Android开发：原生+H5之：Android webview配置

迈不过友情╰ 2022-05-27 05:35 294阅读 0赞

在上一篇文章[Android 原生开发、H5、React-Native开发特点][Android _H5_React-Native]，我们可以了解到三种Android开发方式的区别和优缺点。**\[Android开发：原生+H5\]**系列的文章，将主要讲解Android原生+H5开发相关，这一节主要是Android原生+H5开发时要使用WebView，要使WebView正确的显示加载H5页面和功能需要做相关的配置。

## AndroidManifest权限添加 ##

请一定、务必在AndroidManifest中添加如下权限，否则是无法正常打开显示H5页面的。  
　　这个一定要单独拿出来强调一下，以防你其他代码啊，配置啊什么的都写好了，但就是不显示，然后你就各种找问题，发愁，恼怒，耽误时间。因为楼主就曾经犯过这样的错误，真的被自己粗心蠢哭，哭哭哭……

<uses-permission android:name="android.permission.INTERNET"/>

## WebView使用步骤 ##

**1. 添加AndroidManifest权限。**

<uses-permission android:name="android.permission.INTERNET"/>

**2. 布局文件**

<?xml version="1.0" encoding="utf-8"?>
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
        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.app.www.webapp.SecondActivity">
    
        <WebView
            android:id="@+id/webView"
            android:layout_width="match_parent"
            android:layout_height="match_parent" />
    
    </LinearLayout>

**3. 获取WebView对象**

webView = this.findViewById(R.id.webView);

**4. WebSettings配置WebView。**下面有具体的配置说明。  
**5. 设置加载地址。**

this.webView.loadUrl(url);

到这一步为止，WebView就可以正常的显示了，如果我们想要对WebView做进一步的监听处理，就需要下面的设置。  
　　  
**6. 设置WebViewClient。** WebViewClient主要是监听WebView加载进程，平常我们对webview加载的处理，例如加一些进度条、跳转设置之类的都是通过WebViewClient类完成。在下面我们会讲到。  
**7. 设置WebChromeClient。** 有时候我们不想原生去调用手机的拍照和相册，如果我们想要用H5去掉用的话，我们需要去重新WebChromeClient类，并进行设置，这样H5才能成功的调用拍照和相册。下面会细讲。

## WebSettings类配置 ##

/**支持Js**/
            setting.setJavaScriptEnabled(true);
    
            /**设置自适应屏幕，两者合用**/
            //将图片调整到适合webview的大小
            setting.setUseWideViewPort(true);
            // 缩放至屏幕的大小
            setting.setLoadWithOverviewMode(true);
    
            /**缩放操作**/
            // 是否支持画面缩放，默认不支持
            setting.setBuiltInZoomControls(true);
            setting.setSupportZoom(true);
            // 是否显示缩放图标，默认显示
            setting.setDisplayZoomControls(false);
            // 设置网页内容自适应屏幕大小
            setting.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
    
            /**设置允许JS弹窗**/
            setting.setJavaScriptCanOpenWindowsAutomatically(true);
            setting.setDomStorageEnabled(true);
    
            /**关闭webview中缓存**/
            setting.setCacheMode(WebSettings.LOAD_NO_CACHE);
            /**设置可以访问文件 **/
            setting.setAllowFileAccess(true);
            setting.setAllowFileAccessFromFileURLs(true);
            setting.setAllowUniversalAccessFromFileURLs(true);

## WebViewClient类 ##

如果不进行设置WebViewClient的话，我们的WebView通常会跳转到手机自带的浏览器去进行显示，但是我们想要的是在app内显示，所以我们需要对WebViewClient进行设置。对这个类的使用我们之前在[ Android 网络连接——WebView][Android _WebView]这篇文章中也讲过，这里我就只复制一下。

