webview的使用

权限：

<!--webview必加Internet--><uses-permission android:name="android.permission.INTERNET" /><!--判断网络状态：是否有网络--><uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

监听webview的滚动：接口回调

package com.example.lenovo.mywebtest;import android.content.Context;import android.util.AttributeSet;import android.webkit.WebView;/** * 监听webview的滚动 * <p> * Created by lenovo on 2017/8/16. */public class ObserveWebView extends WebView {    private OnWebViewListener webViewListener = null;    public ObserveWebView(Context context) {        super(context);    }    public ObserveWebView(Context context, AttributeSet attrs) {        super(context, attrs);    }    public ObserveWebView(Context context, AttributeSet attrs, int defStyleAttr) {        super(context, attrs, defStyleAttr);    }    @Override    protected void onScrollChanged(int l, int t, int oldl, int oldt) {        super.onScrollChanged(l, t, oldl, oldt);        if (webViewListener != null) {            webViewListener.onScrollChanged(this, l, t, oldl, oldt);        }    }    public void setWebViewListener(OnWebViewListener webViewListener) {        this.webViewListener = webViewListener;    }    public interface OnWebViewListener {        void onScrollChanged(ObserveWebView observeWebView, int x, int y, int oldx, int oldy);    }}

加载进度条

res/drawable/progress_bar_states.xml ：

<?xml version="1.0" encoding="utf-8"?><!-- 层叠 --><layer-list xmlns:android="http://schemas.android.com/apk/res/android">    <item android:id="@android:id/background">        <shape>            <corners android:radius="2dp" />            <gradient                android:angle="270"                android:centerColor="#E3E3E3"                android:endColor="#E6E6E6"                android:startColor="#C8C8C8" />        </shape>    </item>    <item android:id="@android:id/progress">        <clip>            <shape>                <corners android:radius="2dp" />                <gradient                    android:centerColor="#4AEA2F"                    android:endColor="#31CE15"                    android:startColor="#5FEC46" />            </shape>        </clip>    </item></layer-list>

布局：

web_layout.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/tv"        android:layout_width="match_parent"        android:layout_height="80dp"        android:gravity="center"        android:text="显示还是隐藏"        android:textColor="#ff0000"        android:textSize="25sp" />    <ImageView        android:id="@+id/iv"        android:layout_gravity="center_horizontal"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:src="@drawable/ic_launcher"        android:layout_marginBottom="20dp"/>    <ProgressBar        android:id="@+id/myProgressBar"        style="?android:attr/progressBarStyleHorizontal"        android:layout_width="match_parent"        android:layout_height="3dip"        android:progressDrawable="@drawable/progress_bar_states"        android:visibility="gone" />    <com.example.lenovo.mywebtest.ObserveWebView        android:id="@+id/wv"        android:layout_width="match_parent"        android:layout_height="match_parent" /></LinearLayout>

