示例如下:
/view/webview/WebViewDemo5.java

/**
* WebView 通过 post 加载 url，自定义请求 header，获取或设置 cookie
* postUrl() - 通过 post 方式加载指定的 url
* loadUrl() - 追加自定义 header 并加载指定的 url
* CookieManager - 用于管理 cookie 的类
*
*
* 注：
* 1、如果以上方法均不满足需求的话，可以通过 shouldInterceptRequest() 拦截 url 然后通过 URLConnection 等类以自定义的方式请求网络并返回数据
* 2、关于 shouldInterceptRequest() 的基础请参见 view/webview/WebViewDemo5.java
*/

package com.webabcd.androiddemo.view.webview;

import androidx.appcompat.app.AppCompatActivity;
import android.os.Bundle;
import android.view.ViewGroup;
import android.webkit.CookieManager;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.TextView;

import com.webabcd.androiddemo.R;
import com.webabcd.androiddemo.utils.Helper;

public class WebViewDemo5 extends AppCompatActivity {

private TextView mTextView1;
private WebView mWebView1;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view_webview_webviewdemo5);

mWebView1 = findViewById(R.id.webView1);
mTextView1 = findViewById(R.id.textView1);

sample();
}

private void sample() {
// 启用 javascript 支持
WebSettings webSettings = mWebView1.getSettings();
webSettings.setJavaScriptEnabled(true);

// postUrl() - 通过 post 方式加载指定的 url
final String url = "https://www.baidu.com";
String postData = "p1=p1&p2=p2";
mWebView1.postUrl(url, Helper.stringToBytes(postData));

// loadUrl() - 追加自定义 header 并加载指定的 url
// Map<String, String> headers = new HashMap<String, String>();
// headers.put("custom-header", "test");
// mWebView1.loadUrl(url, headers);

// 设置 cookie
CookieManager cookieManager = CookieManager.getInstance();
cookieManager.setAcceptCookie(true);
cookieManager.setCookie(url, "mycookie=webabcd");
// 清除全部 cookie
// cookieManager.removeAllCookies(null);
// 持久化设置好的 cookie
cookieManager.flush();

// 获取 cookie
mWebView1.setWebViewClient(new WebViewClient() {
// 本例是在页面加载完成后获取 cookie 的，正常来说服务端是通过 response header 设置 cookie 的，所以拿到 response header 后就能拿到最新的 cookie 了
@Override
public void onPageFinished(WebView view, String url) {
CookieManager cookieManager = CookieManager.getInstance();
String cookieString = cookieManager.getCookie(url);
mTextView1.setText(cookieString);
}
});
}

// 释放资源
@Override
protected void onDestroy() {
// 从父容器中移除 WebView
((ViewGroup) mWebView1.getParent()).removeView(mWebView1);
// 移除 WebView 内的所有控件
mWebView1.removeAllViews();
// destroy() - 销毁
mWebView1.destroy();
mWebView1 = null;

super.onDestroy();
}
}
/layout/activity_view_webview_webviewdemo5.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">

<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<WebView
android:id="@+id/webView1"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

</LinearLayout>
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<pre><span style="color: #000000;">
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