### WebView加载失败设置 ###

我们在使用浏览器时，我们经常会看到，如果页面加载失败会出现一个提示的页面。我们自己的浏览器当然也少不了这个功能。设置加载页面失败调用WebView的setWebViewClient()方法，传入匿名WebViewClient对象，重写onReceivedError()方法，在该方法内进行处理。

webView.setWebViewClient(new WebViewClient() {
        /*
        网络连接错误时调用
        */
        @Override
        public void onReceivedError(WebView view, int errorCode, String description, String failingUrl){
            super.onReceivedError(view, errorCode, description, failingUrl);
        }
    });

### WebView网页加载进度条显示 ###

webView.setWebChromeClient(new WebChromeClient() {
                @Override
                public void onProgressChanged(WebView view, int newProgress) {
                    super.onProgressChanged(view, newProgress);
                    progressBar.setProgress(newProgress);//网络加载时设置进度条进度
                }
            });
            webView.setWebViewClient(new WebViewClient() {
                /*
                网络开始加载时调用
                */
                @Override
                public void onPageStarted(WebView view, String url, Bitmap favicon) {
                    super.onPageStarted(view, url, favicon);
                    progressBar.setVisibility(View.VISIBLE);//设置显示进度条
                }
    
                /*
                网络加载结束时调用
                */
                @Override
                public void onPageFinished(WebView view, String url) {
                    super.onPageFinished(view, url);
                    progressBar.setVisibility(View.GONE);//设置去除进度条
                }
            });

## WebChromeClient类 ##

H5想要调用我们手机的相册和拍照，直接调用是不行的，我们必须在WebView设置中进行设置。重写WebChromeClient类。

import android.annotation.SuppressLint;
    import android.annotation.TargetApi;
    import android.app.Activity;
    import android.content.ClipData;
    import android.content.ComponentName;
    import android.content.ContentUris;
    import android.content.Context;
    import android.content.Intent;
    import android.content.pm.PackageManager;
    import android.content.pm.ResolveInfo;
    import android.database.Cursor;
    import android.graphics.Bitmap;
    import android.net.Uri;
    import android.os.Build;
    import android.os.Environment;
    import android.os.Parcelable;
    import android.provider.DocumentsContract;
    import android.provider.MediaStore;
    import android.support.v7.app.AppCompatActivity;
    import android.os.Bundle;
    import android.view.KeyEvent;
    import android.webkit.ValueCallback;
    import android.webkit.WebChromeClient;
    import android.webkit.WebSettings;
    import android.webkit.WebView;
    import android.webkit.WebViewClient;
    import android.widget.Toast;
    
    import java.io.File;
    import java.util.ArrayList;
    import java.util.List;
    
    import static android.view.KeyEvent.KEYCODE_BACK;
    
    public class SecondActivity extends Activity {
        
        private WebView webView;
        private Intent intent;
        private String url;
        /**
         * 表单的数据信息
         */
        private ValueCallback<Uri> mUploadMessage;
        private ValueCallback<Uri[]> mUploadCallbackAboveL;
        /**
         * 表单的结果回调</span>
         */
        private final static int FILECHOOSER_RESULTCODE = 1;
        private Uri imageUri;
        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_second);
            intent = getIntent();
            url = intent.getStringExtra("url");
            Toast.makeText(this, url, Toast.LENGTH_SHORT).show();
            webView = this.findViewById(R.id.webView);
    
            initWebView();
    //        this.webView.loadUrl("http://192.168.1.105:8099/photo");
            webView.loadUrl(url);
    
            webView.setWebViewClient(new WebViewClient() {
                @Override
                public boolean shouldOverrideUrlLoading(WebView view, String url) {
                    return super.shouldOverrideUrlLoading(view, url);
                }
    
                @Override
                public void onPageStarted(WebView view, String url, Bitmap favicon) {
                    super.onPageStarted(view, url, favicon);
                }
    
