CheckBoxBaseAdapter.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / FX-1434 / FX-1434 / 1.0 / untmp / whidbey / REDBITS / ndp / fx / src / WinForms / Managed / System / WinForms / ButtonInternal / CheckBoxBaseAdapter.cs / 1 / CheckBoxBaseAdapter.cs
                        

                        
                            //------------------------------------------------------------------------------ 
// 
//     Copyright (c) Microsoft Corporation.  All rights reserved.
// 
//----------------------------------------------------------------------------- 

namespace System.Windows.Forms.ButtonInternal { 
    using System; 
    using System.Diagnostics;
    using System.Drawing; 
    using System.Windows.Forms.Internal;
    using System.Drawing.Drawing2D;
    using System.Drawing.Imaging;
    using System.Drawing.Text; 
    using System.Windows.Forms;
    using System.Windows.Forms.VisualStyles; 
    using System.Runtime.InteropServices; 

    internal abstract class CheckBoxBaseAdapter : CheckableControlBaseAdapter { 

        protected const int flatCheckSize = 11;

        [ThreadStatic] 
        private static Bitmap checkImageChecked = null;
        [ThreadStatic] 
        private static Color checkImageCheckedBackColor         = Color.Empty; 

        [ThreadStatic] 
        private static Bitmap checkImageIndeterminate    = null;
        [ThreadStatic]
        private static Color checkImageIndeterminateBackColor   = Color.Empty;
 
        internal CheckBoxBaseAdapter(ButtonBase control) : base(control) {}
 
        protected new CheckBox Control { 
            get {
                return ((CheckBox)base.Control); 
            }
        }

        #region Drawing Helpers 

        protected void DrawCheckFlat(PaintEventArgs e, LayoutData layout, Color checkColor, Color checkBackground, Color checkBorder, ColorData colors) { 
            Rectangle bounds = layout.checkBounds; 
            // Removed subtracting one for Width and Height. In Everett we needed to do this,
            // since we were using GDI+ to draw the border. Now that we are using GDI, 
            // we should not do before drawing the border.

            if (!layout.options.everettButtonCompat) {
                bounds.Width--; 
                bounds.Height--;
            } 
            using (WindowsGraphics wg = WindowsGraphics.FromGraphics( e.Graphics )) { 
                using(WindowsPen pen = new WindowsPen(wg.DeviceContext, checkBorder)){
                    wg.DrawRectangle(pen, bounds); 
                }

                // Now subtract, since the rest of the code is like Everett.
                if (layout.options.everettButtonCompat) { 
                    bounds.Width--;
                    bounds.Height--; 
                } 
                bounds.Inflate(-1, -1);
            } 
            if (Control.CheckState == CheckState.Indeterminate) {
                bounds.Width++;
                bounds.Height++;
                DrawDitheredFill(e.Graphics, colors.buttonFace, checkBackground, bounds); 
            }
            else { 
                using( WindowsGraphics wg = WindowsGraphics.FromGraphics( e.Graphics )) { 
                    using (WindowsBrush brush = new WindowsSolidBrush(wg.DeviceContext, checkBackground)) {
                        // Even though we are using GDI here as opposed to GDI+ in Everett, we still need to add 1. 
                        bounds.Width++;
                        bounds.Height++;
                        wg.FillRectangle(brush, bounds);
                    } 
                }
            } 
            DrawCheckOnly(e, layout, colors, checkColor, checkBackground, true); 

        } 

        // used by DataGridViewCheckBoxCell
        internal static void DrawCheckBackground(bool controlEnabled, CheckState controlCheckState, Graphics g, Rectangle bounds, Color checkColor, Color checkBackground, bool disabledColors, ColorData colors)
        { 
            using ( WindowsGraphics wg = WindowsGraphics.FromGraphics( g )) {
                WindowsBrush brush; 
                if (!controlEnabled && disabledColors) { 
                    brush = new WindowsSolidBrush(wg.DeviceContext, SystemColors.Control);
                } 
                else if (controlCheckState == CheckState.Indeterminate && checkBackground == SystemColors.Window && disabledColors) {
                    Color comboColor = SystemInformation.HighContrast ? SystemColors.ControlDark :
                            SystemColors.Control;
                    byte R = (byte)((comboColor.R + SystemColors.Window.R) / 2); 
                    byte G = (byte)((comboColor.G + SystemColors.Window.G) / 2);
                    byte B = (byte)((comboColor.B + SystemColors.Window.B) / 2); 
                    brush = new WindowsSolidBrush(wg.DeviceContext, Color.FromArgb(R, G, B)); 
                }
                else { 
                    brush = new WindowsSolidBrush(wg.DeviceContext, checkBackground);
                }

