问题描述
我们在 2.0 版的 $ git clone https://source.codeaurora.org/quic/la/camera-samples -b iot-concam-apk.lnx.1.1 中有 2 个不同的内存泄漏（看起来相同），它们在应用关闭时消失。
它们会在应用启动后立即发生。 一次又一次地切换标签页不会增加泄漏的数量，我认为这是一件好事。
我用 https://square.github.io/leakcanary/getting_started/ 抓住了它 我注意到如果我们将所有“替换”更改为添加到 onCreate 中，2 次泄漏发生在 Tab 开关上，而不是在应用启动时发生。
2021-01-28 09:21:41.781 28582-28582/com.android.example.camera2.video D/LeakCanary:
┬───
│ GC Root: System class
│
├─ android.view.inputmethod.InputMethodManager class
│ Leaking: NO (InputMethodManager↓ is not leaking and a class is never leaking)
│ ↓ static InputMethodManager.sInstance
├─ android.view.inputmethod.InputMethodManager instance
│ Leaking: NO (DecorView↓ is not leaking and InputMethodManager is a singleton)
│ ↓ InputMethodManager.mCurRootView
├─ com.android.internal.policy.DecorView instance
│ Leaking: NO (LinearLayout↓ is not leaking and View attached)
│ View is part of a window view hierarchy
│ View.mAttachInfo is not null (view attached)
│ View.mWindowAttachCount = 1
│ mContext instance of com.android.internal.policy.DecorContext,wrapping activity com.example.android.camera2.video.
│ CameraActivity with mDestroyed = false
│ ↓ DecorView.mContentRoot
├─ android.widget.LinearLayout instance
│ Leaking: NO (CameraActivity↓ is not leaking and View attached)
│ View is part of a window view hierarchy
│ View.mAttachInfo is not null (view attached)
│ View.mWindowAttachCount = 1
│ mContext instance of com.example.android.camera2.video.CameraActivity with mDestroyed = false
│ ↓ View.mContext
├─ com.example.android.camera2.video.CameraActivity instance
│ Leaking: NO (FragmentContainerView↓ is not leaking and Activity#mDestroyed is false)
│ mApplication instance of android.app.Application
│ mBase instance of android.app.ContextImpl
│ ↓ CameraActivity.container
├─ androidx.fragment.app.FragmentContainerView instance
│ Leaking: NO (View attached)
│ View is part of a window view hierarchy
│ View.mAttachInfo is not null (view attached)
│ View.mID = R.id.fragment_container
│ View.mWindowAttachCount = 1
│ mContext instance of com.example.android.camera2.video.CameraActivity with mDestroyed = false
│ ↓ View.mKeyedTags
│ ~~~~~~~~~~
├─ android.util.SparseArray instance
│ Leaking: UNKNowN
│ Retaining 3.1 kB in 117 objects
│ ↓ SparseArray.mValues
│ ~~~~~~~
├─ java.lang.Object[] array
│ Leaking: UNKNowN
│ Retaining 3.1 kB in 115 objects
│ ↓ Object[].[0]
│ ~~~
├─ androidx.navigation.NavHostController instance
│ Leaking: UNKNowN
│ Retaining 3.1 kB in 114 objects
│ mActivity instance of com.example.android.camera2.video.CameraActivity with mDestroyed = false
│ mContext instance of com.example.android.camera2.video.CameraActivity with mDestroyed = false
│ ↓ NavController.mLifecycleOwner
│ ~~~~~~~~~~~~~~~
╰→ androidx.navigation.fragment.NavHostFragment instance
Leaking: YES (ObjectWatcher was watching this because androidx.navigation.fragment.NavHostFragment received
Fragment#onDestroy() callback and Fragment#mFragmentManager is null)
Retaining 1.7 kB in 57 objects
key = 1350d8e9-4d31-42de-9bff-693ddce5f5ef
watchDurationMillis = 16748
retainedDurationMillis = 11748
MetaDATA
Build.VERSION.SDK_INT: 29
Build.MANUFACTURER: QUALCOMM
LeakCanary version: 2.6
App process name: com.android.example.camera2.video
Stats: LruCache[maxSize=3000,hits=2630,misses=44837,hitRate=5%]
RandomAccess[bytes=2279092,reads=44837,travel=13095741867,range=14884449,size=19192832]
Heap dump reason: user request
Analysis duration: 5510 ms
由于泄漏的数量没有增加并且它们在应用程序关闭时消失，我认为我们可以放任不管，但我仍然无法找到 2 次泄漏的原因。 真的是漏水吗？ 任何信息将不胜感激。
解决方法
您正在点击 this issue，这在 Navigation 2.2.3 或更高版本中是固定的。请升级到最新的稳定版 Navigation (2.3.3) 以解决此问题。
,我已经修复了内存泄漏。
不在我的 XML 中使用 androidx.fragment.app.FragmentContainerView 是解决方案。
相反，我使用了 ConstraintLayout。
如果您不使用 XML 中的 app:navGraph="@navigation/nav_graph" 控制您的片段，而是在您的活动中使用 replace<CameraFragmentSnapshot>(R.id.fragment_container,null,null)，我认为您不应该使用它