Application的onLowMemory从Android API 34开始系统不再触发，从API 35开始废弃

Application的onLowMemory从Android API 34开始系统不再触发，从API 35开始废弃

Android的Application的onLowMemory()是在ComponentCallbacks定义实现，源代码链接 https://android.googlesource.com/platform/frameworks/base/+/master/core/java/android/content/ComponentCallbacks.java ：

package android.content;import android.annotation.NonNull;
import android.content.res.Configuration;/*** The set of callback APIs that are common to all application components* ({@link android.app.Activity}, {@link android.app.Service},* {@link ContentProvider}, and {@link android.app.Application}).** <p class="note"><strong>Note:</strong> You should also implement the {@link* ComponentCallbacks2} interface, which provides the {@link* ComponentCallbacks2#onTrimMemory} callback to help your app manage its memory usage more* effectively.</p>*/
public interface ComponentCallbacks {/*** Called by the system when the device configuration changes while your* component is running.  Note that, unlike activities, other components* are never restarted when a configuration changes: they must always deal* with the results of the change, such as by re-retrieving resources.** <p>At the time that this function has been called, your Resources* object will have been updated to return resource values matching the* new configuration.** <p>For more information, read <a href="{@docRoot}guide/topics/resources/runtime-changes.html"* >Handling Runtime Changes</a>.** @param newConfig The new device configuration.*/void onConfigurationChanged(@NonNull Configuration newConfig);/*** This is called when the overall system is running low on memory, and* actively running processes should trim their memory usage.  While* the exact point at which this will be called is not defined, generally* it will happen when all background process have been killed.* That is, before reaching the point of killing processes hosting* service and foreground UI that we would like to avoid killing.** @deprecated Since API level 14 this is superseded by*             {@link ComponentCallbacks2#onTrimMemory}.*             Since API level 34 this is never called.*             Apps targeting API level 34 and above may provide an empty implementation.*/@Deprecatedvoid onLowMemory();
}

关于onLowMemory()，Android系统源代码这么说：

  * @deprecated Since API level 14 this is superseded by
     *             {@link ComponentCallbacks2#onTrimMemory}.
     *             Since API level 34 this is never called.
     *             Apps targeting API level 34 and above may provide an empty 

从 API 34开始，该方法过时了，不再被触发回调。

Android官方链接说明：

https://developer.android.com/reference/android/content/ComponentCallbacks#onLowMemory()

从API 35开始，废弃。此后这里是一个空实现。

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