I created a custom component and included it on a page.
import { Component, Input, OnInit, ViewChild, ElementRef, } from '@angular/core';
import { ActionSheetController } from 'ionic-angular'
import { APIConnection } from '../../Utils/APIConnection';
import { Http } from '@angular/http';
import { AlertController, ModalController, NavController } from 'ionic-angular';
import { AddcardPage } from '../../pages/addcard/addcard';
import { PaymentConfirmationPage } from '../../pages/payment-confirmation/payment-confirmation';
import { NewProjectPlan } from '../../Utils/NewProjectPlan'
import { FileUploader, FileItem, ParsedResponseHeaders, FileUploaderOptions } from 'ng2-file-upload/ng2-file-upload';
import { PaymentSuccessPage } from '../../pages/payment-success/payment-success';
import { DropBoxPickerPage } from '../../pages/drop-box-picker/drop-box-picker'
import { Document, DocumentUploadResponseModal } from '../../Utils/NewProjectPlan'
import { Messages } from '../../Utils/Messages'
import { DropboxToServerFileUploadListenerProvider } from '../../providers/dropbox-to-server-file-upload-listener/dropbox-to-server-file-upload-listener'
import { Subscription } from 'rxjs/Subscription';
import { GetPostKeys } from '../../Utils/APIConnection'
import { InAppBrowser } from '@ionic-native/in-app-browser';
@Component({
selector: 'project-estimate',
templateUrl: 'project-estimate.html',
})
export class ProjectEstimateComponent implements OnInit {
// Modals- Listen Parent
@Input() origin: string;
@Input() project: NewProjectPlan;
------------------------
and included using <project-estimate[project]="project" [origin]="selectedSegmentName"></project-estimate>
it is working when we using
ionic cordova build android
but the custom component not showing if we build using --prod option
ionic cordova build android --prod