WebView

webView显示网页,
Webview加载的方式:

image.png

image.png

MainActivity*********************
···
package com.example.webviewtest;

import android.app.Dialog;
import android.content.DialogInterface;
import android.graphics.Bitmap;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.webkit.JsResult;
import android.webkit.WebChromeClient;
import android.webkit.WebResourceRequest;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.ProgressBar;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity implements View.OnClickListener{
Button bt1,bt2,bt3,bt4,bt5;
WebView webView;
LinearLayout lin;
ProgressBar pb;
ImageView img;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();

}
public void init(){
    bt1= (Button) findViewById(R.id.bt_1);
    bt1.setOnClickListener(this);
    bt2= (Button) findViewById(R.id.button2);
    bt2.setOnClickListener(this);
    bt3= (Button) findViewById(R.id.button3);
    bt3.setOnClickListener(this);
    bt4= (Button) findViewById(R.id.button4);
    bt4.setOnClickListener(this);
    bt5= (Button) findViewById(R.id.button5);
    bt5.setOnClickListener(this);
    lin= (LinearLayout) findViewById(R.id.lin);
    img= (ImageView) findViewById(R.id.imageView);
    pb= (ProgressBar) findViewById(R.id.progressBar);
    webView= (WebView) findViewById(R.id.webView);
    webView.loadUrl("http://www.baidu.com");
    webView.setWebViewClient(new WebViewClient(){
        @Override//处理连接  不写的话所有连接都会默认调用其他软件打开
        public boolean shouldOverrideUrlLoading(WebView view, WebResourceRequest request) {
            webView.loadUrl(request.getUrl().toString());
            return true;

        }

        @Override//监听网页开始加载
        public void onPageStarted(WebView view, String url, Bitmap favicon) {
            //显示布局
      lin.setVisibility(View.VISIBLE);
      pb.setMax(100);
      pb.setProgress(0);
        }

        @Override//监听网页加载结束
        public void onPageFinished(WebView view, String url) {
            super.onPageFinished(view, url);
            lin.setVisibility(View.GONE);
        }
    });
 webView.setWebChromeClient(new WebChromeClient(){
     @Override
     public void onProgressChanged(WebView view, int newProgress) {
         pb.setProgress(newProgress);
     }

     @Override//获取网址标题
     public void onReceivedTitle(WebView view, String title) {
        setTitle(title);
     }

     @Override
     public void onReceivedIcon(WebView view, Bitmap icon) {
         img.setImageBitmap(icon);
     }

     @Override
     public boolean onJsAlert(WebView view, String url, String message, JsResult result) {
         return super.onJsAlert(view, url, message, result);
     }
 });
}

@Override
public void onClick(View view) {
    switch (view.getId()){
        case R.id.bt_1://网址
           final EditText editText = new EditText(MainActivity.this);
            new AlertDialog.Builder(MainActivity.this)
                    .setTitle("请输入网址")
                    .setIcon(R.mipmap.ic_launcher_round)
                    .setView(editText)
                    .setPositiveButton("确定", new Dialog.OnClickListener() {
                        @Override
                        public void onClick(DialogInterface dialogInterface, int i) {
                            String url = editText.getText().toString();
                            if (url!=null&& !url.equals("")){

                                if (url.indexOf("http://")==0){
                                    webView.loadUrl(url);
                                }else{
                                    webView.loadUrl("http://"+url);
                                }
                            }
                        }
                    }).setNegativeButton("取消",null).show();


            break;
        case R.id.button2://刷新
            webView.reload();
            break;
        case R.id.button3://停止
            webView.stopLoading();
            break;
        case R.id.button4://前进
            if(webView.canGoForward()){
                webView.goForward();
            }else{
                Toast.makeText(this, "已经是最前面的页面了", Toast.LENGTH_SHORT).show();
            }
            break;
        case R.id.button5://后退
            if(webView.canGoBack()){
                webView.goBack();
            }else{
                Toast.makeText(this, "已经是最后一个页面了", Toast.LENGTH_SHORT).show();
            }
            break;
    }
}

}

···
xml:
···

xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.webviewtest.MainActivity">
android:id="@+id/lin"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal"
android:visibility="gone">

···