Android WebView支持网站推送通知时无法触发权限申请问题求助

核心问题说明 #

默认WebView未开启网页权限请求处理逻辑，仅配置WebViewClient无法响应网页的通知权限申请，需补充WebChromeClient实现、系统权限申请、通知展示三部分逻辑。

具体修改步骤 #

1. 修改AndroidManifest.xml添加权限 #

在原有基础上添加通知相关权限，适配不同安卓版本：

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.neurofinance">
    <uses-permission android:name="android.permission.INTERNET"/>
    <!-- 新增通知权限 -->
    <uses-permission android:name="android.permission.POST_NOTIFICATIONS" />
    <uses-permission android:name="android.permission.VIBRATE" />
    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".MainActivity"
            android:configChanges="orientation|keyboardHidden|screenSize">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>
</manifest>

2. 修改MainActivity.java补充逻辑 #

需要补充三个核心逻辑：动态申请系统通知权限、配置WebChromeClient响应网页权限申请、实现通知弹出功能。修改后的完整代码如下：

package com.example.neurofinance;

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.app.ActivityCompat;
import androidx.core.app.NotificationCompat;
import androidx.core.content.ContextCompat;

import android.annotation.TargetApi;
import android.app.NotificationChannel;
import android.app.NotificationManager;
import android.content.Context;
import android.content.pm.PackageManager;
import android.net.http.SslError;
import android.os.Build;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.webkit.JavascriptInterface;
import android.webkit.PermissionRequest;
import android.webkit.SslErrorHandler;
import android.webkit.WebChromeClient;
import android.webkit.WebResourceRequest;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
    private static final int NOTIFICATION_PERMISSION_CODE = 1001;
    private static final String CHANNEL_ID = "web_notification_channel";
    private WebView webView;

    public class WebAppInterface {
        Context mContext;
        NotificationManager notificationManager;

        WebAppInterface(Context c) {
            mContext = c;
            notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
            createNotificationChannel();
        }

        // 供网页调用弹出通知
        @JavascriptInterface
        public void showNotification(String title, String content) {
            NotificationCompat.Builder builder = new NotificationCompat.Builder(mContext, CHANNEL_ID)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(title)
                    .setContentText(content)
                    .setPriority(NotificationCompat.PRIORITY_DEFAULT)
                    .setAutoCancel(true);
            if (ActivityCompat.checkSelfPermission(mContext, android.Manifest.permission.POST_NOTIFICATIONS) == PackageManager.PERMISSION_GRANTED) {
                notificationManager.notify((int) System.currentTimeMillis(), builder.build());
            }
        }

        @JavascriptInterface
        public void showToast(String toast) {
            Toast.makeText(mContext, toast, Toast.LENGTH_SHORT).show();
        }

        // 创建安卓8及以上所需的通知渠道
        private void createNotificationChannel() {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                CharSequence name = "网页通知";
                String description = "展示网页推送的通知";
                int importance = NotificationManager.IMPORTANCE_DEFAULT;
                NotificationChannel channel = new NotificationChannel(CHANNEL_ID, name, importance);
                channel.setDescription(description);
                notificationManager.createNotificationChannel(channel);
            }
        }
    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        return true;
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        this.getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN);

        // 先申请系统层面的通知权限
        checkNotificationPermission();

        webView = findViewById(R.id.webView);
        webView.addJavascriptInterface(new WebAppInterface(this), "Android");

        webView.getSettings().setDomStorageEnabled(true);
        webView.getSettings().setJavaScriptEnabled(true);
        webView.getSettings().setUseWideViewPort(true);
        webView.getSettings().setLoadWithOverviewMode(true);
        webView.setInitialScale(1);
        webView.getSettings().setBuiltInZoomControls(true);

        webView.loadUrl("www.URL.com");

        WebViewClient webViewClient = new WebViewClient() {
            @SuppressWarnings("deprecation")
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                view.loadUrl(url);
                return true;
            }

            @Override
            public void onReceivedSslError(WebView view, SslErrorHandler handler, SslError error) {
                handler.proceed();
            }

            @TargetApi(Build.VERSION_CODES.N)
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
                view.loadUrl(request.getUrl().toString());
                return true;
            }
        };
        webView.setWebViewClient(webViewClient);

        // 新增WebChromeClient处理网页权限请求
        webView.setWebChromeClient(new WebChromeClient() {
            @Override
            public void onPermissionRequest(PermissionRequest request) {
                if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                    // 允许网页的通知权限申请
                    for (String res : request.getResources()) {
                        if (res.equals(PermissionRequest.RESOURCE_NOTIFICATION)) {
                            request.grant(new String[]{PermissionRequest.RESOURCE_NOTIFICATION});
                            return;
                        }
                    }
                    super.onPermissionRequest(request);
                }
            }
        });

        if (Build.VERSION.SDK_INT >= 21)
            webView.getSettings().setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW);
    }

    // 动态申请系统通知权限
    private void checkNotificationPermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
            if (ContextCompat.checkSelfPermission(this, android.Manifest.permission.POST_NOTIFICATIONS) != PackageManager.PERMISSION_GRANTED) {
                ActivityCompat.requestPermissions(this, new String[]{android.Manifest.permission.POST_NOTIFICATIONS}, NOTIFICATION_PERMISSION_CODE);
            }
        }
    }

    @Override
    public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
        if (requestCode == NOTIFICATION_PERMISSION_CODE) {
            if (grantResults.length > 0 && grantResults[0] != PackageManager.PERMISSION_GRANTED) {
                Toast.makeText(this, "未授予通知权限，无法接收网页推送", Toast.LENGTH_SHORT).show();
            }
        }
    }
}

适配说明 #

如果网页使用的是标准的JS通知API（Notification），完成上述配置后即可正常触发权限申请弹窗；若网页有自定义的通知逻辑，可直接调用暴露的Android.showNotification(title, content)方法弹出系统通知。

内容的提问来源于stack exchange，提问作者ElonMuskofBadIdeas