Question

让我们从代码开始。这是我的主要活动：

＆＃13;

package it.mdibonito.futuroremoto;

import android.app.Activity;
import android.graphics.Bitmap;
import android.support.design.widget.TabLayout;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;

import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {

    /**
     * The {@link android.support.v4.view.PagerAdapter} that will provide
     * fragments for each of the sections. We use a
     * {@link FragmentPagerAdapter} derivative, which will keep every
     * loaded fragment in memory. If this becomes too memory intensive, it
     * may be best to switch to a
     * {@link android.support.v4.app.FragmentStatePagerAdapter}.
     */
    private SectionsPagerAdapter mSectionsPagerAdapter;

    /**
     * The {@link ViewPager} that will host the section contents.
     */
    private ViewPager mViewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        // Create the adapter that will return a fragment for each of the three
        // primary sections of the activity.
        mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());

        // Set up the ViewPager with the sections adapter.
        mViewPager = (ViewPager) findViewById(R.id.container);
        mViewPager.setAdapter(mSectionsPagerAdapter);

        TabLayout tabLayout = (TabLayout) findViewById(R.id.tabs);
        tabLayout.setupWithViewPager(mViewPager);
        //set the icons for the tabs after the  tablayout.setupWithViewPager(ViewPager)
        int number_of_tabs = 5; //this is the fixed number of tabs in the tablayout, as returned by *SectionsPagerAdapter.getCount()*
        final int[] tabIcons = new int[]{R.drawable.ic_format_list_bulleted_white_48dp, R.drawable.ic_add_location_white_48dp, R.drawable.ic_public_white_48dp, R.drawable.ic_share_white_48dp, R.drawable.ic_info_white_24dp};
        for(int i=0;i<number_of_tabs;i++){
            tabLayout.getTabAt(i).setIcon(tabIcons[i]);
        }

        FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                        .setAction("Action", null).show();
            }
        });

    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();

        //noinspection SimplifiableIfStatement
        if (id == R.id.action_settings) {
            return true;
        }

        return super.onOptionsItemSelected(item);
    }

    /**
     * A placeholder fragment containing a simple view.
     */
    public static class PlaceholderFragment extends Fragment {
        /**
         * The fragment argument representing the section number for this
         * fragment.
         */
        private static final String ARG_SECTION_NUMBER = "section_number";

        public PlaceholderFragment() {
        }

        /**
         * Returns a new instance of this fragment for the given section
         * number.
         */
        public static PlaceholderFragment newInstance(int sectionNumber) {
            PlaceholderFragment fragment = new PlaceholderFragment();
            Bundle args = new Bundle();
            args.putInt(ARG_SECTION_NUMBER, sectionNumber);
            fragment.setArguments(args);
            return fragment;
        }

        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container,
                                 Bundle savedInstanceState) {
            if (getArguments().getInt(ARG_SECTION_NUMBER) == 1) {
                View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
                return rootView;
            } else {
                if (getArguments().getInt(ARG_SECTION_NUMBER) == 2) {
                    View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
                    return rootView;
                } else if (getArguments().getInt(ARG_SECTION_NUMBER) == 3) {
                    View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
                    return rootView;
                } else if (getArguments().getInt(ARG_SECTION_NUMBER) == 4) {
                    View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
                    return rootView;
                } else if (getArguments().getInt(ARG_SECTION_NUMBER) == 5) {
                    View rootView = inflater.inflate(R.layout.fragment_programma, container, false);

                    return rootView;
                } else {
                    View rootView = inflater.inflate(R.layout.fragment_main, container, false);
                    return rootView;
                }
            }
        }
    }

    /**
     * A {@link FragmentPagerAdapter} that returns a fragment corresponding to
     * one of the sections/tabs/pages.
     */
    public class SectionsPagerAdapter extends FragmentPagerAdapter {

        public SectionsPagerAdapter(FragmentManager fm) {
            super(fm);
        }

