单击按钮检查互联网连接 [英] Check internet connection on button click

问题描述

public class MainActivity extends AppCompatActivity {
    Context context;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

    }

    public void show(View v){
        if (hasActiveInternetConnection(context)){
            Toast.makeText(MainActivity.this, "Internet connection available", Toast.LENGTH_SHORT).show();
        }else{
            Toast.makeText(MainActivity.this, "Internet connection not available", Toast.LENGTH_SHORT).show();
        }
    }

    public boolean hasActiveInternetConnection(Context context) {
        if (isNetworkAvailable(context)) {

            new URLConnectTask().execute();


        } else {
           // Log.d(LOG_TAG, "No network available!");
            Toast.makeText(MainActivity.this, "No network available!", Toast.LENGTH_SHORT).show();
        }
        return false;
    }

    private class URLConnectTask extends AsyncTask<String, Void, String> {
        @Override
        protected String doInBackground(String... urls) {

            // params comes from the execute() call: params[0] is the url.
            try {
                HttpURLConnection urlc = (HttpURLConnection) (new URL("http://www.google.com").openConnection());
                urlc.setRequestProperty("User-Agent", "Test");
                urlc.setRequestProperty("Connection", "close");
                urlc.setConnectTimeout(1500);
                urlc.connect();
                String code = String.valueOf(urlc.getResponseCode() == 200);
                return code;
            } catch (IOException e) {
                //Log.e(LOG_TAG, "Error checking internet connection", e);
                //Toast.makeText(MainActivity.this, "Error checking internet connection", Toast.LENGTH_SHORT).show();
                return "Error checking internet connection";
            }
        }
    }

    private boolean isNetworkAvailable(Context context) {
        ConnectivityManager connectivityManager
                = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
        return activeNetworkInfo != null;
    }
}

我将此帖子用于Internet连接检查.但是因为他们没有使用asynctask，所以如果我使用此代码，则会得到NetworkOnMainThreadException.我尝试使用asynctask，但是现在我只收到消息"Internet连接不可用".我认为这是因为asynctask没有返回布尔值true.因此，我们将不胜感激.

I used this post for internet connectivity check. But as they are not using asynctask, if I use this code I'm getting NetworkOnMainThreadException. I tried using asynctask but now I'm only getting message "Internet connection not available". I think its because the asynctask is not returning boolean value true. So any help would be much appreciated.

推荐答案

此功能很好，您可以使用此代码

this work fine you can use this code

public boolean isConnectingToInternet(){
        ConnectivityManager connectivity = (ConnectivityManager) _context.getSystemService(Context.CONNECTIVITY_SERVICE);
          if (connectivity != null) 
          {
              NetworkInfo[] info = connectivity.getAllNetworkInfo();
              if (info != null) 
                  for (int i = 0; i < info.length; i++) 
                      if (info[i].getState() == NetworkInfo.State.CONNECTED)
                      {
                          return true;
                      }

          }
          return false;
    }

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

这篇关于单击按钮检查互联网连接的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！