Question

我是android开发的初学者，我需要您的帮助，我有一个简单的应用程序，带有一个webview来加载本地HTML页面，我将所有文件都放在资源文件夹中，现在在我的导航抽屉中有一些文本/链接，当我点击一个链接时，我想打开这些页面。

这是我的代码：

MainActivity.java

package com.example.psalms;

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.view.Menu;
import android.webkit.WebSettings;
import android.webkit.WebView;

import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import com.google.android.material.navigation.NavigationView;

import androidx.annotation.NonNull;
import androidx.core.view.GravityCompat;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;

public class MainActivity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener{

    private AppBarConfiguration mAppBarConfiguration;

    private WebView mWebView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mWebView = (WebView) findViewById(R.id.activity_main_webview);
        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);
        FloatingActionButton fab = 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();
            }
        });
        DrawerLayout drawer = findViewById(R.id.drawer_layout);
        NavigationView navigationView = findViewById(R.id.nav_view);
        // Passing each menu ID as a set of Ids because each
        // menu should be considered as top level destinations.
        mAppBarConfiguration = new AppBarConfiguration.Builder(
                R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow)
                .setDrawerLayout(drawer)
                .build();
        NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
        NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
        NavigationUI.setupWithNavController(navigationView, navController);
        // Enable Javascript
        WebSettings webSettings = mWebView.getSettings();
        webSettings.setJavaScriptEnabled(true);
        mWebView.loadUrl("file:///android_asset/index.html");
    }

    @Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        String url = "";
        switch (item.getItemId()) {
            case R.id.nav_1: {
                url = "https://google.com";
                break;
            }
            // Add all your items as case
        }
        // We will make this method later.
        openUrl(url);
        DrawerLayout mDrawerLayout = null;
        mDrawerLayout.closeDrawer(GravityCompat.START);
        return true;
    }

    private void openUrl(final String url) {
        if (url!= null) {
            // This can also be an intent to your WebView Activity, passing the link in the extras
            Intent browserIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(url));
            startActivity(browserIntent);
        }
    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onSupportNavigateUp() {
        NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
        return NavigationUI.navigateUp(navController, mAppBarConfiguration)
                || super.onSupportNavigateUp();
    }



}

Activity_main_drawer.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    tools:showIn="navigation_view">

    <group android:checkableBehavior="single">
        <item
            android:id="@+id/nav_home"
            android:icon="@drawable/ic_menu_camera"
            android:title="@string/menu_home" />
        <item
            android:id="@+id/nav_gallery"
            android:icon="@drawable/ic_menu_gallery"
            android:title="@string/menu_gallery" />
        <item
            android:id="@+id/nav_slideshow"
            android:icon="@drawable/ic_menu_slideshow"
            android:title="@string/menu_slideshow" />
        <item
            android:id="@+id/nav_1"
            android:title="@string/psalmos1" />
    </group>
</menu>

Activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/drawer_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:openDrawer="start"
    tools:ignore="ExtraText">

    <include
        layout="@layout/app_bar_main"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />



    <WebView
        android:id="@+id/activity_main_webview"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />


    <com.google.android.material.navigation.NavigationView
        android:id="@+id/nav_view"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        android:fitsSystemWindows="true"
        app:headerLayout="@layout/nav_header_main"
        app:menu="@menu/activity_main_drawer" />

    navigationView.setNavigationItemSelectedListener(this);
</androidx.drawerlayout.widget.DrawerLayout>

Answer 1

尝试替换为：

    @Override
public boolean onNavigationItemSelected(@NonNull MenuItem item) {
    String url = "";
    switch (item.getItemId()) {
        case R.id.nav_1: {
            url = "https://google.com";
            break;
        }
        // Add all your items as case
    }
    // We will make this method later.
    openUrl(url);
    DrawerLayout mDrawerLayout = null;
    mDrawerLayout.closeDrawer(GravityCompat.START);
    return true;
}

与此：

@Override
public boolean onNavigationItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.nav_home: {
mWebView.loadUrl("file:///android_asset/index.html");
break;
}

}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}

无法通过抽屉菜单上的链接打开本地HTML页面

1 个答案: