根据官方文档:https://developer.android.com/topic/performance/memory?hl=zh-cn#kotlin
import android.content.ComponentCallbacks2
// Other import statements.
class MainActivity : AppCompatActivity(), ComponentCallbacks2 {
// Other activity code.
/**
* Release memory when the UI becomes hidden or when system resources become low.
* @param level the memory-related event that is raised.
*/
override fun onTrimMemory(level: Int) {
// Determine which lifecycle or system event is raised.
when (level) {
ComponentCallbacks2.TRIM_MEMORY_UI_HIDDEN -> {
/*
Release any UI objects that currently hold memory.
The user interface moves to the background.
*/
}
ComponentCallbacks2.TRIM_MEMORY_RUNNING_MODERATE,
ComponentCallbacks2.TRIM_MEMORY_RUNNING_LOW,
ComponentCallbacks2.TRIM_MEMORY_RUNNING_CRITICAL -> {
/*
Release any memory your app doesn't need to run.
The device is running low on memory while the app is running.
The event raised indicates the severity of the memory-related event.
If the event is TRIM_MEMORY_RUNNING_CRITICAL, then the system
begins stopping background processes.
*/
}
ComponentCallbacks2.TRIM_MEMORY_BACKGROUND,
ComponentCallbacks2.TRIM_MEMORY_MODERATE,
ComponentCallbacks2.TRIM_MEMORY_COMPLETE -> {
/*
Release as much memory as the process can.
The app is on the LRU list and the system is running low on memory.
The event raised indicates where the app sits within the LRU list.
If the event is TRIM_MEMORY_COMPLETE, the process is one of the
first to be terminated.
*/
}
else -> {
/*
Release any non-critical data structures.
The app receives an unrecognized memory level value
from the system. Treat this as a generic low-memory message.
*/
}
}
}
}测试方法
adb shell am send-trim-memory com.tinytongtong.androidstudy COMPLETE
adb shell am send-trim-memory com.tinytongtong.androidstudy MODERATE
adb shell am send-trim-memory com.tinytongtong.androidstudy BACKGROUND
adb shell am send-trim-memory com.tinytongtong.androidstudy HIDDEN
adb shell am send-trim-memory com.tinytongtong.androidstudy RUNNING_CRITICAL
adb shell am send-trim-memory com.tinytongtong.androidstudy RUNNING_LOW
adb shell am send-trim-memory com.tinytongtong.androidstudy RUNNING_MODERATE