Image formats following can be opened by double-clicking their icons:
tiff, jpg, pdf, png, gif, bmp, pict, JPEG2000(jp2, jpc, j2k), eps
svg, jbig(bie), pcx, pcd, pnm(ppm, pbm, pgm), xbm, mag, and SUN Rasterfile
Note: MAG was an image format used in Japan, especially on old NEC-PCs.
To activate ToyViewer by double-clicking icons, set ToyViewer as the default tool using "File / Show Info" (cmd-I) menu of the Finder.
ToyViewer can open image files by selecting "File / Open" of the menu.
Image files can also be opened by dragging their icons onto the icon of ToyViewer placed on Dock, Finder, or Desktop.
Some image files would have extensions that could not be recognized by ToyViewer, and some files don't have any extensions. In such cases, these files can be opened by drag & drop.
If you want to scan the contents of a folder, you can open the folder by selecting via the open panel, or by drag & drop.
If a tiff, pict, pdf, or eps image is copied into the pasteboard (by copy operation), you can display the image in a new window by clicking "File / Open Pasteboard" of the menu (or Cmd-Shift-V).
For example, if you select and copy some objects on OmniGraffle and then do "Open Pasteboard", them are displayed in a pdf image. And if you copy a still image of a movie played on QuickTime Player, you can display it as a pict image.
Right-click (or control-click) ToyViewer's icon on the Dock, then you can see the dock menu of ToyViewer. On Mac OS X 10.5 or earlier, press (click and continue pressing the mouse button) the icon on the Dock. The menu also has the item "Open Pasteboard".
In the submenu "File / Open Recent", names of recently used files and folders (that are scanned using the feature "Scan Folder") are listed. Small folder icons are attached to the menu items of folders. Icons of "?" show that the files are not found.
Usually names of files and folders are listed in the order of use. By clicking the menu item "Alphabetical Order", you can arrange them in alphabetical order. And, the number of names listed here is specified using Preferences panel.
The other way to open files or folders is to use the service menu. Select a file or a folder on Finder, and click "Finder / Services / Open in ToyViewer" of the menu.
On Mac OS X 10.6 (Snow Leopard), you should put a check on the button in "Keyboard Shortcuts" of System Preferences as below.