The application controls the appearance of thumbnails in the display using properties in ThumbnailXpress™.
ThumbnailXpress Control Window Appearance
The appearance of the ThumbnailXpress control window is controlled as follows:
- The background color for the control (BackColor)
- The foreground color for the control (ForeColor)
- The style of the border of the control (BorderStyle)
- The margins of the control (BottomMargin, TopMargin, RightMargin, LeftMargin)
- Whether the scrollbar is visible (ShowScrollbar)
- The scrollbar direction (ScrollDirection)
Thumbnail Cell Appearance
The appearance of each individual thumbnail is defined using the "Cell" properties. The following can be specified:
- The thumbnail border color and width (CellBorderColor, CellBorderWidth)
- The dimensions of each thumbnail (CellHeight, CellWidth)
- The spacing between each thumbnail (CellHorizontalSpacing, CellVerticalSpacing)
- The color of the fill between thumbnails (CellSpacingColor)
- The background color of selected thumbnails (SelectBackColor)
- Whether a placeholder image is drawn while waiting for the thumbnail to be generated (ShowImagePlaceholders)
Thumbnail Descriptor Appearance
The appearance of each thumbnail's descriptor is specified using the "Descriptor" properties:
- The alignment of the descriptor (DescriptorHorizontalAlignment, DescriptorVerticalAlignment)
- The background color of the text in the descriptor (TextBackColor)
- The font used for the text (Font)
- The format of the descriptor (DescriptorDisplayMethod)
Set Icon Display Behavior
ThumbnailXpress provides the application with the option to display a pre-image generation "placeholder" icon while the image is being loaded and the thumbnail generated. When ShowImagePlaceholders is set to true, a placeholder image is drawn while waiting for the thumbnail to be generated and a cancel icon is displayed if the generation is cancelled.
- The thumbnail image is being generated. Once generated, this icon is replaced with the thumbnail image.
- The thumbnail image loading was cancelled.
The application can also specify the desired action to take when an error occurs during image loading or thumbnail generation. ThumbnailXpress can either display an error icon to indicate that the thumbnail did not load, or simply abort the loading process without displaying any icon in the control window. When ErrorAction is set to UseErrorIcon, the following icons are displayed, depending on the error encountered:
- The thumbnail image was not loaded, due to an error.
- The thumbnail image was not loaded, because the required software is not licensed by the application.
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If the image file type is not supported by ThumbnailXpress, then the icon that is associated with the file in Windows Explorer will be displayed. |
