问题背景

有网友提到：如何在HarmonyOS获取系统内存大小、可用内存？本文通过一个例子来演示解决方案。

解决方案

HarmonyOS获取手机系统内存大小的方法和Android类似。需要用到SystemMemoryInfo和iAbilityManager两个类，代码如下：

SystemMemoryInfo systemMemoryInfo = new SystemMemoryInfo();

IAbilityManager iAbilityManager = getAbilityManager();

iAbilityManager.getSystemMemoryInfo(systemMemoryInfo);

systemMemoryInfo.getTotalSysMem(); // 系统内存大小

systemMemoryInfo.getAvailSysMem(); // 可用内存大小

完整示例

创建一个名为SystemMemoryInfo的Java语言项目。修改MainAbilitySlice

代码如下：

package com.waylau.hmos.systemmemoryinfo.slice;

import com.waylau.hmos.systemmemoryinfo.ResourceTable;
import ohos.aafwk.ability.AbilitySlice;
import ohos.aafwk.ability.SystemMemoryInfo;
import ohos.aafwk.content.Intent;
import ohos.agp.components.Text;
import ohos.app.IAbilityManager;
import ohos.hiviewdfx.HiLog;
import ohos.hiviewdfx.HiLogLabel;

public class MainAbilitySlice extends AbilitySlice {
    private static final String TAG = MainAbilitySlice.class.getSimpleName();
    private static final HiLogLabel LABEL_LOG =
            new HiLogLabel(HiLog.LOG_APP, 0x00001, TAG);

    @Override
    public void onStart(Intent intent) {
        super.onStart(intent);
        super.setUIContent(ResourceTable.Layout_ability_main);

        // 添加点击事件来触发请求
        Text text = (Text) findComponentById(ResourceTable.Id_text_helloworld);
        text.setClickedListener(listener -> this.printSystemMemoryInfo());
    }

    // 打印内存信息
    private void printSystemMemoryInfo() {
        HiLog.info(LABEL_LOG, "Before printSystemMemoryInfo");
        SystemMemoryInfo systemMemoryInfo = new SystemMemoryInfo();
        IAbilityManager iAbilityManager = getAbilityManager();
        iAbilityManager.getSystemMemoryInfo(systemMemoryInfo);
        HiLog.info(LABEL_LOG, "TotalSysMem: %{public}s B", systemMemoryInfo.getTotalSysMem() );
        HiLog.info(LABEL_LOG, "AvailSysMem: %{public}s B", systemMemoryInfo.getAvailSysMem() );
        HiLog.info(LABEL_LOG, "After printSystemMemoryInfo");
    }

    @Override
    public void onActive() {
        super.onActive();
    }

    @Override
    public void onForeground(Intent intent) {
        super.onForeground(intent);
    }
}

上述代码

• 对默认生成的Id_text_helloworld文本设置点击事件，点击则会执行printSystemMemoryInfo方法。
• printSystemMemoryInfo方法使用SystemMemoryInfo、来获取 IAbilityManager系统内存大小、可用内存。

运行

运行应用，界面显示如下。点击“Hello World”本文，触发点击事件。

此时，界面切换到了搜索界面，如下。

日志输出如下：

10-19 17:26:31.555 9566-9566/com.waylau.hmos.systemmemoryinfo I 00001/MainAbilitySlice: Before printSystemMemoryInfo

10-19 17:26:31.556 9566-9566/com.waylau.hmos.systemmemoryinfo I 00001/MainAbilitySlice: TotalSysMem: 8363315200 B

10-19 17:26:31.556 9566-9566/com.waylau.hmos.systemmemoryinfo I 00001/MainAbilitySlice: AvailSysMem: 6595653632 B

10-19 17:26:31.556 9566-9566/com.waylau.hmos.systemmemoryinfo I 00001/MainAbilitySlice: After printSystemMemoryInfo

源码

上述示例源码，可以在https://github.com/waylau/harmonyos-tutorial仓库找到。