安卓学习笔记之读取内存信息

安卓学习笔记之读取内存信息

1. 通过context.getSystemService(Context.ACTIVITY_SERVICE)获得ActivityManager对象
2. 通过ActivityManager对象获得相关信息

获取正在运行的app个数

/** * 获取正在运行的app个数 * @return */
    public static int  getRunningAppCount(Context context) {
        ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        int count = am.getRunningAppProcesses().size();
        return count;
    }

获取手机可用内存信息 单位是bit

/** * 获取手机可用内存信息 单位是bit * @param context */
    public static long getFreeMemoryInfo(Context context){
        ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        MemoryInfo outInfo = new MemoryInfo();
        am.getMemoryInfo(outInfo );
        long availMem = outInfo.availMem;
// long totalMem = outInfo.totalMem; //低版本手机不可用
        return availMem;
    }

获取总的可用内存 单位是bit

从/proc/meminfo目录中读取信息
MemTotal: 1031016 kB
MemFree: 13548 kB
MemShared: 0 kB
Buffers: 98064 kB
Cached: 692320 kB
SwapCached: 2244 kB
Active: 563112 kB
Inact_dirty: 309584 kB
Inact_clean: 79508 kB
Inact_target: 190440 kB
HighTotal: 130992 kB
HighFree: 1876 kB
LowTotal: 900024 kB
LowFree: 11672 kB
SwapTotal: 1052248 kB
SwapFree: 1043908 kB
Committed_AS: 332340 kB

/** * 获取总的可用内存 单位是bit * @return */
    public static long getTotalMemoryInfo() {
        File file = new File("/proc/meminfo");
        BufferedReader br = null;
        try {
             br = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
             String buff;
             while ((buff = br.readLine()) != null) {
                if (buff.startsWith("MemTotal")) {  
                    String[] s = buff.split(" +");
                    return Long.parseLong(s[1])*1024;  // 获得的buff单位是kb 故要乘以1024转成b
                }
            }
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally{
            try {
                br.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return 0;
    }

获取正在运行的应用信息

public static List<AppInfo> getRunningAppInfos(Context context) {
        List<AppInfo> runningAppInfos = new ArrayList<AppInfo>();
        ActivityManager am = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        List<RunningAppProcessInfo> infos =am.getRunningAppProcesses();
        for (RunningAppProcessInfo runningAppProcessInfo : infos) {
            String processName = runningAppProcessInfo.processName;
            //获取应用占用内存信息  这个里面一共只有一个数据
            android.os.Debug.MemoryInfo[]  mem = am.getProcessMemoryInfo(new int[]{runningAppProcessInfo.pid});
//          Log.e("------>", mem[0]+"----");
            // 占用的内存
            int memorySize = mem[0].getTotalPrivateDirty() * 1024; //单位kb 需乘以1024

            PackageManager pm = context.getPackageManager();
            try {
                ApplicationInfo appInfo = pm.getApplicationInfo(processName,0);
                String packageName = appInfo.packageName;
                String appName = (String) appInfo.loadLabel(pm);
                Drawable icon = appInfo.loadIcon(pm);
                boolean isUserApp = (appInfo.flags&ApplicationInfo.FLAG_SYSTEM)==0?true:false;
                AppInfo info = new AppInfo(appName, packageName, icon, isUserApp, memorySize);
//              Log.e("-------->", "appName:"+appName+"packageName:"+packageName+"memorySize:"+memorySize);
                runningAppInfos.add(info);
            } catch (NameNotFoundException e) {
                e.printStackTrace();
            }
        }

        return runningAppInfos;
    }

判断服务是否在后台运行

/** * 判断服务是否在后台运行 * @param context * @param serviceName * @return */
    public static boolean isRunning(Context context, String serviceName) {
        ActivityManager activityManager = (ActivityManager) context.getSystemService(Context.ACTIVITY_SERVICE);
        List<RunningServiceInfo> infos = activityManager.getRunningServices(100); // 获取最多100条运行的服务
        for (RunningServiceInfo runningServiceInfo : infos) {
            String currentService = runningServiceInfo.service.getClassName();
            if (serviceName.equals(currentService)) {       //存在当前service
                return true;
            }
// System.out.println(runningServiceInfo.service.getClassName());
        }
        return false;
    }

AppInfo类

package com.yu.bean;

import android.R.drawable;
import android.graphics.drawable.Drawable;

public class AppInfo {
    /** * 应用名字 */
    private String appName;
    /** * 应用包名 */
    private String packageName;
    /** * 包内的className */
    private String className;
    /** * 应用大小 */
    private String appSize;
    /** * 应用图标 */
    private Drawable icon;
    /** * 应用存放位置 */
    private String location;
    /** * 文件目录 */
    private String sourceDir;
    /** * 是否为用户应用 是则为true */
    private boolean isUserApp;
    /** * 占用内存大小 */
    private int memorySize;
    /** * 是否选中 */
    private boolean isChecked;

    public AppInfo(String appName, String packageName, String className,
            String appSize, Drawable icon, String location, String sourceDir,
            boolean isUserApp) {
        super();
        this.appName = appName;
        this.packageName = packageName;
        this.className = className;
        this.appSize = appSize;
        this.icon = icon;
        this.location = location;
        this.sourceDir = sourceDir;
        this.isUserApp = isUserApp;
    }




    public AppInfo(String appName, String packageName, Drawable icon,
            boolean isUserApp, int memorySize) {
        super();
        this.appName = appName;
        this.packageName = packageName;
        this.icon = icon;
        this.isUserApp = isUserApp;
        this.memorySize = memorySize;
    }




    public boolean isChecked() {
        return isChecked;
    }

    public void setChecked(boolean isChecked) {
        this.isChecked = isChecked;
    }

    public int getMemorySize() {
        return memorySize;
    }


    public void setMemorySize(int memorySize) {
        this.memorySize = memorySize;
    }


    public String getAppName() {
        return appName;
    }

    public void setAppName(String appName) {
        this.appName = appName;
    }

    public String getPackageName() {
        return packageName;
    }

    public void setPackageName(String packageName) {
        this.packageName = packageName;
    }

    public String getClassName() {
        return className;
    }

    public void setClassName(String className) {
        this.className = className;
    }

    public String getAppSize() {
        return appSize;
    }

    public void setAppSize(String appSize) {
        this.appSize = appSize;
    }

    public Drawable getIcon() {
        return icon;
    }

    public void setIcon(Drawable icon) {
        this.icon = icon;
    }

    public String getLocation() {
        return location;
    }

    public void setLocation(String location) {
        this.location = location;
    }

    public String getSourceDir() {
        return sourceDir;
    }

    public void setSourceDir(String sourceDir) {
        this.sourceDir = sourceDir;
    }

    public boolean isUserApp() {
        return isUserApp;
    }

    public void setUserApp(boolean isUserApp) {
        this.isUserApp = isUserApp;
    }

    @Override
    public String toString() {
        return "AppInfo [appName=" + appName + ", packageName=" + packageName
                + ", className=" + className + ", appSize=" + appSize
                + ", icon=" + icon + ", location=" + location + ", sourceDir="
                + sourceDir + ", isUserApp=" + isUserApp + "]";
    }

}