How to get a blur event with Nativescript (IOS) - ios

Question

I need to mimic a web/browser based piece of functionality where a blur event is used to trigger some post entry-field handling.
However using a TextField with Nativescript I only have the "returnPress" event (as far as I can see from the UITextFieldDelegateImpl class source). This event works but is not what I need.
There is some interesting code in there though, especially the textFieldDidEndEditing method:
public textFieldDidEndEditing(textField: UITextField) {
let owner = this._owner.get();
if (owner) {
if (owner.updateTextTrigger === UpdateTextTrigger.focusLost) {
owner._onPropertyChangedFromNative(TextBase.textProperty, textField.text);
}
owner.dismissSoftInput();
}
}
It looks like this should be the place to fire a blur event but maybe there is some other way to accomplish what I need without messing with the framework code.

Answer 1

I did a little research and found that you could use Observable.propertyChangeEvent and the GestureModule. The next code snippets showcase the mentioned approach.
main-page.xml
<Page xmlns="http://schemas.nativescript.org/tns.xsd" navigatingTo="navigatingTo" loaded="loaded">
<StackLayout id="stack">
<Label text="Test" textWrap="true" id="label"/>
<TextField returnKeyType="done" updateTextTrigger="focusLost" hint="text" id="textfield" text="{{ textfield }}" autocorrect="false" autocapitalizationType="none" />
<TextField hint="test2" text="{{ }}" id="textfield2"/>
</StackLayout>
</Page>
main-page.js
var observable_1 = require("data/observable");
var gestures_1 = require('ui/gestures');
var textFieldEmail;
function loaded(args) {
var page = args.object;
var textField = page.getViewById("textfield");
var stackLayout = page.getViewById("stack");
var observable = new observable_1.Observable();
observable.addEventListener(observable_1.Observable.propertyChangeEvent, function (pcd) {
console.log(pcd.eventName.toString() + " " + pcd.propertyName.toString() + " " + pcd.value.toString());
});
stackLayout.on(gestures_1.GestureTypes.tap, function (args) {
console.log("Tap");
if (page.ios) {
textField.ios.resignFirstResponder();
}
else {
textField.android.clearFocus();
}
});
page.bindingContext = observable;
}
exports.loaded = loaded;