2015-09-03 16:06:50 +00:00
|
|
|
# 在線/離線事件偵測
|
|
|
|
|
|
|
|
|
|
我們可以在渲染引擎 (renderer) 的行程裡用標準的 HTML5 API 來實作在線與離線事件的偵測。
|
|
|
|
|
請參考以下範例:
|
|
|
|
|
|
|
|
|
|
_main.js_
|
|
|
|
|
|
|
|
|
|
```javascript
|
2016-10-03 03:47:16 +00:00
|
|
|
var app = require('app')
|
|
|
|
|
var BrowserWindow = require('browser-window')
|
|
|
|
|
var onlineStatusWindow
|
|
|
|
|
|
|
|
|
|
app.on('ready', function () {
|
|
|
|
|
onlineStatusWindow = new BrowserWindow({ width: 0, height: 0, show: false })
|
2016-10-03 22:48:04 +00:00
|
|
|
onlineStatusWindow.loadURL(`file://${__dirname}/online-status.html`)
|
2016-10-03 03:47:16 +00:00
|
|
|
})
|
2015-09-03 16:06:50 +00:00
|
|
|
```
|
|
|
|
|
|
|
|
|
|
_online-status.html_
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<!DOCTYPE html>
|
|
|
|
|
<html>
|
|
|
|
|
<body>
|
|
|
|
|
<script>
|
|
|
|
|
var alertOnlineStatus = function() {
|
|
|
|
|
window.alert(navigator.onLine ? 'online' : 'offline');
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
window.addEventListener('online', alertOnlineStatus);
|
|
|
|
|
window.addEventListener('offline', alertOnlineStatus);
|
|
|
|
|
|
|
|
|
|
alertOnlineStatus();
|
|
|
|
|
</script>
|
|
|
|
|
</body>
|
|
|
|
|
</html>
|
|
|
|
|
```
|
|
|
|
|
|
|
|
|
|
您也許有時候也會有想要在主行程裡回應這些事件的情況。然而，在主行程裡並沒有 `navigator` 這個物件，因此不能直接地偵測這些事件。
|
|
|
|
|
但我們可以使用 Electron 所提供的跨行程 (inter-process) 溝通的工具，事件就可以被傳送到主程序內並做您所需的處理。
|
|
|
|
|
請參考以下範例:
|
|
|
|
|
|
|
|
|
|
_main.js_
|
|
|
|
|
|
|
|
|
|
```javascript
|
2016-10-03 03:47:16 +00:00
|
|
|
var app = require('app')
|
|
|
|
|
var ipc = require('ipc')
|
|
|
|
|
var BrowserWindow = require('browser-window')
|
|
|
|
|
var onlineStatusWindow
|
|
|
|
|
|
|
|
|
|
app.on('ready', function () {
|
|
|
|
|
onlineStatusWindow = new BrowserWindow({ width: 0, height: 0, show: false })
|
2016-10-03 22:48:04 +00:00
|
|
|
onlineStatusWindow.loadURL(`file://${__dirname}/online-status.html`)
|
2016-10-03 03:47:16 +00:00
|
|
|
})
|
|
|
|
|
|
|
|
|
|
ipc.on('online-status-changed', function (event, status) {
|
|
|
|
|
console.log(status)
|
|
|
|
|
})
|
2015-09-03 16:06:50 +00:00
|
|
|
```
|
|
|
|
|
|
|
|
|
|
_online-status.html_
|
|
|
|
|
|
|
|
|
|
```html
|
|
|
|
|
<!DOCTYPE html>
|
|
|
|
|
<html>
|
|
|
|
|
<body>
|
|
|
|
|
<script>
|
|
|
|
|
var ipc = require('ipc');
|
|
|
|
|
var updateOnlineStatus = function() {
|
|
|
|
|
ipc.send('online-status-changed', navigator.onLine ? 'online' : 'offline');
|
|
|
|
|
};
|
|
|
|
|
|
|
|
|
|
window.addEventListener('online', updateOnlineStatus);
|
|
|
|
|
window.addEventListener('offline', updateOnlineStatus);
|
|
|
|
|
|
|
|
|
|
updateOnlineStatus();
|
|
|
|
|
</script>
|
|
|
|
|
</body>
|
|
|
|
|
</html>
|
|
|
|
|
```
|
