MobX store

Store.js

class Store {

    /**********************************
     * BASE VALUES
     **********************************/

    @observable bpm = 120;
    @observable playing = false;

    /**********************************
     * COMPUTED VALUES
     **********************************/

    @computed get msPerClick() {
        return 60000 / this.bpm;
    }

    @computed get playButtonIcon() {
        return this.playing ? 'stop' : 'play';
    }

    @computed get bpmString() {
        return (this.bpm) ? this.bpm.toString() : '';
    }

    /**********************************
     * ACTIONS
     **********************************/

    @action togglePlaying() {
        this.playing = !this.playing;
    }

    @action setBpmFromString(bpmString) {
        this.bpm = parseFloat(bpmString) || null;
    }

    @action clampBpm() {
        this.bpm = clamp(this.bpm, 1, 999.999);
    }
}