ActiveItem Property

JavaScript

get_activeItem();
set_activeItem(value);
Object.defineProperty('activeItem');

Property Value

Type	Description
ImageViewerItem	The active item of this image viewer. This value cannot be null.

For more information, refer to Image Viewer Items.

This example will use the viewer as a single-selection enabled list of images and shows how to track the current active item.

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:

JavaScript

// Clear all the images already the viewer
this._imageViewer.items.clear();
// Use vertical view layout
this._imageViewer.viewLayout = new lt.Controls.ImageViewerVerticalViewLayout();
// Make sure the item size is larger than the image size (thumbnails mode)
this._imageViewer.itemSize = lt.LeadSizeD.create(200, 200);
this._imageViewer.imageBorderThickness = 1;
// Change the active item background color
this._imageViewer.activeItemBackgroundColor = "lightblue";
this._imageViewer.selectedItemBackgroundColor = "lightblue";

// Add 4 items to the viewer
for (var page = 1; page <= 4; page++) {
   var item = new lt.Controls.ImageViewerItem();
   var imageUrl = "http://demo.leadtools.com/images/png/ocr" + page.toString() + ".png";
   item.url = imageUrl;
   this._imageViewer.items.add(item);
}

// Add the interface mode to select items (single)
var selectItemsMode = new lt.Controls.ImageViewerSelectItemsInteractiveMode();
selectItemsMode.selectionMode = lt.Controls.ImageViewerSelectionMode.single;
// Tell the mode to set the active item for us
selectItemsMode.autoItemMode = lt.Controls.ImageViewerAutoItemMode.autoSetActive;
this._imageViewer.defaultInteractiveMode = selectItemsMode;

// Hook to the ActiveItemChanged event and update the label
this._imageViewer.activeItemChanged.add(function(sender, e) {
   var index = this.items.indexOf(this.activeItem);
   infoLabel.textContent = "ActiveIndex index is " + index.toString();
});

ActiveItem Property

Property Value

Reference