Simon Lei enhanced the DatePicker component in the Tencent/tdesign-vue-next repository by introducing new onMonthChange and onYearChange APIs, allowing applications to respond to changes in the displayed month or year. Using TypeScript and Vue.js, Simon implemented event emissions for month and year navigation, addressing a gap where previous and next month clicks did not trigger updates. He also created a usage example to demonstrate these new callbacks, updated both English and Chinese documentation, and performed lint cleanups and minor UI adjustments. This work improved user experience and integration flexibility, reflecting a focused and well-scoped engineering contribution.