feat: add loan button (undo-approval) (#860)

Fixes: #858

src/app/loans/loans-view/loan-account-actions/undo-approval/undo-approval.component.ts

@@ -0,0 +1,45 @@
+/** Angular Imports. */
+import { Component, OnInit } from '@angular/core';
+import { FormControl, FormBuilder } from '@angular/forms';
+import { ActivatedRoute, Router } from '@angular/router';
+
+/** Custom Services. */
+import { LoansService } from 'app/loans/loans.service';
+/**
+ * Undo Loan component.
+ */
+@Component({
+  selector: 'mifosx-undo-approval',
+  templateUrl: './undo-approval.component.html',
+  styleUrls: ['./undo-approval.component.scss']
+})
+export class UndoApprovalComponent implements OnInit {
+
+  /** Form Controller. */
+  note: FormControl;
+
+  /**
+   * @param loanService Loan Service.
+   * @param route Activated Route.
+   * @param router Router.
+   */
+  constructor(private loanService: LoansService,
+              private formBuilder: FormBuilder,
+              private route: ActivatedRoute,
+              private router: Router) { }
+
+  ngOnInit() {
+    this.note = this.formBuilder.control('');
+  }
+
+  /**
+   * Submits undo approval form.
+   */
+  submit() {
+    const loanId = this.route.parent.snapshot.params['loanId'];
+    this.loanService.undoLoanApproval(loanId, {'note': this.note.value}).subscribe((response: any) => {
+      this.router.navigate(['../general'], {relativeTo: this.route});
+    });
+  }
+
+}