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ItemImageSize Property

Summary

Gets or sets the maximum size of the image of each RasterImageListItem in the control.

Syntax

C++/CLI

C++

public Size ItemImageSize { get; set; }

public: 
property Size ItemImageSize { 
   Size get(); 
   void set (    Size ); 
}

public:  
   property Size^ ItemImageSize 
   { 
      Size^ get() 
      void set(Size^ value) 
   }

Property Value

A System.Drawing.Size structure that specifies the maximum size of the image of each RasterImageListItem in this RasterImageList in pixels.

Remarks

The ItemImageSize specifies the maximum size of the image of each item in the RasterImageList control. The RasterImageListItem.Image of each image is drawn into the item surface using the maximum size possible of ItemImageSize while maintaining the aspect ratio of the image. If the RasterImageListItem.Image of an item is smaller than ItemImageSize, then no re-sizing is done when the image is drawn. In other words, the RasterImageList control implements a "Fit if larger" drawing algorithm when the item images are painted.

When changing any of the item sizes or styles, you should pay special attention to the values you specify, in general, you should setup ItemSize to be large enough to accommodate ItemImageSize plus room for ItemBorderStyle and ItemImageBorderStyle. If you set the ShowItemText property to true, then you should also accommodate room for the item text in your calculations.

For more information about item appearance, refer to RasterImageList Appearance.

Example

using Leadtools.WinForms; 
using Leadtools; 
using Leadtools.Codecs; 
using Leadtools.Drawing; 
 
class MyForm3 : Form 
{ 
   RasterImageList imageList; 
   RasterCodecs codecs; 
 
   public MyForm3(string title) 
   { 
      Text = title; 
      // Set the size of the form 
      Size = new Size(400, 200); 
 
      // Create a new RasterImageList control 
      imageList = new RasterImageList(); 
      imageList.Dock = DockStyle.Fill; 
      imageList.SelectionMode = RasterImageListSelectionMode.Single; 
      imageList.Size = Size; 
      Controls.Add(imageList); 
      imageList.BringToFront(); 
 
      codecs = new RasterCodecs(); 
 
      // Create three items 
      string imagesPath = LEAD_VARS.ImagesDir; 
 
      for (int i = 0; i < 3; i++) 
      { 
         // Load the image 
         int index = i + 1; 
         string imageFileName = Path.Combine(imagesPath, @"ImageProcessingDemo\Image" + index.ToString() + ".cmp"); 
         RasterImage image = codecs.Load(imageFileName, 0, CodecsLoadByteOrder.BgrOrGray, 1, 1); 
         RasterImageListItem item = new RasterImageListItem(image, 1, "Item" + index.ToString()); 
 
         // Select the first item 
         if (i == 0) 
            item.Selected = true; 
 
         // Add the item to the image list 
         imageList.Items.Add(item); 
      } 
 
      // Change the item size 
      imageList.ItemSize = new Size(200, 200); 
 
      // Change the item image size 
      imageList.ItemImageSize = new Size(120, 120); 
 
      // We are going to draw the items ourselves 
      imageList.ViewStyle = RasterImageListViewStyle.OwnerDraw; 
 
      // Add a handler to the DrawItem event 
      imageList.DrawItem += new EventHandler<RasterImageListDrawItemEventArgs>(rasterImageList_DrawItem); 
 
      // Add the RasterImageList to the control collection. 
      Controls.Add(imageList); 
   } 
 
   private void rasterImageList_DrawItem(object sender, RasterImageListDrawItemEventArgs e) 
   { 
      RasterImageListItem item = e.Item; 
      RasterImageList imageList = item.ImageList; 
      Graphics g = e.Graphics; 
 
      // get the item rectangle 
      Rectangle rc = imageList.GetItemRectangle(item); 
 
      // sanity check 
      if (rc.IsEmpty) 
         return; 
 
      // we want to draw a 1 pixel black rectangle around the item 
      // then we fill the inside of the rectangle with white if the item 
      // is not selected or lightgray if it is 
 
      g.DrawRectangle(Pens.Black, rc.Left, rc.Top, rc.Width - 1, rc.Height - 1); 
 
      // we used up 1 pixel 
      rc.Inflate(-1, -1); 
 
      Brush b; 
      if (item.Selected) 
         b = Brushes.LightGray; 
      else 
         b = Brushes.White; 
      g.FillRectangle(b, rc); 
 
      // calculate the rectangles for image and text 
      if (imageList.ShowItemText) 
      { 
         // text is visible 
         // draw the text at the bottom of the item 
         int textHeight = (int)(g.MeasureString("WWW", imageList.Font).Height + 4); 
         Rectangle textRect = Rectangle.FromLTRB( 
            rc.Left, 
            rc.Bottom - textHeight, 
            rc.Right, 
            rc.Bottom); 
 
         if (!textRect.IsEmpty) 
         { 
            StringFormat sf = new StringFormat(); 
            sf.Alignment = StringAlignment.Center; 
            sf.LineAlignment = StringAlignment.Center; 
            sf.Trimming = StringTrimming.EllipsisPath; 
            sf.FormatFlags = StringFormatFlags.NoWrap; 
 
            g.DrawString( 
               item.Text, 
               imageList.Font, 
               Brushes.Black, 
               textRect, 
               sf); 
            sf.Dispose(); 
 
            // we need to update the item rectangle for the space 
            // we used up to draw the text 
            rc.Height -= textRect.Height; 
         } 
      } 
 
      // rc is the image rectangle 
      if (!rc.IsEmpty) 
      { 
         // now rc holds the rectangle to draw the image into 
 
         // first, set the correct page 
         int savePage = -1; 
         if (item.Image.Page != item.Page) 
         { 
            // the page is different 
 
            // save current image page so we can set it back when we are done 
            savePage = item.Image.Page; 
 
            // disable the image events, we are going to set the page back, 
            // so we do not want anybody subscribing to this image Changed 
            // event to know we changed it. 
            item.Image.DisableEvents(); 
 
            // set new page 
            item.Image.Page = item.Page; 
         } 
 
         try 
         { 
            // we want to center the image into whatever left of rc 
            Size itemImageSize = imageList.ItemImageSize; 
            Rectangle imageRect = new Rectangle( 
               rc.Left + (rc.Width - itemImageSize.Width) / 2, 
               rc.Top + (rc.Height - itemImageSize.Height) / 2, 
               itemImageSize.Width, 
               itemImageSize.Height); 
 
            // we want to keep the aspect ratio 
            imageRect = RasterImageList.GetFixedAspectRatioImageRectangle( 
               item.Image.ImageWidth, 
               item.Image.ImageHeight, 
               imageRect); 
 
            // draw the image 
            LeadRect lRect = new LeadRect(imageRect.Left, imageRect.Top, imageRect.Width, imageRect.Height); 
            RasterImagePainter.Paint(item.Image, e.Graphics, lRect, imageList.PaintProperties); 
 
            // finally, draw a black rectangle around the image 
            imageRect.Inflate(1, 1); 
            g.DrawRectangle( 
               Pens.Black, 
               imageRect.Left, 
               imageRect.Top, 
               imageRect.Width - 1, 
               imageRect.Height - 1); 
         } 
         finally 
         { 
            // reset the old page 
            if (savePage != -1) 
            { 
               item.Image.Page = savePage; 
 
               // re-enable the events 
               item.Image.EnableEvents(); 
            } 
         } 
      } 
   } 
} 
 
public void RasterImageList_DrawItem(string title) 
{ 
   MyForm3 form = new MyForm3(title); 
   form.ShowDialog(); 
} 
 
static class LEAD_VARS 
{ 
   public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; 
}

Requirements

Target Platforms