Android app性能优化之List篇 精品PPT课件

tItem for the ?first timeРgpu draw ListItemРOfficial tipsРImproving Layout PerformanceРMaking ListView Scrolling SmoothРOptimizing Layout HierarchiesРUse a Background ThreadРOptimizing Hold View Objects in a View HolderРProcessing Bitmaps Off the UI ThreadР初步优化РAvoid UI update when scrolling?避免倒计时更新/图片显示?Use a Background Thread?使用后台线程下载数据/图片РOptimizing Hold View Objects in a View Holder?ViewHolderРOptimizing Layout Hierarchies?RelativeLayout vs LinearLayout?Р深度优化Р优化measure + layout效率(HierarchyViewer)?2层布局嵌套以上避免使用RelativeLayout ?小图一个ListItem的measure时间,2.5ms-->0.7msР优化draw时间,避免image scale?滚动中不刷新图片,使用颜色占位,正确imagesize?大图listItem采取背景颜色代替图片,draw时间,7ms->2.5msР减少后台线程cpu资源占用(TraceView)?降低后台线程优先级,滚动中pause,根据cpu核心优化ThreadPoolSize?暂停后台线程时机:onTouch代替onScrollStateChangedР延迟加载图片策略,滚动停止/低速滚动?fancyРThanks!