                @Override
                public void onPageFinished(WebView view, String url) {
                    super.onPageFinished(view, url);
                }
            });
            webView.setWebChromeClient(new OpenFileChromeClient());
        }
    
        public class OpenFileChromeClient extends WebChromeClient {
        
    
            @Override
            public boolean onShowFileChooser(WebView webView,
                                             ValueCallback<Uri[]> filePathCallback,
                                             FileChooserParams fileChooserParams) {
                mUploadCallbackAboveL = filePathCallback;
                take();
                return true;
            }
    
            /**
             * Android < 3.0 调用这个方法
             *
             * @param uploadMsg
             */
            public void openFileChooser(ValueCallback<Uri> uploadMsg) {
                mUploadMessage = uploadMsg;
                take();
            }
    
            /**
             * Android < 3.0 调用这个方法
             *
             * @param uploadMsg
             * @param acceptType
             */
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {
                mUploadMessage = uploadMsg;
                take();
            }
    
            /**
             * Android > 4.1.1 调用这个方法
             *
             * @param uploadMsg
             * @param acceptType
             * @param capture
             */
            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {
                mUploadMessage = uploadMsg;
                take();
            }
        }
    
    
        private void initWebView() {
            WebSettings setting = webView.getSettings();
            /**支持Js**/
            setting.setJavaScriptEnabled(true);
    
            /**设置自适应屏幕，两者合用**/
            //将图片调整到适合webview的大小
            setting.setUseWideViewPort(true);
            // 缩放至屏幕的大小
            setting.setLoadWithOverviewMode(true);
    
            /**缩放操作**/
            // 是否支持画面缩放，默认不支持
            setting.setBuiltInZoomControls(true);
            setting.setSupportZoom(true);
            // 是否显示缩放图标，默认显示
            setting.setDisplayZoomControls(false);
            // 设置网页内容自适应屏幕大小
            setting.setLayoutAlgorithm(WebSettings.LayoutAlgorithm.SINGLE_COLUMN);
    
            /**设置允许JS弹窗**/
            setting.setJavaScriptCanOpenWindowsAutomatically(true);
            setting.setDomStorageEnabled(true);
    
    
            /**关闭webview中缓存**/
            setting.setCacheMode(WebSettings.LOAD_NO_CACHE);
            /**设置可以访问文件 **/
            setting.setAllowFileAccess(true);
            setting.setAllowFileAccessFromFileURLs(true);
            setting.setAllowUniversalAccessFromFileURLs(true);
    
        }
    
    
        @Override
        protected void onActivityResult(int requestCode, int resultCode, Intent data) {
            super.onActivityResult(requestCode, resultCode, data);
            if (requestCode == FILECHOOSER_RESULTCODE) {
                if (null == mUploadMessage && null == mUploadCallbackAboveL) return;
                Uri result = data == null || resultCode != RESULT_OK ? null : data.getData();
                if (mUploadCallbackAboveL != null) {
                    onActivityResultAboveL(requestCode, resultCode, data);
                } else if (mUploadMessage != null) {
    
                    if (result != null) {
                        String path = getPath(getApplicationContext(),
                                result);
                        Uri uri = Uri.fromFile(new File(path));
                        mUploadMessage
                                .onReceiveValue(uri);
                    } else {
                        mUploadMessage.onReceiveValue(imageUri);
                    }
                    mUploadMessage = null;
    
    
                }
            }
        }
    
        @Override
        public boolean onKeyDown(int keyCode, KeyEvent event) {
            if ((keyCode == KEYCODE_BACK) && webView.canGoBack()) {
                webView.goBack();
                return true;
            }
            return super.onKeyDown(keyCode, event);
        }
    
        @SuppressWarnings("null")
        @TargetApi(Build.VERSION_CODES.BASE)
        private void onActivityResultAboveL(int requestCode, int resultCode, Intent data) {
            if (requestCode != FILECHOOSER_RESULTCODE
                    || mUploadCallbackAboveL == null) {
                return;
            }
    