                try { 
                    wg.FillRectangle(brush, bounds);
                } 
                finally { 
                    if (brush != null) {
                        brush.Dispose(); 
                    }
                }
            }
        } 

        protected void DrawCheckBackground(PaintEventArgs e, Rectangle bounds, Color checkColor, Color checkBackground, bool disabledColors, ColorData colors) { 
            // area behind check 
            //
            if (Control.CheckState == CheckState.Indeterminate) { 
                DrawDitheredFill(e.Graphics, colors.buttonFace, checkBackground, bounds);
            }
            else {
                DrawCheckBackground(Control.Enabled, Control.CheckState, e.Graphics, bounds, checkColor, checkBackground, disabledColors, colors); 
            }
        } 
 
        protected void DrawCheckOnly(PaintEventArgs e, LayoutData layout, ColorData colors, Color checkColor, Color checkBackground, bool disabledColors) {
            DrawCheckOnly(flatCheckSize, Control.Checked, Control.Enabled, Control.CheckState, e.Graphics, layout, colors, checkColor, checkBackground, disabledColors); 
        }

        // used by DataGridViewCheckBoxCell
        internal static void DrawCheckOnly(int checkSize, bool controlChecked, bool controlEnabled, CheckState controlCheckState, Graphics g, LayoutData layout, ColorData colors, Color checkColor, Color checkBackground, bool disabledColors) { 

            // check 
            // 
            if (controlChecked) {
                if (!controlEnabled && disabledColors) { 
                    checkColor = colors.buttonShadow;
                }
                else if (controlCheckState == CheckState.Indeterminate && disabledColors) {
                    checkColor = SystemInformation.HighContrast ? colors.highlight : 
                       colors.buttonShadow;
                } 
 
                Rectangle fullSize = layout.checkBounds;
 
                if (fullSize.Width == checkSize) {
                    fullSize.Width++;
                    fullSize.Height++;
                } 

                fullSize.Width++; 
                fullSize.Height++; 
                Bitmap checkImage = null;
                if (controlCheckState == CheckState.Checked) { 
                    checkImage = GetCheckBoxImage(checkColor, fullSize, ref checkImageCheckedBackColor, ref checkImageChecked);
                } else {
                    Debug.Assert(controlCheckState == CheckState.Indeterminate, "we want to paint the check box only if the item is checked or indeterminate");
                    checkImage = GetCheckBoxImage(checkColor, fullSize, ref checkImageIndeterminateBackColor, ref checkImageIndeterminate); 
                }
 
                if (layout.options.everettButtonCompat) { 
                    fullSize.Y -= 1;
                } 
                else {
                    fullSize.Y -= 2;
                }
 
                ControlPaint.DrawImageColorized(g, checkImage, fullSize, checkColor);
            } 
        } 

        internal static Rectangle DrawPopupBorder(Graphics g, Rectangle r, ColorData colors) { 
            using (WindowsGraphics wg = WindowsGraphics.FromGraphics( g )) {

                using( WindowsPen high = new WindowsPen(wg.DeviceContext, colors.highlight),
                   shadow = new WindowsPen(wg.DeviceContext, colors.buttonShadow), 
                   face = new WindowsPen(wg.DeviceContext, colors.buttonFace)) {
 
                    wg.DrawLine(high, r.Right-1 , r.Top, r.Right-1, r.Bottom); 
                    wg.DrawLine(high, r.Left, r.Bottom-1, r.Right, r.Bottom-1);
 
