ImageViewerViewLayout Class

Summary

Defines an ImageViewer layout controller.

Syntax

C++/CLI

public abstract class ImageViewerViewLayout

public ref class ImageViewerViewLayout abstract

Remarks

ImageViewerViewLayout is the main class responsible for setting up the image viewer layout.

Derived classes must implement the following:

Name: Return the friendly name of the layout.
UpdateTransform: Called by ImageViewer.UpdateTransform to move and size the items in the layout.

The layout must perform the following actions when UpdateTransform is called. All the values calculation must use the scale factor passed to the method and the viewer will update for view alignment after the method returns:

Update the itemBounds property: This is an array of rectangles that must be filled with the location and size of each item. Each value must be calculated based on the item size and its transformations. The items must be arranged in any way desired usually creating rows and columns or stacked on top of each other.
Update the values of ImageViewerItem.RowIndex and ImageViewerItem.ColumnIndex for each item: These values must be set to the 0-based index of the item row and column in the view grid (if any). The value will be used by code that requires finding the item to the left, top, right or bottom of another item such as ImageViewerSelectItemsInteractiveMode when using the arrow keys.
Set the value of SizeModeWidth: This is the width of the layout in pixels. The viewer will use this value to control how much to zoom when FitWidth> is used for example. Typically this should be the width of largest column.
Set the value of SizeModeWidthItemCount: The number of items in the largest column.
Set the value of SizeModeHeight: This is the height of the layout in pixels. The viewer will use this value to control how much to zoom when FitHeight is used for example. Typically this should be the height of the largest row.
Set the value of SizeModeHeightItemCount: The number of items in the largest row.

The following methods are available to help with the calculations of these values:

AlignHeights: Align the heights of the items and return the largest value.
AlignWidths: Align the widths of the items and return the largest value.
AlignRow: Align the items to even distances in a row.
AlignColumn: Align the items to even distances in a column.

For more information, refer to Image Viewer Layouts, Image Viewer Items, Image Viewer Transformation and Image Viewer Bounds and Transform.

Example

using Leadtools; 
using Leadtools.Controls; 
using Leadtools.Codecs; 
using Leadtools.Drawing; 
using Leadtools.ImageProcessing; 
using Leadtools.ImageProcessing.Color; 
 
 
public void ImageViewerViewLayout_Example() 
{ 
   ImageViewerViewLayout layout = new ImageViewerHorizontalViewLayout { Rows = 2 }; 
   _imageViewer.ViewLayout = layout; 
   _imageViewer.UpdateTransform(); 
   _imageViewer.Invalidate(); 
 
   string msg = string.Format("Layout.Name = {0}\nLayout.SizeModeHeight = {1}\nLayout.SizeModeHeightItemCount = {2}\nLayout.SizeModeWidth = {3}\nLayout.SizeModeWidthItemCount = {4}\n", 
      _imageViewer.ViewLayout.Name, 
      _imageViewer.ViewLayout.SizeModeHeight, 
      _imageViewer.ViewLayout.SizeModeHeightItemCount, 
      _imageViewer.ViewLayout.SizeModeWidth, 
      _imageViewer.ViewLayout.SizeModeWidthItemCount); 
   Debug.WriteLine(msg, "ImageViewerLayout Information"); 
}

Requirements

Target Platforms

Reference

ImageViewerViewLayout Members

Leadtools.Controls Namespace

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