X + delta >= max && splitter_rectangle_moving.X != max) {
                                                splitter_rectangle_moving.X = max;
                                                moved = true;
                                        }
                                }
                        }

                        if (moved) {
                                splitter_prev_move = currentMove;
                                OnSplitterMoving (new SplitterEventArgs (location.X, location.Y, 
                                                                         splitter_rectangle_moving.X, 
                                                                         splitter_rectangle_moving.Y));
                                XplatUI.DrawReversibleRectangle (this.Parent.Handle, prev_location, 1);
                                XplatUI.DrawReversibleRectangle (this.Parent.Handle, splitter_rectangle_moving, 1);
                        }
                }

                private void SplitterEndMove (Point location, bool cancel)
                {
                        if (!cancel) {
                                // Resize the affected window
                                if (horizontal)
                                        affected.Height = CalculateSplitPosition();
                                else
                                        affected.Width = CalculateSplitPosition();
                        }

                        this.Parent.Refresh (); // to clean up the drag handle artifacts from all controls
                        SplitterEventArgs args = new SplitterEventArgs (location.X, location.Y, 
                                                                        splitter_rectangle_moving.X, 
                                                                        splitter_rectangle_moving.Y);
                        OnSplitterMoved (args);
                }

                protected virtual void OnSplitterMoved(SplitterEventArgs sevent) {
                        SplitterEventHandler eh = (SplitterEventHandler)(Events [SplitterMovedEvent]);
                        if (eh != null)
                                eh (this, sevent);
                }

                protected virtual void OnSplitterMoving(SplitterEventArgs sevent) {
                        SplitterEventHandler eh = (SplitterEventHandler)(Events [SplitterMovingEvent]);
                        if (eh != null)
                                eh (this, sevent);
                }

                protected override void SetBoundsCore(int x, int y, int width, int height, BoundsSpecified specified) {
                        // enforce our width / height
                        if (horizontal) {
                                splitter_size = height;
                                if (splitter_size < 1) {
                                        splitter_size = 3;
                                }
                                base.SetBoundsCore (x, y, width, splitter_size, specified);
                        } else {
                                splitter_size = width;
                                if (splitter_size < 1) {
                                        splitter_size = 3;
                                }
                                base.SetBoundsCore (x, y, splitter_size, height, specified);
                        }
                }
                #endregion      // Protected Instance Methods

                #region Private Properties and Methods
                private Control AffectedControl {
                        get {
                                if (Parent == null)
                                        return null;

                                // Doc says the first control preceeding us in the zorder 
                                for (int i = Parent.Controls.GetChildIndex(this) + 1; i < Parent.Controls.Count; i++) {
                                        switch (Dock) {
                                        case DockStyle.Top:
                                                if (Top == Parent.Controls[i].Bottom)
                                                        return Parent.Controls[i];
                                                break;
                                        case DockStyle.Bottom:
                                                if (Bottom == Parent.Controls[i].Top)
                                                        return Parent.Controls[i];
                                                break;
                                        case DockStyle.Left:
                                                if (Left == Parent.Controls[i].Right)
                                                        return Parent.Controls[i];
                                                break;
                                        case DockStyle.Right:
                                                if (Right == Parent.Controls[i].Left)
                                                        return Parent.Controls[i];
                                                break;
                                        }
                                }
                                return null;
                        }
                }

                private int CalculateSplitPosition() {
                        if (horizontal) {
                                if (Dock == DockStyle.Top)
                                        return splitter_rectangle_moving.Y - affected.Top;
                                else
                                        return affected.Bottom - splitter_rectangle_moving.Y - splitter_size;
                        } else {
                                if (Dock == DockStyle.Left)
                                        return splitter_rectangle_moving.X - affected.Left;
                                else
                                        return affected.Right - splitter_rectangle_moving.X - splitter_size;
                        }
                }

                internal override void OnPaintInternal (PaintEventArgs e) {
                        e.Graphics.FillRectangle(ThemeEngine.Current.ResPool.GetSolidBrush(this.BackColor), e.ClipRectangle);
                }

                private void LayoutSplitter(object sender, LayoutEventArgs e) {
                        affected = AffectedControl;
                        if (split_requested != -1) {
                                SplitPosition = split_requested;
                                split_requested = -1;
                        }
                }

                private void ReparentSplitter(object sender, EventArgs e) {
                        affected = null;
                }

                #endregion      // Private Properties and Methods

                #region Events
                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler BackgroundImageChanged {
                        add { base.BackgroundImageChanged += value; }
                        remove { base.BackgroundImageChanged -= value; }
                }

#if NET_2_0
                [Browsable (false)]
                [EditorBrowsable (EditorBrowsableState.Never)]
                public new event EventHandler BackgroundImageLayoutChanged
                {
                        add { base.BackgroundImageLayoutChanged += value; }
                        remove { base.BackgroundImageLayoutChanged -= value; }
                }
                
#endif

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler Enter {
                        add { base.Enter += value; }
                        remove { base.Enter -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler FontChanged {
                        add { base.FontChanged += value; }
                        remove { base.FontChanged -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler ForeColorChanged {
                        add { base.ForeColorChanged += value; }
                        remove { base.ForeColorChanged -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler ImeModeChanged {
                        add { base.ImeModeChanged += value; }
                        remove { base.ImeModeChanged -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event KeyEventHandler KeyDown {
                        add { base.KeyDown += value; }
                        remove { base.KeyDown -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event KeyPressEventHandler KeyPress {
                        add { base.KeyPress += value; }
                        remove { base.KeyPress -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event KeyEventHandler KeyUp {
                        add { base.KeyUp += value; }
                        remove { base.KeyUp -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler Leave {
                        add { base.Leave += value; }
                        remove { base.Leave -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler TabStopChanged {
                        add { base.TabStopChanged += value; }
                        remove { base.TabStopChanged -= value; }
                }

                [Browsable(false)]
                [EditorBrowsable(EditorBrowsableState.Never)]
                public new event EventHandler TextChanged {
                        add { base.TextChanged += value; }
                        remove { base.TextChanged -= value; }
                }

                static object SplitterMovedEvent = new object ();
                static object SplitterMovingEvent = new object ();

                public event SplitterEventHandler SplitterMoved {
                        add { Events.AddHandler (SplitterMovedEvent, value); }
                        remove { Events.RemoveHandler (SplitterMovedEvent, value); }
                }

                public event SplitterEventHandler SplitterMoving {
                        add { Events.AddHandler (SplitterMovingEvent, value); }
                        remove { Events.RemoveHandler (SplitterMovingEvent, value); }
                }
                #endregion      // Events
        }
}