How to download a file with ionic 5 - ionic-framework

Question

I am trying to download a file with my ionic app, but it's not working, the file is a video file and I want to show a progress bar as its downloading, How it will work is that when a user clicks on download, it will check if the directory AppName exist, it not it will create the directory, then download the file inside the directory.
Here's my code
download() {
this.chkmkDir().then(async ()=>{
const fileTransfer: FileTransferObject = this.fileTransfer.create();
this.storageDirectory = `${this.file.dataDirectory}${api.AppName}/`;
fileTransfer.onProgress((progressEvent)=>this.progress=Math.round((progressEvent.loaded / progressEvent.total) * 100))
let fileName=await this.service.getFileName('mp4')
var URL = encodeURI('test.mp4');
fileTransfer.download(URL,`${this.storageDirectory}${fileName}`, true)
})
}
chkmkDir(){
return new Promise((resolve, reject)=>{
this.file.checkDir(this.file.dataDirectory, api.AppName).then(res=>resolve()
).catch(err => {
this.file.createDir(this.file.dataDirectory, api.AppName,false).then(res =>resolve())
.catch(err=>reject(JSON.stringify(err)));
});
})
}
Please what am I doing wrong, I got this error in the console
ERROR Error: Uncaught (in promise): TypeError: Cannot read property 'then' of undefined TypeError: Cannot read property 'then' of undefined

Answer 1

The plugin that you're using is just not there. Your code can't read the classes from the plugin. That may happen due to plugin incompatibility or other dependency issues related to plugins.
This can happen too when you didn't set or configured the plugin properly. Please check your app.module.ts file. And also check if any error related to plugin versions incompatibility is logged in the console. In a brief, all your plugins should have the same version as your "#ionic-native/core" version.
Ex:
package.json
"#ionic-native/core": "^5.0.0",
"#ionic-native/diagnostic": "^5.0.0",
"#ionic-native/dialogs": "^5.0.0",
"#ionic-native/file": "^5.0.0",
"#ionic-native/file-path": "^5.0.0",
"#ionic-native/file-transfer": "^5.0.0",
"#ionic-native/http": "^5.0.0",