在外部事件事件中觸發Promise.fulfill

Question

我使用的聲音播放器名爲IonSound.js，可以在此處找到。 http://ionden.com/a/plugins/ion.sound/en.html

根據該文件，我可以聽sound.ended事件，像這樣：

ion.sound({ 
    sounds: [ 
     {name: "door_bump"}, 
     {name: "water_droplet_2"}, 
     {name: "water_droplet_3"} 
    ], 
    ended_callback: function (sound) { 
     // sound ended 
     game.sound.soundEnded(sound); 
    } 
}); 

我在此之上做了一個非常基本的包裝。

class Sound 
{ 
    constructor(ion) { 
     this.ion = ion; 
     this.promises = {}; 
    } 

    play(sound) { 
     if (game.settings.muted === false) { 
      this.ion.sound.play(sound); 
     } 

     this.promises[sound] = new Promise((accept, reject) => { 

     }); 

     return this.promises[sound]; 
    } 

    soundEnded(sound) { 
     if (this.events.hasOwnProperty(sound.name) === true) { 
      Promise.resolve(this.promises[sound.name]) 
     } 
    } 
} 

現在，當我執行下面的代碼：

game.sound.play("level-up"); 

ended_callback觸發器。然後它叫sound.soundEnded。

問題是，它變得像這樣一團糟。我想要做的卻是promisifying我的聲音類，所以我可以用它像這樣：

game.sound.play("level-up").then(() => { 
    console.log("Sound is over."); 
}); 

爲了做到這一點，這段代碼有fulfill()我的承諾，我一直在this.promises哈希值。

Promise.resolve(this.promises[sound.name]); 

，但它並沒有任何方法來觸發履行這樣的：

this.promises[sound.name].fulfill(); 

任何想法？

Answer 1

而不是在this.promises中保留一組承諾，請在this.promiseFulfil中保留一個承諾承諾/拒絕回調數組。這樣你就有辦法履行承諾。

這是你的類可以如何看：

class Sound 
{ 
    constructor(ion) { 
     this.ion = ion; 
     this.promiseFulfil = {}; 
    } 

    play(sound) { 
     if (game.settings.muted === false) { 
      this.ion.sound.play(sound); 
     } 

     // Just return the promise without storing it.  
     return new Promise((accept, reject) => { 
      // keep track of which function to call to fulfil promise: 
      this.promiseFulfil[sound] = { accept, reject }; 
     }); 
    } 

    soundEnded(sound) { 
     if (this.promiseFulfil[sound]) { 
      // call the appropriate promise-callback: 
      this.promiseFulfil[sound].accept(); 
      // optionally clear this entry: 
      this.promiseFulfil[sound] = undefined; 
     } 
    } 
}