Mode Switching: Explicit and Implicit

Description of mode switching: explicit and implicit.

Because users employ the tablet pen for both ink input and selection on the same surface, they must be able to switch quickly and easily between these functions. You can use explicit and implicit mode switching to accomplish this. Applications should always support explicit modes because they are predictable, can be learned, and do not interfere with a smooth, uninterrupted ink experience. You may also provide implicit mode switching as another way to switch modes.

Your application should provide explicit mode switching between laying down ink (both pen and highlighter), erasing, and selecting and editing. Microsoft® recommends that you:

• Use the recommended user interface (UI) for explicit mode switching. This method provides buttons on the toolbar (as well as associated menu commands) to switch from one mode to another.

  

• Provide cursor feedback on a mode switch. For example, your applications cursor should change into an eraser cursor in erase mode.

• Ensure that your application also provides mode switching options by using shortcut menus.

Microsoft usability research shows that users are comfortable with a manual switch. Explicit mode switches are easy to understand, learn, and use. Explicit modes are very common in Microsoft Windows® applications. However, explicit modes are less convenient with a tablet pen than with a mouse because increased hand movement is necessary to switch modes.

Switching between laying down ink and selecting items is the most frequent task. This is especially true for more advanced users who become familiar with ink and its capabilities on Tablet PC. For that reason, consider allowing implicit mode switches from ink to selecting by using a press-and-hold pen action. Implicit mode switching may be used as a shortcut. Operations exposed by implicit mode switching should be available through other UI elements, such as menus or buttons.

Implicit mode switches, if ill-designed, may cause the user to unexpectedly and unintentionally switch modes while laying down ink. If your application supports implicit mode switching on an ink-enabled surface, Microsoft recommends minimizing unintentional activation by limiting behaviors to the following:

• The right-click (secondary) mouse action causes the application to enter a temporary selection mode. The user activates a right-click mouse action by performing either a press-and-hold gesture or a combination of pressing a button on a pen and tapping. However, you cannot assume that all tablet pens have a button. The temporary selection mode enabled by a right-click mouse action may be a mode in which:

  • Any underlying object is selected.

    

  • The user returns to the previous mode by tapping outside the menu or the selected object.

• While one or more Ink objects are selected in selection mode, the user can:
  • Manipulate the selection or use it as an object of a command.
  • Tap outside the selection to return to ink input mode but keep the object selected.
  • Use a press-and-hold action to display a shortcut menu of available operations for the selection.

In both ink and selection modes, consider providing a shortcut for activating a selection tool. For example, the combination of press and hold followed by dragging on white space (not on an Ink object) may start either a rectangle or lasso selection.