README

AwImageGrid

License

This project is licensed under the MIT License - see the LICENSE file for details.

Introduction

See: https://stackoverflow.com/a/8954813/757830

For the fun of it, I wrote an ImageGrid component for Jerry Dodge, user of and asker on Stack Overflow.

It has only a vertical scroll bar; resizing the width of the control adjusts the column count and row count. The images are cached as resized bitmaps in an internal list, along with their file names.

Because loading and resampling these images may take some time, depending on image count, resolution and whether you want to use the Graphics32 library for better resample quality, the component delegates the loading process to a separate thread, which (re)runs on setting the column width or the row height, and on changing the file names or the folder path in which the component tries to find all images of types to be supplied in the FileFormats property.

Features

• Creates and resizes image thumbs in a background thread, from file names with the GDI+ library or from manually added images with the Graphics 32 library
• Automatically recognizes all registered image file formats
• Animated scrolling
• Touchscreen support for scrolling by dragging the grid
• Keyboard support for selecting thumbs
• OwnerDraw support, e.g. for adding captions to the thumbs
• Virtual support for bypassing the automatic creation of thumbs

Properties and events

• ColCount: number of columns, readonly
• Count: number of images, readonly
• Images: list of all manually added images where the thumbs are internally created from
• Items: list of all filename-thumbnail or image-thumbnail combinations
• RowCount: number of rows, readonly
• Thumbs: list of all internally created thumbs
• AutoHideScrollBar: hides the scroll bar when all rows are visible
• BorderStyle: shows or hides themed border
• BorderWidth: margin of the component, outside of the scroll bar
• CellAlignment: alignes thumbs at the left, center or right of the cell
• CellHeight: height of cell
• CellLayout: alignes thumbs at the top, middle or bottom of the cell
• CellSpacing: spacing between the cells
• CellWidth: width of cell
• Color: background color of border and cell spacing
• ColWidth: width of column (equals width of cell plus cell spacing)
• DefaultDrawing: draws all thumbs by default
• DesignPreview: shows thumbs in the designer
• DragScroll: supports scrolling the grid by draging the grid
• FileFormats: image file name extensions by which the file names are filtered
• FileNames: list holding all file names
• Folder: the directory in which the component tries to find all images files
• ItemIndex: selected cell index
• MarkerColor: color of temporarily thumb marker during loading process
• MarkerStyle: style of temporarily thumb marker during loading process
• OnClickCell: fires when a cell is clicked
• OnDrawCell: fires when a cell is drawn
• OnMeasureThumb: fires when the size of a thumb is to be calculated
• OnProgress: fires when an image is resized to thumb format
• OnUnresolved: fires when a thumb cannot be created, e.g. when file name is not found
• RetainUnresolvedItems: keeps empty thumbs in the list
• RowHeight: the row height (equals cell height plus cell spacing)
• ParentBackground: draws the (themed) background of the parent in the border and between the cells
• Proportional: resizes images proportionally
• Sorted: file names are sorted
• Stretch: stretches small images up to the cell size
• VirtualMode: prevents of automatically creating the thumbs
• WheelScrollLines: number of rows to be scrolled with mouse wheel