Question

@Override
public void onBackPressed() {
    if (myWebView.canGoBack()) {
        myWebView.goBack();
    } else {
        super.onBackPressed();
    }
}

此代码在我的片段中无法用于支持webview中的网页

Answer 1

在WebView上使用setOnKeyListener()收听任何事件，因为onBackPreesed()不是片段的成员

        myWebView.setOnKeyListener(new View.OnKeyListener() {
           @Override
           public boolean onKey(View v, int keyCode, KeyEvent event) {
               if (event.getAction()==KeyEvent.ACTION_DOWN &&keyCode==KeyEvent.KEYCODE_BACK&&myWebView.canGoBack()) {
                  myWebView.goBack();
               }
               return true;
           }
       });

Answer 2

您需要将片段附加到相应的活动中。从您的激活

实施onBackPressed方法之后

Answer 3

package com.cornicore.dream11statistics;

import android.content.Context;
import android.graphics.Bitmap;
import android.net.Uri;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;

import com.google.android.gms.ads.AdRequest;
import com.google.android.gms.ads.AdView;
import com.google.android.gms.ads.MobileAds;


/**
 * A simple {@link Fragment} subclass.
 * Activities that contain this fragment must implement the
 * {@link Tab1.OnFragmentInteractionListener} interface
 * to handle interaction events.
 * Use the {@link Tab1#newInstance} factory method to
 * create an instance of this fragment.
 */
public class Tab1 extends Fragment {

    AdView adView_Banner;
    WebView myWebView;
    ProgressBar progressBar;

    // TODO: Rename parameter arguments, choose names that match
    // the fragment initialization parameters, e.g. ARG_ITEM_NUMBER
    private static final String ARG_PARAM1 = "param1";
    private static final String ARG_PARAM2 = "param2";

    // TODO: Rename and change types of parameters
    private String mParam1;
    private String mParam2;

    private OnFragmentInteractionListener mListener;

    public Tab1() {
        // Required empty public constructor
    }

    /**
     * Use this factory method to create a new instance of
     * this fragment using the provided parameters.
     *
     * @param param1 Parameter 1.
     * @param param2 Parameter 2.
     * @return A new instance of fragment Tab1.
     */
    // TODO: Rename and change types and number of parameters
    public static Tab1 newInstance(String param1, String param2) {
        Tab1 fragment = new Tab1();
        Bundle args = new Bundle();
        args.putString(ARG_PARAM1, param1);
        args.putString(ARG_PARAM2, param2);
        fragment.setArguments(args);
        return fragment;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        if (getArguments() != null) {
            mParam1 = getArguments().getString(ARG_PARAM1);
            mParam2 = getArguments().getString(ARG_PARAM2);
        }



    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

        View v = inflater.inflate(R.layout.fragment_tab1, container, false);



        myWebView = (WebView) v.findViewById(R.id.webViewHome);
        progressBar = (ProgressBar) v.findViewById(R.id.progressBarFragment);
        myWebView.setWebViewClient(new WebViewClient());

        WebSettings webSettings = myWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);
        webSettings.setLoadWithOverviewMode(true);
        webSettings.setUseWideViewPort(true);
        webSettings.setSupportZoom(true);
        webSettings.setBuiltInZoomControls(false);
        webSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
        webSettings.setCacheMode(WebSettings.LOAD_NO_CACHE);
        webSettings.setDomStorageEnabled(true);
        myWebView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);
        myWebView.setScrollbarFadingEnabled(true);

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT) {
            myWebView.setLayerType(View.LAYER_TYPE_HARDWARE, null);
        } else {
            myWebView.setLayerType(View.LAYER_TYPE_SOFTWARE, null);
        }



        myWebView.loadUrl("https://cornicore.com/cricket-news/");


        myWebView.setWebViewClient(new WebViewClient(){
            @Override
            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                myWebView.loadUrl("file:///android_asset/internet.html");
            }
        });


        myWebView.setWebChromeClient(new WebChromeClient() {
            public void onProgressChanged(WebView view, int progress) {
                progressBar.setProgress(progress);
                if (progress == 100) {
                    progressBar.setVisibility(View.GONE);

                } else {
                    progressBar.setVisibility(View.VISIBLE);

                }
            }
        });



        return v;
    }



    // TODO: Rename method, update argument and hook method into UI event
    public void onButtonPressed(Uri uri) {
        if (mListener != null) {
            mListener.OnNavFragmentInteractionListener(uri);
        }
    }

    @Override
    public void onAttach(Context context) {
        super.onAttach(context);
        if (context instanceof OnFragmentInteractionListener) {
            mListener = (OnFragmentInteractionListener) context;
        } else {
            throw new RuntimeException(context.toString() + " must implement OnFragmentInteractionListener");
        }
    }

    @Override
    public void onDetach() {
        super.onDetach();
        mListener = null;
    }


    public interface OnFragmentInteractionListener {
         void OnNavFragmentInteractionListener(Uri uri);

    }

    public interface OnNavFragmentInteractionListener {
    }

    public void setInteractionListener(OnFragmentInteractionListener mListener){
        this.mListener = mListener;
    }

    /**
     * This interface must be implemented by activities that contain this
     * fragment to allow an interaction in this fragment to be communicated
     * to the activity and potentially other fragments contained in that
     * activity.
     * <p>
     * See the Android Training lesson <a href=
     * "http://developer.android.com/training/basics/fragments/communicating.html"
     * >Communicating with Other Fragments</a> for more information.
     */





}

如何使用片段内的onBackPressed（）来支持webview？

3 个答案: