Android获取本地应用并按使用频次排序

最近工作中使用到根据手机已安装应用的使用频次，然后向用户推荐这些最近使用的app。

演示效果：

整体做法：

1.通过packageManager获取手机上已安装应用
2.通过UsageStatsManager查询用户使用应用频次统计
3.按照使用频次对应用进行排序

判断用户是否开启应用使用统计权限和查询已安装应用权限

    <uses-permission android:name="android.permission.QUERY_ALL_PACKAGES"
        tools:ignore="QueryAllPackagesPermission" />

    <uses-permission android:name="android.permission.PACKAGE_USAGE_STATS"
        tools:ignore="ProtectedPermissions" />

然后跳转到权限打开页面：

询问权限

    public static boolean hasEnable(Context context) {
        if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            long ts = System.currentTimeMillis();
            UsageStatsManager usageStatsManager = (UsageStatsManager) context.getSystemService(Service.USAGE_STATS_SERVICE);
            List<UsageStats> queryUsageStats = usageStatsManager.queryUsageStats(UsageStatsManager.INTERVAL_BEST, 0, ts);
            if (queryUsageStats == null || queryUsageStats.isEmpty()) {
                return false;
            }
        }
        return true;
    }

通过packageManager获取手机上已安装应用

获取手机已安装应用

    public static ArrayList<AppInfo> getAllAppInfo(Context ctx, boolean isFilterSystem) {
        ArrayList<AppInfo> appBeanList = new ArrayList<>();
        AppInfo bean = null;

        PackageManager packageManager = ctx.getPackageManager();
        List<PackageInfo> list = packageManager.getInstalledPackages(0);
        for (PackageInfo p : list) {
            bean = new AppInfo(packageManager.getApplicationLabel(p.applicationInfo).toString(),
                    0, p.packageName, p.applicationInfo.loadIcon(packageManager));
            int flags = p.applicationInfo.flags;
            // 判断是否是属于系统的apk
            if ((flags & ApplicationInfo.FLAG_SYSTEM) != 0&&isFilterSystem) {

            } else {
                appBeanList.add(bean);
            }
        }
        return appBeanList;
    }

获取app使用频次

    @SuppressLint("WrongConstant")
    public static List<UsageStats> getUsagList(Context context) {
        UsageStatsManager manager = (UsageStatsManager) context.getSystemService("usagestats");
        long endTime = 0, startTime = 0;
        endTime = System.currentTimeMillis();
        startTime = getZeroClockTimestamp(endTime);

        List<UsageStats> usageStats = manager.queryUsageStats(UsageStatsManager.INTERVAL_DAILY, startTime, endTime);
        return usageStats;
    }

通过获取UsageStats类的mLaunchCount属性，对app进行排序：

    /**
     * 根据使用频次推荐app
     */
    private fun addRecommendApp(
        stats: UsageStats,
        localApps: MutableList<AppInfo>,
        appInfoList: List<AppInfo>
    ) {
        try {
            val count = stats.javaClass.getDeclaredField("mLaunchCount").getInt(stats)
            if (count != 0) {
                for (i in appInfoList.indices) {
                    if (stats.packageName == appInfoList[i].packageName) {
                        appInfoList[i].launchCount = count
                        localApps.add(appInfoList[i])
                    }
                }
            }
        } catch (e: IllegalAccessException) {
            e.printStackTrace()
        } catch (e: NoSuchFieldException) {
            e.printStackTrace()
        }
    }

按使用频次排序

    private fun getPackages() {
        datas.clear()
        val allAppInfo = AppHelper.getAllAppInfo(this, true)

        val usagList = AppHelper.getUsagList(applicationContext)
        usagList.forEach {
            if (!AppHelper.isSystemApp(applicationContext, it.packageName)) {
                addRecommendApp(it, datas, allAppInfo)
            }
        }
        datas.sort()
        adapter.setDatas(datas)
    }

使用的实体类：

class AppInfo(val name: String, var launchCount: Int, val packageName: String, val icon: Drawable): Comparable<Any?> {

    override operator fun compareTo(o: Any?): Int {
        return if (o is AppInfo) {
            if (launchCount > o.launchCount) -1 else 1
        } else 0
    }
}

功能实现的主要代码就是如上了，这里屏蔽了系统app，因为不过滤系统app实在是太多了。另外，adapter的代码没有贴。