【Android】WebView

AndroidManifest.xml

允许程序打开网络套接字

网络状态



存储读写

WebViewActivity

import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.webkit.DownloadListener;
import android.webkit.JavascriptInterface;
import android.webkit.WebChromeClient;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
import android.widget.ProgressBar;
import android.widget.Toast;

public class WebViewActivity extends Activity {

    private WebView webView;
    private ProgressBar kfProgress; //进度条
    private static ProgressDialog proDialog; //加载提示框
    private long exitTime = 0; //时间
    private static String urlString = "http://www.hao123.com";
    private static String urlErrorString = "http://www.baudu.com";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_web_view);
        proDialog = android.app.ProgressDialog.show(this, "提示", "网页加载中");
        webViewInit(); //初始化web浏览器
    }

    private void webViewInit(){
        webView = (WebView) findViewById(R.id.kfWebView);
        kfProgress = (ProgressBar)findViewById(R.id.kfProgressBar);

        /*** 设置属性 ***/
        WebSettings settings = webView.getSettings();
        settings.setUseWideViewPort(true);//设定支持viewport
        settings.setLoadWithOverviewMode(true);//自适应屏幕
        settings.setBuiltInZoomControls(true);
        settings.setDisplayZoomControls(false);
        settings.setSupportZoom(true);//设定支持缩放
        settings.setDisplayZoomControls(false);//缩放控件隐藏
        settings.setDefaultTextEncodingName("UTF-8");
        settings.setJavaScriptEnabled(true); //设置WebView属性,运行执行js脚本
        settings.setCacheMode(WebSettings.LOAD_NO_CACHE); //不使用缓存,只从网络获取数据
        settings.setLoadsImagesAutomatically(true); //支持自动加载图片
        settings.setAllowFileAccess(true); //设置可以访问文件

        webView.setWebViewClient(new WebViewClient() {
            //设置在webView点击打开的新网页在当前界面显示,而不跳转到新的浏览器中
            @Override
            public boolean shouldOverrideUrlLoading(WebView view, String url) {
                view.loadUrl(url);
                return true;
            }
            //错误处理
            @Override
            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {
                super.onReceivedError(view, errorCode, description, failingUrl);
                webView.loadUrl(urlErrorString);
            }
            //webView加载完成
            @Override
            public void onPageFinished(WebView view, String url)
            {
                super.onPageFinished(view, url);
                if (proDialog != null){
                    proDialog.dismiss();
                    proDialog = null;
                }
            }
        });

        webView.setWebChromeClient(new WebChromeClient() {
            //监听网页加载
            @Override
            public void onProgressChanged(WebView view, int newProgress) {
                if(newProgress==100){
                    kfProgress.setVisibility(View.GONE);//加载完网页进度条消失
                }
                else{
                    kfProgress.setVisibility(View.VISIBLE);//开始加载网页时显示进度条
                    kfProgress.setProgress(newProgress);//设置进度值
                }
            }
        });

        /*** 监听下载 ***/
        webView.setDownloadListener(new DownloadListener(){
            @Override
            public void onDownloadStart(String url, String userAgent, String contentDisposition,String mimetype, long contentLength) {
                Toast.makeText(getApplicationContext(), "开始下载",
                        Toast.LENGTH_SHORT).show();
                Uri uri = Uri.parse(url);
                Intent intent = new Intent(Intent.ACTION_VIEW,uri);
                startActivity(intent);
            }
        });

        /*** JS交互 ***/
        webView.addJavascriptInterface(new JSBridge(),"JSObj");

        /*** 调用loadUrl方法为WebView加入链接 ***/
        webView.loadUrl(urlString);
    }

    /***
     * 当用户点击回退按钮
     */
    @Override
    public void onBackPressed() {
        if (webView.canGoBack()) {
            //判断网页是否能后退
            webView.goBack();
        } else {
            if ((System.currentTimeMillis() - exitTime) > 2000) {
                Toast.makeText(getApplicationContext(), "再按一次退出浏览器",
                        Toast.LENGTH_SHORT).show();
                exitTime = System.currentTimeMillis();
            } else {
                super.onBackPressed();
            }
        }
    }

    /**
     * js交互类
     */
    public class JSBridge{
        @JavascriptInterface
        public void openApp(String message) {

        }
    }
}

activity_web_view.xml 布局

Layout>

pg.xml 进度条设置