测试类：

package com.example.lenovo.mywebtest;import android.annotation.SuppressLint;import android.app.ProgressDialog;import android.content.Context;import android.content.Intent;import android.graphics.Bitmap;import android.net.ConnectivityManager;import android.net.NetworkInfo;import android.net.Uri;import android.os.Build;import android.os.Bundle;import android.support.annotation.Nullable;import android.support.v4.app.FragmentActivity;import android.text.TextUtils;import android.util.Log;import android.view.KeyEvent;import android.view.View;import android.view.ViewTreeObserver;import android.webkit.CookieManager;import android.webkit.DownloadListener;import android.webkit.JsPromptResult;import android.webkit.JsResult;import android.webkit.WebChromeClient;import android.webkit.WebResourceRequest;import android.webkit.WebResourceResponse;import android.webkit.WebSettings;import android.webkit.WebView;import android.webkit.WebViewClient;import android.widget.ImageView;import android.widget.ProgressBar;import android.widget.TextView;public class MyWebAct extends FragmentActivity {    private ObserveWebView mWebView;    private ProgressDialog mProgressDialog;    private ProgressBar mProgressBar;    private TextView mTv;    private ImageView mIv;    private String url = "http://fu.daicash.cn/active/201709.html";    //private String url="http://old.daicash.net/app/active/201709.html";    @Override    protected void onCreate(@Nullable Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.web_layout);        mProgressBar = ((ProgressBar) this.findViewById(R.id.myProgressBar));        mWebView = ((ObserveWebView) this.findViewById(R.id.wv));        mProgressDialog = new ProgressDialog(this);        mTv = ((TextView) this.findViewById(R.id.tv));        mIv = ((ImageView) this.findViewById(R.id.iv));        setScrollBar();//滚动条的设置        initWebSetting();        setScrollListener();        mWebView.loadUrl(url);        /**         * 外交使节         */        mWebView.setWebChromeClient(new WebChromeClient() {            @Override            public void onShowCustomView(View view, CustomViewCallback callback) {                super.onShowCustomView(view, callback);            }            @Override            public boolean onJsAlert(WebView view, String url, String message, JsResult result) {                return super.onJsAlert(view, url, message, result);            }            @Override            public boolean onJsConfirm(WebView view, String url, String message, JsResult result) {                return super.onJsConfirm(view, url, message, result);            }            @Override            public boolean onJsPrompt(WebView view, String url, String message, String defaultValue, JsPromptResult result) {                return super.onJsPrompt(view, url, message, defaultValue, result);            }            @Override            public void onReceivedIcon(WebView view, Bitmap icon) {                super.onReceivedIcon(view, icon);                if (icon != null) {                    mIv.setImageBitmap(icon);                    Log.e("MyWebAct", "icon===" + icon);                }            }            @Override            public void onReceivedTitle(WebView view, String title) {                super.onReceivedTitle(view, title);                if (!TextUtils.isEmpty(title)) {                    mTv.setText(title);                    Log.e("MyWebAct", "title===" + title);                }            }            @Override            public void onProgressChanged(WebView view, int newProgress) {                //顶部添加进度条                if (newProgress == 100) {                    mProgressBar.setVisibility(View.GONE);//加载完网页进度条消失                } else {                    if (mProgressBar.getVisibility() == View.GONE) {                        mProgressBar.setVisibility(View.VISIBLE);                    }                    mProgressBar.setProgress(newProgress);//设置进度值                }                super.onProgressChanged(view, newProgress);            }        });        /**         * 内政大臣         */        mWebView.setWebViewClient(new WebViewClient() {            //控制webView是否处理按键时间,如果返回true,则WebView不处理,返回false则处理,默认false            @Override            public boolean shouldOverrideKeyEvent(WebView view, KeyEvent event) {                return super.shouldOverrideKeyEvent(view, event);            }            //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) {                if (url.trim().startsWith("tel")) {//特殊情况tel，调用系统的拨号                    Intent i = new Intent(Intent.ACTION_VIEW);                    i.setData(Uri.parse(url));                    startActivity(i);                } else {                    mWebView.loadUrl(url);                }                return true;            }            //ViewView的缩放发生改变时调用            @Override            public void onScaleChanged(WebView view, float oldScale, float newScale) {                super.onScaleChanged(view, oldScale, newScale);            }            //通知主程序WebView即将加载指定url的资源            @Override            public void onLoadResource(WebView view, String url) {                super.onLoadResource(view, url);            }            //通知应用程序内核即将加载url制定的资源，应用程序可以返回本地的资源提供给内核，若本地处理返回数据，内核不从网络上获取数据。            @Override            public WebResourceResponse shouldInterceptRequest(WebView view, WebResourceRequest request) {                return super.shouldInterceptRequest(view, request);            }            @Override            public void onPageStarted(WebView view, String url, Bitmap favicon) {                super.onPageStarted(view, url, favicon);                mProgressDialog.show();//显示进度圈            }            @Override            public void onPageFinished(WebView view, String url) {                super.onPageFinished(view, url);                mProgressDialog.dismiss();//取消进度圈                //获取webview的cookie                CookieManager cookieManager = CookieManager.getInstance();                String CookieStr = cookieManager.getCookie(url);                Log.e("MyWebAct", "Cookies = " + CookieStr);            }            //更新历史记录            @Override            public void doUpdateVisitedHistory(WebView view, String url, boolean isReload) {                super.doUpdateVisitedHistory(view, url, isReload);            }            //当浏览器访问制定的网址发生错误时会通知我们应用程序，比如网络错误。            @Override            public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {                switch (errorCode) {//                    case HttpStatus.SC_NOT_FOUND://                        view.loadUrl("file:///android_assets/error_handle.html");//                        break;                }            }        });        //页面的下载设置        mWebView.setDownloadListener(new DownloadListener() {            @Override            public void onDownloadStart(String url, String userAgent, String contentDisposition, String mimetype, long contentLength) {            }        });        //页面的回退设置        mWebView.setOnKeyListener(new View.OnKeyListener() {            @Override            public boolean onKey(View v, int keyCode, KeyEvent event) {                if (keyCode == KeyEvent.KEYCODE_BACK && mWebView != null && mWebView.canGoBack()) {                    mWebView.goBack();                    //return true表示这个事件已经被消费，不会再向上传播                    return true;                }                return false;            }        });    }    private void setScrollListener() {        mTv.setAlpha(0);        ViewTreeObserver viewTreeObserver = mTv.getViewTreeObserver();        viewTreeObserver.addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {            @SuppressWarnings("deprecation")            @Override            public void onGlobalLayout() {                mTv.getViewTreeObserver().removeGlobalOnLayoutListener(this);                final int mTitleHeight = mTv.getHeight() + mIv.getHeight();                Log.e("MyWebAct", "mTv.getHeight()===" + mTv.getHeight());                Log.e("MyWebAct", "mIv.getHeight()===" + mIv.getHeight());                mWebView.setWebViewListener(new ObserveWebView.OnWebViewListener() {                    @Override                    public void onScrollChanged(ObserveWebView observeWebView, int x, int y, int oldx, int oldy) {                        //标题随着滚动：显示与隐藏                        if (y <= 0) {                            mTv.setAlpha(0);                        } else if (y > 0 && y <= mTitleHeight) {                            float scale = (float) y / mTitleHeight;//                            Log.e("MyWebAct", "===== 透明度scale ===" + scale);                            mTv.setAlpha(scale);                        } else {                            mTv.setAlpha(1);                        }                        Log.e("MyWebAct", "===== mWebView.getContentHeight() ===" + mWebView.getContentHeight());                        Log.e("MyWebAct", "===== mWebView.getScale()===" + mWebView.getScale());                        Log.e("MyWebAct", "=====  mWebView.getHeight() ===" + mWebView.getHeight());                        Log.e("MyWebAct", "=====  mWebView.getScrollY() ===" + mWebView.getScrollY());                        Log.e("MyWebAct", "=====  mWebView.getContentHeight() * mWebView.getScale() ===" + mWebView.getContentHeight() * mWebView.getScale());                        Log.e("MyWebAct", "=====  转int的  mWebView.getContentHeight() * mWebView.getScale() ===" + (int) (mWebView.getContentHeight() * mWebView.getScale()));                        Log.e("MyWebAct", "=====  (mWebView.getHeight() + mWebView.getScrollY()===" + (mWebView.getHeight() + mWebView.getScrollY()));                        Log.e("MyWebAct", "=====  到了底部吗？