Version: 2022.3
LanguageEnglish
  • C#

Application.lowMemory

Suggest a change

Success!

Thank you for helping us improve the quality of Unity Documentation. Although we cannot accept all submissions, we do read each suggested change from our users and will make updates where applicable.

Close

Submission failed

For some reason your suggested change could not be submitted. Please <a>try again</a> in a few minutes. And thank you for taking the time to help us improve the quality of Unity Documentation.

Close

Cancel

Description

This event occurs when your app receives a low-memory notification from the device it is running on.

This only occurs when your app is running in the foreground. You can release non-critical assets from memory (such as, textures or audio clips) in response to this in order to avoid the app being terminated. You can also load smaller versions of such assets. Furthermore, you should serialize any transient data to permanent storage to avoid data loss if the app is terminated.

This event is supported on iOS, Android, and Universal Windows Platform (UWP).

This event corresponds to the following callbacks on the different platforms:

  • iOS: [UIApplicationDelegate applicationDidReceiveMemoryWarning]
  • Android: onLowMemory() and onTrimMemory(level == TRIM_MEMORY_RUNNING_CRITICAL)
  • UWP: MemoryManager.AppMemoryUsageIncreased (AppMemoryUsageLevel == OverLimit)

Note: For UWP, this event will not occur on Desktop and only works on memory constrained devices, such as HoloLens and Xbox One. The OverLimit threshold specified by the OS in this case is so high it is not reasonably possible to reach it and trigger the event.

Here is an example of handling the callback:

using UnityEngine;
using System.Collections;
using System.Collections.Generic;

class LowMemoryTrigger : MonoBehaviour { List<Texture2D> _textures;

private void Start() { _textures = new List<Texture2D>(); Application.lowMemory += OnLowMemory; }

private void Update() { // allocate textures until we run out of memory _textures.Add(new Texture2D(256, 256)); }

private void OnLowMemory() { // release all cached textures _textures = new List<Texture2D>(); Resources.UnloadUnusedAssets(); } }
Copyright © 2023 Unity Technologies
优美缔软件(上海)有限公司 版权所有
"Unity"、Unity 徽标及其他 Unity 商标是 Unity Technologies 或其附属机构在美国及其他地区的商标或注册商标。其他名称或品牌是其各自所有者的商标。
公安部备案号:
31010902002961