限制Android同步到WIFi

Question

我是Android的新手，我正在尝试编写SyncAdapter - 是否可以将SyncAdapter限制为仅在网络为WiFi（而不是3G等）时才执行同步？

Answer 1

you can make check for wifi as

    ConnectivityManager cm = (ConnectivityManager) YourActivity.this.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo info = cm.getActiveNetworkInfo();

    if(info.getType()==ConnectivityManager.TYPE_WIFI)
    {
        System.out.println("WiFi Connected");
    }
    else
    {
            System.out.println("WiFi not connected");
    }

and also add permission in manifest as

 <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"/>

Answer 2

The answer above is good, but I would add a HttpHead-Request (HTTPGet is also possible but you receive more data than needed) that is calling eg google.com so you can be sure that you are really connected to the internet. The above posted solution just checks if you have network access but does not guarantee that you have inernet access.