Ionic Alert: Wait until button is pressed - ionic-framework

Question

I have a class Action with it's method do() wherein the IonicAlert is called.
What I want to do now is, that I call something like
Action.do().then( () => { /* do domething */ } );
but only after OK was clicked on the alert.
do(): Promise<boolean> {
let alert = this.alertCtrl.create({
buttons: [{
text: 'OK',
handler: () => {
alert.dismiss().then( () => { /* do something */ });
return false;
}
}]
});
alert.present();
return null;
}
}
I added return null; only to get no error, but of course it's not working.
Any idea, how to solve this? Thanks
PS: I also posted it to the ionic forum: https://forum.ionicframework.com/t/ionic-alert-wait-until-button-is-pressed/67448

Answer 1

Found the solution with the help of this site: https://basarat.gitbooks.io/typescript/content/docs/promise.html
do(): Promise<boolean> {
return new Promise((resolve, reject) => {
let alert = this.alertCtrl.create({
buttons: [{
text: 'OK',
handler: () => {
alert.dismiss().then(() => { resolve(true); });
return false;
}
}]
});
alert.present();
});
}
}

Answer 2

Here a version who can return true or false :
showConfirm(): Promise<boolean> {
return new Promise((resolve, reject) =>{
const confirm = this.alertCtrl.create({
title : 'Are you sure ?',
buttons: [
{
text: 'Yes',
handler:_=> resolve(true)
},
{
text: 'No',
handler:_=> resolve(false)
}
]
}).present();
})
}
To call the promise :
this.showConfirm().then((result) => {
if(result){
// do something
}
})

Answer 3

This works for me
handler: () => {
console.log(this.viewCtrl.dismiss());
}

Answer 4

That code didn't work for me in Ionic4. This did:
presentAlert():Promise<boolean> {
return new Promise((resolve, reject) => {
const ctl = this.alertController;
let alert:any = this.alertController.create({
buttons: [{
text: 'OK',
handler: () => {
ctl.dismiss().then(() => { resolve(true); });
return false;
}
}]
}).then((dlg) => dlg.present());
});
}