Toward an Efficient User Interface for Block-Based Visual Programming

Block-based visual programming (BVP) is becoming popular as a basis of programming education. It allows beginners to visually construct programs without suffering from syntax errors. However, a typical user interface for BVP is inefficient partly because the users need to perform many drag-and-drop operations to put blocks on a program, and also partly because they need to find necessary blocks from many choices. To improve the efficiency of constructing programs in a BVP system, we propose a user interface that introduces three new features: (1) the semiautomatic addition of blocks; (2) the use of a pie menu to change categories of blocks; (3) the focus+context visualization of blocks in a category. We implemented a prototype BVP system with the new user interface.