Ionic 2 : How to use the filePicker

Question

I am using this plugin to upload files from my ios device:

https://github.com/jcesarmobile/FilePicker-Phonegap-iOS-Plugin

this is my code:

uploadResume(){
        var self = this;
        let utis = ["public.data"]

        // test
        if (this.platform.is('ios')) {
            FilePicker.pickFile(
                function (uri) {
                    let correctPath = uri.substr(0, uri.lastIndexOf('/') + 1);
                    let currentName = uri.substring(uri.lastIndexOf('/') + 1);
                    console.log(correctPath);
                    console.log(currentName);
                },
                function (error) {
                    console.log("File error : ", error)
                }
                ,
                function (utis) {
                    console.log('UTIS', this.utis)
                }
                )
        }
else{}
}

and at the top of my class I have the FilePicker declared.

declare var FilePicker: any;

@IonicPage()
@Component({
    selector: 'page-resume',
    templateUrl: 'resume.html',
})

export class ResumePage {

But its not working, nothing happens when I run it on the device. How do I fix this ?