Electron IPC過多的消息

Question

我正在試驗用於構建桌面應用程序的Electron（atom shell）平臺，目前在mac os x上。

我正在嘗試它的IPC（進程間通信）模塊，用於在兩個主要電子進程，main和渲染器進程之間發送和接收同步和異步消息。

但是，對於異步消息，我得到的消息比預期的回覆已經從渲染器進程發送到主進程，並在其中進行回覆。我知道這種形式的控制檯輸出主進程應該產生的回覆。

對於DOM的2個組件中的每一個，我向主進程發送1個單個消息，並且它迴應一個應答並記錄到控制檯。但對於2個組件（反應組件），我得到4個控制檯日誌行，3個爲9，而4個則爲16個控制檯日誌消息行。

這是怎麼回事？我錯過了有關異步消息和IPC回覆的消息？同步消息和回覆沒有問題。

main.js（主處理代碼）：

var app = require('app'); // Module to control application life. 
var BrowserWindow = require('browser-window'); // Module to create native browser window. 
var ipc = require('ipc'); 

// Report crashes to our server. 
require('crash-reporter').start(); 

// Keep a global reference of the window object, if you don't, the window will 
// be closed automatically when the JavaScript object is GCed. 
var mainAppWindow = null; 
var bookWindow = null; 

// Quit when all windows are closed. 
app.on('window-all-closed', function() { 
    // On OS X it is common for applications and their menu bar 
    // to stay active until the user quits explicitly with Cmd + Q 
    app.quit(); 
}); 

// This method will be called when Electron has finished 
// initialization and is ready to create browser windows. 
app.on('ready', function() { 
    // Create the browser window. 
    mainAppWindow = new BrowserWindow({width: 1200, height: 900, 'title-bar-style': 'hidden'}); 

    // and load the index.html of the app. 
    mainAppWindow.loadUrl('file://' + __dirname + '/index.html'); 

    mainAppWindow.openDevTools(); 
    // Emitted when the window is closed. 
    mainAppWindow.on('closed', function() { 
    // Dereference the window object, usually you would store windows 
    // in an array if your app supports multi windows, this is the time 
    // when you should delete the corresponding element. 
    mainAppWindow = null; 
    app.quit(); 
    }); 

    ipc.on('asynchronous-message', function(event, arg) { 
    console.log(arg); // prints "ping" 
    event.sender.send('asynchronous-reply', 'pong'); 
    }); 


    // listen for the messages from renderer process to close the mainwindow and open a readerwindow 
    ipc.on('synchronous-message', function(event, arg) { 
    console.log(arg); // prints "ping" 
    event.returnValue = 'pong'; 
    }); 
    // when all of the book reader windows are closed open the mainAppWindow 
    // in main process listen for all bookreaderwindows are closed 
    // and in each, checking an array of them formed when they are each created. 
}); 

index.js（渲染處理代碼）：

/* 
-mainApp 
    -Controls 
    -Books 
    -Book 
*/ 
var ipc = require('ipc'); 

var Book = React.createClass({ 
    switchToBookReader: function() { 
    // close mainAppWindow, and open bookreader window. 
    // send message to main process 'close window'. 
    // listen in main process for this. 
    // callback for this in main process is to close the main window and open a readerwindow 
    }, 
    componentDidMount: function() { 
    ipc.send('asynchronous-message', 'ping'); 
    ipc.on('asynchronous-reply', function(arg) { 
     console.log(arg); // prints "pong" 
    }); 
    console.log(ipc.sendSync('synchronous-message', 'ping')); // prints "pong" 
    }, 
    render: function() { 
    return (
     <div onDoubleClick={this.switchToBookReader()} > 
     {this.props.name} 
     </div> 
    ); 
    } 
}); 

var Books = React.createClass({ 
    render: function() { 
    // create Book nodes here. 
    var bookNodes = []; 
    bookNodes.push(<Book name="book1"/>); 
    bookNodes.push(<Book name="book2"/>); 


    return (
     <div> 
     {bookNodes} 
     </div> 
    ); 
    } 
}); 

var Controls = React.createClass({ 
    render: function() { 
    return (
     <div> 
     Controls 
     </div> 
    ); 
    } 
}); 

var mainApp = React.createClass({ 
    render: function() { 
    return (
     <div> 
     <Controls /> 
     <Books /> 
     </div> 
    ); 
    } 
}); 

React.render(<mainApp />, document.body); 

Answer 1

每個聽衆創建其創建偵聽器時返回一個唯一的ID。基於此，刪除監聽器可以這樣完成：

ipcRenderer.once(channel, listener); 

爲事件添加一次性偵聽器函數。只有在下一次將消息發送到通道時纔會調用此偵聽器，然後將其刪除。

訪問https://electron.atom.io/docs/api/ipc-renderer/#ipcrendereroncechannel-listener

了這裏的解決方案和工作。