1.使用如下方式

   /**
     * 获取应用的VersionCode
     *
     * @param context
     * @return
     */
    public static int getVersionCode(Context context) {
    
    
        PackageInfo packageInfo = getPackageInfo(context);
        return packageInfo != null ? packageInfo.versionCode : -1;
    }

    private static PackageInfo getPackageInfo(Context context) {
    
    
        try {
    
    
            return context.getPackageManager().getPackageInfo(context.getPackageName(), 0);
        } catch (PackageManager.NameNotFoundException e) {
    
    
            e.printStackTrace();
        }
        return null;
    }