Add code examples. This closes #40.

This commit is contained in:
Mikejo5001 2016-04-13 15:42:11 -07:00 committed by Nikhil Khandelwal
parent c176313d50
commit bc8923ffe1

120
README.md
View File

@ -31,8 +31,12 @@ This plugin provides an implementation of an old version of the
It provides information about the device's cellular and
wifi connection, and whether the device has an internet connection.
> To get a few ideas how to use the plugin, check out the [sample](#sample) at the bottom of this page or go straight to the [reference](#reference) content.
Report issues with this plugin on the [Apache Cordova issue tracker][Apache Cordova issue tracker].
##<a name="reference"></a>Reference
## Installation
cordova plugin add cordova-plugin-network-information
@ -214,4 +218,120 @@ When running in the Emulator, the `connection.status` is always unknown, so this
The Emulator reports the connection type as `Cellular`, which does not change, so events does _not_ fire.
## Sample: Upload a File Depending on your Network State <a name="sample"></a>
The code examples in this section show examples of changing app behavior using the online and offline events and your network connection status.
To start with, create a new FileEntry object (data.txt) to use for sample data. Call this function from the `deviceready` handler.
>*Note* This code example requires the File plugin.
```js
var dataFileEntry;
function createSomeData() {
window.requestFileSystem(window.TEMPORARY, 5 * 1024 * 1024, function (fs) {
console.log('file system open: ' + fs.name);
// Creates a new file or returns an existing file.
fs.root.getFile("data.txt", { create: true, exclusive: false }, function (fileEntry) {
dataFileEntry = fileEntry;
}, onErrorCreateFile);
}, onErrorLoadFs);
}
```
Next, add listeners for the online and offline events in the `deviceready` handler.
```js
document.addEventListener("offline", onOffline, false);
document.addEventListener("online", onOnline, false);
```
The app's `onOnline` function handles the online event. In the event handler, check the current network state. In this app, treat any connection type as good except Connection.NONE. If you have a connection, you try to upload a file.
```js
function onOnline() {
// Handle the online event
var networkState = navigator.connection.type;
if (networkState !== Connection.NONE) {
if (dataFileEntry) {
tryToUploadFile();
}
}
display('Connection type: ' + networkState);
}
```
When the online event fires in the preceding code, call the app's `tryToUploadFile` function.
If the FileTransfer object's upload function fails, call the app's `offlineWrite` function to save the current data somewhere.
>*Note* This example requires the FileTransfer plugin.
```js
function tryToUploadFile() {
// !! Assumes variable fileURL contains a valid URL to a text file on the device,
var fileURL = getDataFileEntry().toURL();
var success = function (r) {
console.log("Response = " + r.response);
display("Uploaded. Response: " + r.response);
}
var fail = function (error) {
console.log("An error has occurred: Code = " + error.code);
offlineWrite("Failed to upload: some offline data");
}
var options = new FileUploadOptions();
options.fileKey = "file";
options.fileName = fileURL.substr(fileURL.lastIndexOf('/') + 1);
options.mimeType = "text/plain";
var ft = new FileTransfer();
// Make sure you add the domain of your server URL to the
// Content-Security-Policy <meta> element in index.html.
ft.upload(fileURL, encodeURI(SERVER), success, fail, options);
};
```
Here is the code for the `offlineWrite` function.
>*Note* This code examples requires the File plugin.
```js
function offlineWrite(offlineData) {
// Create a FileWriter object for our FileEntry.
dataFileEntry.createWriter(function (fileWriter) {
fileWriter.onwriteend = function () {
console.log("Successful file write...");
display(offlineData);
};
fileWriter.onerror = function (e) {
console.log("Failed file write: " + e.toString());
};
fileWriter.write(offlineData);
});
}
```
If the offline event occurs, just do something like notify the user (for this example, just log it).
```js
function onOffline() {
// Handle the offline event
console.log("lost connection");
}
```
[Apache Cordova issue tracker]: https://issues.apache.org/jira/issues/?jql=project%20%3D%20CB%20AND%20status%20in%20%28Open%2C%20%22In%20Progress%22%2C%20Reopened%29%20AND%20resolution%20%3D%20Unresolved%20AND%20component%20%3D%20%22Plugin%20Network%20Information%22%20ORDER%20BY%20priority%20DESC%2C%20summary%20ASC%2C%20updatedDate%20DESC