                    wg.DrawLine(shadow, r.Left, r.Top, r.Left , r.Bottom);
                    wg.DrawLine(shadow, r.Left, r.Top, r.Right- 1, r.Top);

                    wg.DrawLine(face, r.Right - 2, r.Top + 1, r.Right - 2, r.Bottom - 1); 
                    wg.DrawLine(face, r.Left + 1, r.Bottom - 2, r.Right - 1, r.Bottom - 2);
                } 
            } 
            r.Inflate(-1, -1);
            return r; 
        }

        protected ButtonState GetState() {
            ButtonState style = (ButtonState)0; 

            if (Control.CheckState == CheckState.Unchecked) { 
                style |= ButtonState.Normal; 
            }
            else { 
                style |= ButtonState.Checked;
            }

            if (!Control.Enabled) { 
                style |= ButtonState.Inactive;
            } 
 
            if (Control.MouseIsDown) {
                style |= ButtonState.Pushed; 
            }

            return style;
        } 

        protected void DrawCheckBox(PaintEventArgs e, LayoutData layout) { 
            Graphics g = e.Graphics; 

            ButtonState style = GetState(); 

            if (Control.CheckState == CheckState.Indeterminate) {
                if (Application.RenderWithVisualStyles) {
                    CheckBoxRenderer.DrawCheckBox(g, new Point(layout.checkBounds.Left, layout.checkBounds.Top), CheckBoxRenderer.ConvertFromButtonState(style, true, Control.MouseIsOver)); 
                }
                else { 
                    ControlPaint.DrawMixedCheckBox(g, layout.checkBounds, style); 
                }
            } 
            else {
                if (Application.RenderWithVisualStyles) {
                    CheckBoxRenderer.DrawCheckBox(g, new Point(layout.checkBounds.Left, layout.checkBounds.Top), CheckBoxRenderer.ConvertFromButtonState(style, false, Control.MouseIsOver));
                } 
                else {
                    ControlPaint.DrawCheckBox(g, layout.checkBounds, style); 
                } 
            }
        } 

        #endregion

        private static Bitmap GetCheckBoxImage(Color checkColor, Rectangle fullSize, ref Color cacheCheckColor, ref Bitmap cacheCheckImage) 
        {
            if (cacheCheckImage != null && 
                cacheCheckColor.Equals(checkColor) && 
                cacheCheckImage.Width == fullSize.Width &&
                cacheCheckImage.Height == fullSize.Height) { 
                return cacheCheckImage;
            }

            if (cacheCheckImage != null) 
            {
                cacheCheckImage.Dispose(); 
                cacheCheckImage = null; 
            }
 
            // We draw the checkmark slightly off center to eliminate 3-D border artifacts,
            // and compensate below
            NativeMethods.RECT rcCheck = NativeMethods.RECT.FromXYWH(0, 0, fullSize.Width, fullSize.Height);
            Bitmap bitmap = new Bitmap(fullSize.Width, fullSize.Height); 
            Graphics offscreen = Graphics.FromImage(bitmap);
            offscreen.Clear(Color.Transparent); 
            IntPtr dc = offscreen.GetHdc(); 
            try {
                SafeNativeMethods.DrawFrameControl(new HandleRef(offscreen, dc), ref rcCheck, 
                                         NativeMethods.DFC_MENU, NativeMethods.DFCS_MENUCHECK);
            } finally {
                offscreen.ReleaseHdcInternal(dc);
                offscreen.Dispose(); 
            }
 
            bitmap.MakeTransparent(); 
            cacheCheckImage = bitmap;
            cacheCheckColor = checkColor; 

            return cacheCheckImage;
        }
 
        internal override LayoutOptions CommonLayout() {
            LayoutOptions layout = base.CommonLayout(); 
            layout.checkAlign        = Control.CheckAlign; 
            layout.textOffset        = false;
            layout.shadowedText      = !Control.Enabled; 
            layout.layoutRTL         = RightToLeft.Yes == Control.RightToLeft;

            return layout;
        } 
    }
} 

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.
// Copyright (c) Microsoft Corporation. All rights reserved.

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