View 异步加载

AndroidX AsyncLayoutInflater

见 [[AsyncLayoutInflater]]

异步加载，协程

OkLayoutInflater/oklayoutinflator/src/main/java/tech/okcredit/layout_inflator/OkLayoutInflater.kt at master · okcredit/OkLayoutInflater · GitHub

View 的异步 Inflate+ 全局缓存 View：加速你的页面

• 方案：布局异步加载，全局缓存
• 存在的问题
  1. 异步 Inflater，View 使用了 Handler，通过了反射的方式，强制把后台的线程的 Looper 设置为 mainLooper，这样后台线程 new Handler() 方式也能把消息抛到主线程消息队列
  2. 异步 Inflater，在 View 中使用了 LiveData observe，注意子线程问题

  3. 全局缓存 View，View context 的问题，在全局缓存时，为了解决创建 view 的 context 不一定是 activity 导致的问题，或者是 activity 导致的内存泄露问题，对 Context 做封装：新建了 ViewContext 代理类：![image.png

     500](https://raw.githubusercontent.com/hacket/ObsidianOSS/master/obsidian202403080058213.png)

• 思路
  1. View 缓存大小控制，动态更改，LRU？
  2. View 的状态标记，方便管理 View
  3. 异步创建 View，提前缓存，减少 View inflate 的耗时
  4. 内存管理，监听 APP 内存状态，及时释放缓存
  5. RecyclerView 中的 ViewHolder
  6. 注意全局创建 View 的 LayoutParams 丢失问题

View的异步Inflate+全局缓存：加速你的页面_文化 & 方法_阿里巴巴文娱技术_InfoQ精选文章

异步加载问题

LiveData observe{} 主线程问题

异步加载的 view 中如果使用的 LiveData，注意线程 observe 问题，需要在主线程 observe。

AssertManager 锁问题

![image.png

500](https://raw.githubusercontent.com/hacket/ObsidianOSS/master/obsidian/20240312161550.png)

main (blocked)
tid=1 systid=20274 | waiting to lock <0x0052b884> (android.content.res.AssetManager) held by thread 125
Triggered ANR
main (blocked):tid=1 systid=20274 | waiting to lock <0x0052b884> (android.content.res.AssetManager) held by thread 125
       at android.content.res.AssetManager.applyStyle(AssetManager.java:1180)
       at android.content.res.ResourcesImpl$ThemeImpl.obtainStyledAttributes(ResourcesImpl.java:1355)
       at android.content.res.Resources$Theme.obtainStyledAttributes(Resources.java:1690)
       at android.content.Context.obtainStyledAttributes(Context.java:887)
       at android.view.ViewGroup$MarginLayoutParams.<init>(ViewGroup.java:8556)
       at androidx.constraintlayout.widget.ConstraintLayout$LayoutParams.<init>(ConstraintLayout.java:2910)
       at androidx.constraintlayout.widget.ConstraintLayout.generateLayoutParams(ConstraintLayout.java:1934)
       at androidx.constraintlayout.widget.ConstraintLayout.generateLayoutParams(ConstraintLayout.java:486)
       at android.view.LayoutInflater.rInflate(LayoutInflater.java:1129)
       at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1088)
       at android.view.LayoutInflater.rInflate(LayoutInflater.java:1130)
       at android.view.LayoutInflater.rInflateChildren(LayoutInflater.java:1088)
       at android.view.LayoutInflater.inflate(LayoutInflater.java:686)
       at android.view.LayoutInflater.inflate(LayoutInflater.java:538)
       at com.zzz.si_category.CategoryFragment.onCreateView(CategoryFragment.kt:119)
       at androidx.fragment.app.Fragment.performCreateView(Fragment.java:3104)
       at androidx.fragment.app.FragmentStateManager.createView(FragmentStateManager.java:524)
       at androidx.fragment.app.FragmentStateManager.moveToExpectedState(FragmentStateManager.java:261)
       at androidx.fragment.app.FragmentManager.executeOpsTogether(FragmentManager.java:1899)
       at androidx.fragment.app.FragmentManager.removeRedundantOperationsAndExecute(FragmentManager.java:1817)
       at androidx.fragment.app.FragmentManager.execSingleAction(FragmentManager.java:1729)
       at androidx.fragment.app.BackStackRecord.commitNowAllowingStateLoss(BackStackRecord.java:323)
       at com.zzz.si_main.MainTabsActivity.safeAddFragment(MainTabsActivity.kt:1736)
       at com.zzz.si_main.MainTabsActivity.initFragments(MainTabsActivity.kt:1775)
       at com.zzz.si_main.MainTabsActivity.init$lambda-23(MainTabsActivity.kt:1936)
       at com.zzz.si_main.MainTabsActivity.$r8$lambda$qCxjN0u8Pnm_kU3fyYIR-u4a2xQ(MainTabsActivity.kt)
       at com.zzz.si_main.MainTabsActivity$$InternalSyntheticLambda$0$41221826ff81153d89c8359c62d585def63fbe1a877da80880266ae3e21e8eef$2.queueIdle$bridge(MainTabsActivity.kt:8)
       at android.os.MessageQueue.next(MessageQueue.java:404)
       at android.os.Looper.loopOnce(Looper.java:161)
       at android.os.Looper.loop(Looper.java:288)
       at android.app.ActivityThread.main(ActivityThread.java:8115)
       at java.lang.reflect.Method.invoke(Native method)
       at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:703)
       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:911)