Android获取应用程序的名称，包名，版本号

主要为了获取Android手机端的应用名称，包名，版本号

private void listPackages() {
        ArrayList<PInfo> apps = getInstalledApps(false); /* false = no system packages */
        final int max = apps.size();
        for (int i=0; i<max; i++) {
            apps.get(i).prettyPrint();
        }
    }
    private ArrayList<PInfo> getInstalledApps(boolean getSysPackages) {
        ArrayList<PInfo> res = new ArrayList<PInfo>();
        List<PackageInfo> packs = getPackageManager().getInstalledPackages(0);
        for(int i=0;i<packs.size();i++) {
            PackageInfo p = packs.get(i);
            if ((!getSysPackages) && (p.versionName == null)) {
                continue ;
            }
            PInfo newInfo = new PInfo();
            newInfo.appname = p.applicationInfo.loadLabel(getPackageManager()).toString();
            newInfo.pname = p.packageName;
            newInfo.versionName = p.versionName;
            newInfo.versionCode = p.versionCode;
            newInfo.icon = p.applicationInfo.loadIcon(getPackageManager());
            res.add(newInfo);
        }
        return res;
    }