        @Override
        public Fragment getItem(int position) {
            // getItem is called to instantiate the fragment for the given page.
            // Return a PlaceholderFragment (defined as a static inner class below).
            return PlaceholderFragment.newInstance(position + 1);
        }

        @Override
        public int getCount() {
            // Show 3 total pages.
            return 5;
        }

        @Override
        public CharSequence getPageTitle(int position) {
            switch (position) {
                case 0:
                    return "Programma";
                case 1:
                    return "Mappe";
                case 2:
                    return "Domes";
                case 3:
                    return "Social";
                case 4:
                    return "Info";
            }
            return null;
        }
    }
}

＆＃13;

这是programma.java

＆＃13;

package it.mdibonito.futuroremoto;


import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.widget.TextView;

/**
 * A simple {@link Fragment} subclass.
 */
public class programma extends Fragment {


    public programma() {
        // Required empty public constructor
    }


    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {

        View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
        WebView heroespage = (WebView) rootView.findViewById(R.id.progwebview);
        WebSettings webSettings = heroespage.getSettings();
        webSettings.setJavaScriptEnabled(true);
        heroespage.loadUrl("http://www.google.it/");

        return rootView;
    }

＆＃13;

Fragment_programma.xml

＆＃13;

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="it.mdibonito.futuroremoto.programma">

    <!-- TODO: Update blank fragment layout -->

    <WebView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/progwebview"
        android:layout_gravity="left|top" />

</FrameLayout>

＆＃13;

更多细节：我使用的是标准的Android Studio 2.1.3选项卡式活动样式，我宁愿保留它。作为标题，问题是WebView没有加载任何东西，它只显示一个白色的webview。当然，我已经添加了使用互联网进入Android清单的权限......任何帮助？

Answer 1

1。在您的myWebClient中，您已覆盖shouldOverrideUrlLoading()并始终返回true。

这意味着您不希望WebView处理此网址，而您自己会自行处理。

如果您希望WebView加载请求的网址，请在`shouldOverrideUrlLoading（）中返回false。或者甚至更好，根本不要覆盖它。

2。你确定Programma课程已经开始了吗？这是Activity，而不是Fragment。您在fragment_main活动和Programma中使用相同的布局（PlaceholderFragment）。但是，仅在Programma活动中加载网址。 PlaceholderFragment与WebView

无关

3。这就是您的PlaceholderFragment应该是这样的

public static class PlaceholderFragment extends Fragment { / ** * fragment参数表示此节的节号 *片段。 * / private static final String ARG_SECTION_NUMBER =＆＃34; section_number＆＃34 ;;

    public PlaceholderFragment() {
    }

    /**
     * Returns a new instance of this fragment for the given section
     * number.
     */
    public static PlaceholderFragment newInstance(int sectionNumber) {
        PlaceholderFragment fragment = new PlaceholderFragment();
        Bundle args = new Bundle();
        args.putInt(ARG_SECTION_NUMBER, sectionNumber);
        fragment.setArguments(args);
        return fragment;
    }

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

        View rootView = inflater.inflate(R.layout.fragment_programma, container, false);
        WebView heroespage = (WebView) rootView.findViewById(R.id.progwebview);
        WebSettings webSettings = heroespage.getSettings();
        webSettings.setJavaScriptEnabled(true);
        heroespage.loadUrl("http://www.google.it/");

        return rootView;
    }
}

Answer 2

将此代码添加到您的片段中

 @Override
public void onStart() {
    super.onStart();
    View view = getView();
    if (view != null){

      
        WebView  webView=(WebView) view.findViewById(R.id.webView);
        webView.getSettings().setJavaScriptEnabled(true);
        // Navigate anywhere you want, but consider that this classes have only been tested on YouTube's mobile site
        webView.loadUrl("www.example.com");

        // Force links and redirects to open in the WebView instead of in a browser
        webView.setWebViewClient(new WebViewClient());
    }
}

放置在片段中的WebView无法加载

2 个答案: