SelectedItemsChanged Event (original) (raw)

Summary

Occurs when any of the items inside this viewer selection state changes.

Syntax

public event EventHandler SelectedItemsChanged 

public: event EventHandler^ SelectedItemsChanged

Example

This example will use the viewer as a multi-selection enabled list of images and shows how to track the current selected items.

Start with the ImageViewer example, remove all the code inside the example function (search for the "// TODO: add example code here" comment) and insert the following code:

using Leadtools; using Leadtools.Controls; using Leadtools.Codecs; using Leadtools.Drawing; using Leadtools.ImageProcessing; using Leadtools.ImageProcessing.Color; public void SelectedItemsChanged_Example() { // Clear all the images already the viewer _imageViewer.Items.Clear(); // Use vertical view layout _imageViewer.ViewLayout = new ImageViewerVerticalViewLayout(); // Make sure the item size is larger than the image size (thumbnails mode) _imageViewer.ItemSize = LeadSize.Create(200, 200); _imageViewer.ImageBorderThickness = 1; // Change the selected item background color _imageViewer.SelectedItemBackgroundColor = Color.LightBlue; // Add 4 items to the viewer using (var codecs = new RasterCodecs()) { for (var page = 1; page <= 4; page++) { var item = new ImageViewerItem(); var fileName = Path.Combine(LEAD_VARS.ImagesDir, string.Format("ocr{0}.tif", page)); // Create a thumbnail from the image using (var image = codecs.Load(fileName, page)) { item.Image = image.CreateThumbnail(180, 180, 24, RasterViewPerspective.TopLeft, RasterSizeFlags.Resample); } _imageViewer.Items.Add(item); } } // Add the interface mode to select items (multiple) var selectItemsMode = new ImageViewerSelectItemsInteractiveMode(); selectItemsMode.SelectionMode = ImageViewerSelectionMode.Multi; _imageViewer.DefaultInteractiveMode = selectItemsMode; // Hook to the SelectItemsChanged event and update the label _imageViewer.SelectedItemsChanged += (sender, e) => { var sb = new StringBuilder(); sb.Append("Selected indices:"); // Get the selected items var items = _imageViewer.Items.GetSelected(); foreach (var item in items) sb.Append(_imageViewer.Items.IndexOf(item) + " "); _label.Text = sb.ToString(); }; } static class LEAD_VARS { public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images"; }

Event Data