Question

我正在开发一个Android项目，当我按下刷新按钮时，如果没有互联网连接，那么它必须显示一个toast messege.i实现这个，如果页面加载时没有互联网连接。但如何在刷新按钮中实现相同的代码？

this is my connection class

public class Datacon extends Activity {
public static boolean checkInternetConnection(Context context) {

    ConnectivityManager con_manager = (ConnectivityManager) context
            .getSystemService(Context.CONNECTIVITY_SERVICE);

    if (con_manager.getActiveNetworkInfo() != null
            && con_manager.getActiveNetworkInfo().isAvailable()
            && con_manager.getActiveNetworkInfo().isConnected()) {
        return true;
    } else {
        return false;
    }
}
}

这是mywebview类

public class Mywebpage<Bitmap> extends Activity {
  ProgressBar loadingProgressBar,loadingTitle;
  Boolean isInternetPresent = false;
  ConnectionDetector cd;
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
final Context context = this;
setContentView(R.layout.webviewpage);
AdView ads=(AdView)this.findViewById(R.id.adViewer);
AdRequest request=new AdRequest.Builder().build();
ads.loadAd(request);
View mActionBarView = getLayoutInflater().inflate(R.layout.my_actionbar, null);
final android.app.ActionBar actionBar = getActionBar();
actionBar.setDisplayShowHomeEnabled(false);
getActionBar().setIcon(new ColorDrawable(getResources().getColor(android.R.color.transparent))); 
actionBar.setCustomView(mActionBarView);
actionBar.setDisplayOptions(ActionBar.DISPLAY_SHOW_CUSTOM);
actionBar.setBackgroundDrawable(getResources().getDrawable(R.drawable.gradientwhite));
Button search = (Button) actionBar.getCustomView().findViewById(R.id.button1);
search.setOnClickListener(new OnClickListener() {
    public void onClick(View arg0) {
Intent inte=new Intent(Mywebpage.this,MainActivity.class);
inte.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
    startActivity(inte);
    finish();
    }
    })    ;


Bundle extras = getIntent().getExtras();
String title;
final String url;

if (!Datacon.checkInternetConnection(this)) {

    for (int i=0; i < 3; i++)
    {
          Toast.makeText(this, "Check your Internet Connection!", Toast.LENGTH_LONG).show();
    }

} else {

if (extras != null) {
    title = extras.getString("title");
    url = extras.getString("url");
    TextView text=(TextView) findViewById(R.id.textView1);
    text.setText(title);
    final WebView myWebView =(WebView)findViewById(R.id.WebView);
    myWebView.loadUrl(url);
    myWebView.getSettings().setLoadWithOverviewMode(true);
    myWebView.getSettings().setUseWideViewPort(true);
    myWebView.getSettings().setBuiltInZoomControls(true);
    myWebView.getSettings().setLayoutAlgorithm(LayoutAlgorithm.SINGLE_COLUMN); 
    loadingProgressBar=(ProgressBar)findViewById(R.id.progressBar1); 

    myWebView.setWebViewClient(new WebViewClient(){

        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            loadingProgressBar.setVisibility(View.VISIBLE);
        }

        @Override
        public void onPageFinished(WebView view, String url) {
            loadingProgressBar.setVisibility(View.GONE);
        }
        public boolean shouldOverrideUrlLoading(WebView view, String url) {
            view.loadUrl(url);
            return false;
        }
    });


Button refresh = (Button) actionBar.getCustomView().findViewById(R.id.but2);
  cd = new ConnectionDetector(getApplicationContext());
refresh.setOnClickListener(new OnClickListener() {


    @Override
    public void onClick(View v) {
         ConnectivityManager con_manager = (ConnectivityManager) context
                    .getSystemService(Context.CONNECTIVITY_SERVICE);           
         NetworkInfo netInfo = con_manager.getActiveNetworkInfo();
        String status = netInfo.getState().toString();
        if (status.equals("CONNECTED")) {
       myWebView.loadUrl(url);
        } 

        else {
            Context context_new = getApplicationContext();
            CharSequence text = "Hello toast!";
            int duration = Toast.LENGTH_SHORT;
            Toast toast = Toast.makeText(context_new, text, duration);
            toast.show();

        }


         }
    });

    }
}

} }

Answer 1

@Override
public void onClick(View v) {
ConnectivityManager cm = (ConnectivityManager)context.getSystemService(Context.CONNECTIVITY_SERVICE);
    NetworkInfo ni = cm.getActiveNetworkInfo();
    if (ni == null) {
        Toast.makeText(getActivity(), "no internet", Toast.LENGTH_SHORT).show();
    } else
        Toast.makeText(getActivity(), "internet available", Toast.LENGTH_SHORT).show();
}

Answer 2

您的onClick没有引用互联网检查方法。试试这个：

@Override
public void onClick(View v) {
    if (Datacon.checkInternetConnection(getActivity())) {
        myWebView.loadUrl(url);
    }else{
        Toast.makeText(getActivity(), "no internet", Toast.LENGTH_SHORT).show();
    }
}

Answer 3

您需要点击checkInternetConnection按钮致电Refresh：

   Context context= this;
   refresh.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                 if (!checkInternetConnection(context)) {
                        Toast.makeText(context, "No Internet connection", Toast.LENGTH_LONG).show();
                    } 
                    else{
                        myWebView.loadUrl(url);
                    }

            }
    });

Answer 4

您的refresh按钮已存在于保存Internet连接方法的活动中。所以只需在onClick中调用该方法，如：

refreshButton.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {

        if (!checkInternetConnection(getApplicationContext())) {
            Toast.makeText(getApplicationContext(), "No Internet connection", Toast.LENGTH_LONG).show();
        } 
        else{
            myWebView.loadUrl(url);
        }
    }
});

希望它有所帮助。

Android刷新按钮检查互联网连接

4 个答案: