A history-of-user-operations function helps make applications easier to use. For example, users may have access to an operation history list in an application to undo or redo a past operation. To provide an overview of a long operation history and help users find target interactions or application states quickly, visual representations of operation history have been proposed. However, most previous systems are tightly integrated with target applications and difficult to apply to new applications. We propose an application-independent method that can visualize the operation history of arbitrary GUI applications by monitoring the input and output GUI events from outside of the target application. We implemented a prototype system that visualizes operation sequences of generic Java Awt/Swing applications using an annotated comic strip metaphor. We tested the system with various applications and present results from a user study.
We present the design of Lineogrammer, a diagram-drawing system motivated by the immediacy and fluidity of pencil-drawing. We attempted for Lineogrammer to feel like a modeless diagramming "medium" in which stylus input is immediately interpreted as a command, text label or a drawing element, and drawing elements snap to or sculpt from existing elements. An inferred dual representation allows geometric diagram elements, no matter how they were entered, to be manipulated at granularities ranging from vertices to lines to shapes. We also integrate lightweight tools, based on rulers and construction lines, for controlling higher-level diagram attributes, such as symmetry and alignment. We include preliminary usability observations to help identify areas of strength and weakness with this approach.