EnsureItemVisible Method (original) (raw)
Summary
Ensures that an item is visible in the viewer.
Syntax
Parameters
item
The reference item. This parameter cannot be null.
Example
using Leadtools;
using Leadtools.Controls;
using Leadtools.Codecs;
using Leadtools.Drawing;
using Leadtools.ImageProcessing;
using Leadtools.ImageProcessing.Color;
public void ImageViewerGotoItemByIndex_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.ItemPadding = new Padding(8, 8, 8, 20);
_imageViewer.ImageBorderThickness = 1;
// 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);
}
item.Text = string.Format("Item {0}", page - 1);
_imageViewer.Items.Add(item);
}
}
// Add a combobox control to show the items
var comboBox = new ComboBox();
comboBox.Top = _label.Bottom;
if (_label.Parent != null)
{
_label.Parent.Controls.Add(comboBox);
}
// Add an entry for each item to the combo box
foreach (var item in _imageViewer.Items)
comboBox.Items.Add(item.Text);
// When the user selects an item from the combo box ...
comboBox.SelectedIndexChanged += (sender, e) =>
{
// Get the corresponding item index...
var index = comboBox.SelectedIndex;
// And go to it
_imageViewer.GotoItemByIndex(index);
};
}
static class LEAD_VARS
{
public const string ImagesDir = @"C:\LEADTOOLS22\Resources\Images";
}