Hi everybody, I am a novice in code …
I make a hidden text that appears with clicking a button (button name : “+”).
This I have achieved ! 
$w . onReady ( function () {
$w ( ‘#button’ ). onClick ( () => {
$w ( #hiddentext
). expand ();
});
});
Now I wish the button to change its name (to “-”) and when you click on it, the text disappears (initial status), and the button becomes “+” again.
it would be really great if someone could give me the rest of the code to reach my goal 
Thanks a lot
How about this…
$w.onReady(function () {
$w("#button").onClick(() => {
if ($w("#hiddentext").collapsed) {
$w(`#hiddentext`).expand();
$w("#button").label = "-";
} else {
$w(`#hiddentext`).collapse();
$w("#button").label = "+";
}
});
});
Note: to be consistent with variable naming conventions in JavaScript, you might want to rename the element ‘hiddentext’ to ‘hiddenText’, using camelcase capitalization.
Here’s the result – before click and after click:
@Jim Feuerstein,
A thousand thanks, it works perfectly with your help 
I thank you sincerely and greetings from Switzerland.
NB. And with your note, I renamed elements using camelcase capitalization.