FTP Download percentage



I want to download from my FTP an image, so I use FTP from ionic-native/ftp, but when I download file (an image in this case), my percentage stays static, so I can’t know when my file is completely downloaded, but file is downloaded but i dont know when :confused: . I think I’m doing wrong, somebody can help me ? I’m new with Prosmise

        this.fTP.connect('MyMagicHost', 'MyMagicUser', 'MyMagicPass').then((res) =>{

          this.fTP.download(this.file.dataDirectory +"HelloW.JPG", '/path/to/image/59f5aa0a9fb37.jpg').then((per) => {
            if(per == 1){
              alert('Down !')
          }, (error) =>{

Thank you,