You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
40 lines
1.1 KiB
40 lines
1.1 KiB
export class TrackedState {
|
|
constructor(callbackMethod = null, callbackScope = null) {
|
|
this.lastSeenValue = null;
|
|
|
|
if (callbackMethod) {
|
|
this.callback = callbackMethod;
|
|
if (callbackScope) {
|
|
this.callback = this.callback.bind(callbackScope);
|
|
}
|
|
}
|
|
}
|
|
|
|
set(value, changeHandler = null, changeScope = null) {
|
|
if (value !== this.lastSeenValue) {
|
|
// Copy value since the changeHandler call could actually modify our lastSeenValue
|
|
const valueCopy = value;
|
|
this.lastSeenValue = value;
|
|
if (changeHandler) {
|
|
if (changeScope) {
|
|
changeHandler.call(changeScope, valueCopy);
|
|
} else {
|
|
changeHandler(valueCopy);
|
|
}
|
|
} else if (this.callback) {
|
|
this.callback(value);
|
|
} else {
|
|
assert(false, "No callback specified");
|
|
}
|
|
}
|
|
}
|
|
|
|
setSilent(value) {
|
|
this.lastSeenValue = value;
|
|
}
|
|
|
|
get() {
|
|
return this.lastSeenValue;
|
|
}
|
|
}
|