org.reactfx.collection.ValAsList Maven / Gradle / Ivy

Go to download

Show more of this group Show more artifacts with this name
Show all versions of richtextfx Show documentation

FX-Text-Area for formatted text and other special effects.

There is a newer version: 1.11

package org.reactfx.collection;

import javafx.beans.value.ObservableValue;

import org.reactfx.Subscription;
import org.reactfx.util.Lists;
import org.reactfx.value.Val;

class ValAsList extends LiveListBase implements UnmodifiableByDefaultLiveList {
    private final ObservableValue underlying;

    ValAsList(ObservableValue underlying) {
        this.underlying = underlying;
    }

    @Override
    public int size() {
        return underlying.getValue() == null ? 0 : 1;
    }

    @Override
    public T get(int index) {
        Lists.checkIndex(index, size());
        return underlying.getValue();
    }

    @Override
    protected Subscription observeInputs() {
        return Val.observeChanges(underlying, (obs, oldVal, newVal) -> {
            if(oldVal == null) {
                assert newVal != null;
                fireElemInsertion(0);
            } else if(newVal == null) {
                assert oldVal != null; // superfluous, just for symmetry
                fireElemRemoval(0, oldVal);
            } else {
                fireElemReplacement(0, oldVal);
            }
        });
    }

}