Traditional exercise-based approaches for teaching code writing often focus solely on writing correct code, limiting opportunities for code refinement and the essential trial-and-error process inherent in software development. To address these limitations, we previously proposed a code-sharing platform that leverages program visualization and quality-based scoring to encourage continuous code improvement. However, the previously developed text-based system posed challenges for novice programmers, including frequent syntax errors and increased cognitive load, thereby hindering effective trial-and-error learning. In the present study, we introduce an enhanced code-sharing platform that incorporates visual programming to overcome these challenges. By utilizing a block-based coding environment, the present system eliminates syntax errors and simplifies code construction, allowing learners to focus on algorithmic and logical refinement. In an evaluation involving 9 university students, we demonstrated that the visual programming approach significantly improved code quality scores, reduced time spent on code creation, and minimized syntax-related interruptions. In addition, questionnaire results indicated high levels of learner satisfaction and perceived effectiveness in promoting motivated and efficient learning. These findings suggest that visual programming, combined with a collaborative code-sharing framework, enhances programming education by facilitating better code writing and more effective learning through trial-and-error.