pinImage失败阻塞主线程原因
graph TD subgraph "上游代码 (问题的源头)" A[1. 录制窗口内容] --> B(2. 创建 Picture 对象); B --> C{3. 调用Bitmap.createBitmap(picture)}; C --> D[4. 生成一个'懒加载'的Hardware Bitmap]; end subgraph "你的代码 (问题的触发点)" D -- "作为 bm 参数传入" --> E(5. setThumbnail(bm, ...)); E --> F[6. new BitmapShader(bm, ...)]; F --> G[7. onDraw -> canvas.drawRoundRect]; end subgraph "渲染线程 (卡顿的发生地)" G --> H{8. RenderThread 执行 drawRoundRect}; H --> I{9. 尝试从Bitmap获取纹理 (PinAsTexture)}; I -- "Bitmap是'kLazy'类型" --> J[<b>10. PinAsTexture 失败!</b>]; J --> K[11. 触发 syncFrameState, 阻塞UI线程!]; K --> L[12. 强制光栅化Picture, 创建纹理]; L --> M[13. 完成绘制, UI线程解锁]; end style J fill:#f9f,stroke:#333,stroke-width:2px style K fill:#f9f,stroke:#333,stroke-width:2px