===" + (mWebView.getContentHeight() * mWebView.getScale() == (mWebView.getHeight() + mWebView.getScrollY())));                        Log.e("MyWebAct", "=====  转int 到了底部吗？===" + ((int) (mWebView.getContentHeight() * mWebView.getScale()) == (mWebView.getHeight() + mWebView.getScrollY())));                        //判断到了底部,注意float转int（去掉小数）                        if ((int) (mWebView.getContentHeight() * mWebView.getScale()) == (mWebView.getHeight() + mWebView.getScrollY())) {                            Log.e("MyWebAct", "=====  已经到了底部 ===");                        }                    }                });            }        });    }    private void setScrollBar() {        // 去掉垂直滚动条        mWebView.setVerticalScrollBarEnabled(false);//默认false        // 去掉横向滚动条        mWebView.setHorizontalScrollBarEnabled(false);//默认false        // 设置WebView的一些缩放功能点//        mWebView.setScrollBarStyle(View.SCROLLBARS_OUTSIDE_OVERLAY);//滚动条在WebView内侧显示//        mWebView.setScrollBarStyle(View.SCROLLBARS_INSIDE_OVERLAY);//滚动条在WebView外侧显示    }    @SuppressLint("SetJavaScriptEnabled")    private void initWebSetting() {        WebSettings webSettings = mWebView.getSettings();         /* ------------------------------JS执行------------------------------ */         /* ------------------------------JS执行----------------------------- */        // 允许JS执行        webSettings.setJavaScriptEnabled(true);        //支持通过JS打开新窗口        webSettings.setJavaScriptCanOpenWindowsAutomatically(true);         /* ------------------------------//其他细节操作---------------------------- */         /* ------------------------------//其他细节操作----------------------------- */        //设置编码格式        webSettings.setDefaultTextEncodingName("utf-8");        //http/https混合加载        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {            webSettings.setMixedContentMode(WebSettings.MIXED_CONTENT_ALWAYS_ALLOW);        }         /* ------------------------------加快网页加载速度------------------------------ */         /* ------------------------------加快网页加载速度------------------------------ */        //noinspection deprecation        webSettings.setRenderPriority(WebSettings.RenderPriority.HIGH);//提高渲染的优先级:默认normal        //webSettings.setBlockNetworkImage(true);// 把图片加载放在最后来加载渲染        /* ------------------------------缩放------------------------------ */        /* ------------------------------缩放------------------------------ */        //自适应屏幕方式一：不推荐        //webSettings.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);        //自适应屏幕方式二：        webSettings.setUseWideViewPort(true);//设定支持viewport        webSettings.setLoadWithOverviewMode(true);   //自适应屏幕        webSettings.setSupportZoom(true); //支持缩放，默认为true。是下面那个的前提。        webSettings.setBuiltInZoomControls(true); //设置内置的缩放控件。若为false，则该WebView不可缩放,默认false        webSettings.setDisplayZoomControls(false); //隐藏原生的缩放控件，默认true        /* ------------------------------缓存------------------------------ */        /* ------------------------------缓存------------------------------ */        //Dom缓存        webSettings.setDomStorageEnabled(true);//默认false        //database缓存        webSettings.setDatabaseEnabled(true);  //默认false        //APP缓存        String appCachePath = getApplicationContext().getCacheDir().getAbsolutePath();        webSettings.setAppCachePath(appCachePath);//APP缓存路径        //noinspection deprecation        webSettings.setAppCacheMaxSize(1024 * 1024 * 10);//APP缓存大小：10M        webSettings.setAppCacheEnabled(true);//默认false        //缓存模式        if (isNetworkAvailable(this)) {            webSettings.setCacheMode(WebSettings.LOAD_DEFAULT);        } else {            webSettings.setCacheMode(WebSettings.LOAD_CACHE_ELSE_NETWORK);        }        /* ------------------------------访问文件------------------------------ */        /* ------------------------------访问文件------------------------------ */        //WebView访问文件数据        webSettings.setAllowFileAccess(true);//默认true    }    //是否有网络    public boolean isNetworkAvailable(Context context) {        ConnectivityManager connectivity = (ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);        if (connectivity == null) {            return false;        } else {            NetworkInfo info = connectivity.getActiveNetworkInfo();            if (info != null) {                if (info.getState() == NetworkInfo.State.CONNECTED) {                    return true;                }            }        }        return false;    }}