Ionic 2 Updating Button Text and Event on Click - forms

Question

Sorry if this sounds very obvious but I am new to Ionic 2 / Angular 2. Upon submitting a form, I need to update the button text and click event, ie:
first click on button = submit form + update button text to "Next"
second click on button = trigger goToNext()
I managed to update the button text but not update the click event (to goToNext() ).
.html
<form (ngSubmit)="logForm(i)">
<ion-item>
<ion-input type="text" [(ngModel)]="form.userinput[i]" name="userinput[i]"></ion-input>
</ion-item>
<button ion-button block type="submit" (click)="setNext($event.target, 'Next')">Check</button>
</form>
.ts
setNext(element, text){
element.textContent = 'Next';
}
goToNext(){
// go to Next Page
}

Answer 1

Ideally you change your design a bit to keep a variable that stores state of your 'Controller'. e.g. stores PageNumber. and then behave differently based on what page you are on. So I suggest change design a bit.
But to answer your current question without major change, you can bind the handler dynamically the same way you bind the text. then in the first handler, change the handler for the next click. the default values for handler and text will decide which one is going the be used initially
handler = this.setNext;
text = 'first text';
setNext(){
alert('handler1 called');
this.handler = this.goToNext;
this.text = 'other text';
}
goToNext(){
alert('second called');
// go to Next Page
}
and in your html you go like
<button ion-button block type="submit" (click)="handler()">{{text}}</button>

Answer 2

You can use n00b answer or something like this:
in html file:
<button ion-button block type="submit" (click)="check()">{{btn_txt}}</button>
in ts file:
btn_txt = 'Check';
check() {
if (this.btn_txt == 'Check') {
//do some logic
this.btn_txt = 'Next';
} else {
console.log('go to next page');
}
}