            Uri[] results = null;
    
            if (resultCode == Activity.RESULT_OK) {
    
                if (data == null) {
    
                    results = new Uri[]{imageUri};
                } else {
                    String dataString = data.getDataString();
                    ClipData clipData = data.getClipData();
    
                    if (clipData != null) {
                        results = new Uri[clipData.getItemCount()];
                        for (int i = 0; i < clipData.getItemCount(); i++) {
                            ClipData.Item item = clipData.getItemAt(i);
                            results[i] = item.getUri();
                        }
                    }
    
                    if (dataString != null)
                        results = new Uri[]{Uri.parse(dataString)};
                }
            }
            if (results != null) {
                mUploadCallbackAboveL.onReceiveValue(results);
                mUploadCallbackAboveL = null;
            } else {
                results = new Uri[]{imageUri};
                mUploadCallbackAboveL.onReceiveValue(results);
                mUploadCallbackAboveL = null;
            }
    
            return;
        }
    
    
        private void take() {
            File imageStorageDir = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "MyApp");
            // Create the storage directory if it does not exist
            if (!imageStorageDir.exists()) {
                imageStorageDir.mkdirs();
            }
            File file = new File(imageStorageDir + File.separator + "IMG_" + String.valueOf(System.currentTimeMillis()) + ".jpg");
            imageUri = Uri.fromFile(file);
    
            final List<Intent> cameraIntents = new ArrayList<Intent>();
            final Intent captureIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
            final PackageManager packageManager = getPackageManager();
            final List<ResolveInfo> listCam = packageManager.queryIntentActivities(captureIntent, 0);
            for (ResolveInfo res : listCam) {
                final String packageName = res.activityInfo.packageName;
                final Intent i = new Intent(captureIntent);
                i.setComponent(new ComponentName(res.activityInfo.packageName, res.activityInfo.name));
                i.setPackage(packageName);
                i.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);
                cameraIntents.add(i);
    
            }
            Intent i = new Intent(Intent.ACTION_GET_CONTENT);
            i.addCategory(Intent.CATEGORY_OPENABLE);
            i.setType("image/*");
            Intent chooserIntent = Intent.createChooser(i, "Image Chooser");
            chooserIntent.putExtra(Intent.EXTRA_INITIAL_INTENTS, cameraIntents.toArray(new Parcelable[]{}));
            SecondActivity.this.startActivityForResult(chooserIntent, FILECHOOSER_RESULTCODE);
        }
    
        @SuppressLint("NewApi")
        @TargetApi(Build.VERSION_CODES.KITKAT)
        public static String getPath(final Context context, final Uri uri) {
            final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
    
            // DocumentProvider
            if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
                // ExternalStorageProvider
                if (isExternalStorageDocument(uri)) {
                    final String docId = DocumentsContract.getDocumentId(uri);
                    final String[] split = docId.split(":");
                    final String type = split[0];
    
                    if ("primary".equalsIgnoreCase(type)) {
                        return Environment.getExternalStorageDirectory() + "/" + split[1];
                    }
    
                    // TODO handle non-primary volumes
                }
                // DownloadsProvider
                else if (isDownloadsDocument(uri)) {
    
                    final String id = DocumentsContract.getDocumentId(uri);
                    final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
    
                    return getDataColumn(context, contentUri, null, null);
                }
                // MediaProvider
                else if (isMediaDocument(uri)) {
                    final String docId = DocumentsContract.getDocumentId(uri);
                    final String[] split = docId.split(":");
                    final String type = split[0];
    
                    Uri contentUri = null;
                    if ("image".equals(type)) {
                        contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
                    } else if ("video".equals(type)) {
                        contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
                    } else if ("audio".equals(type)) {
                        contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
                    }
    
                    final String selection = "_id=?";
                    final String[] selectionArgs = new String[]{split[1]};
    
                    return getDataColumn(context, contentUri, selection, selectionArgs);
                }
            }
            // MediaStore (and general)
            else if ("content".equalsIgnoreCase(uri.getScheme())) {
                return getDataColumn(context, uri, null, null);
            }
            // File
            else if ("file".equalsIgnoreCase(uri.getScheme())) {
                return uri.getPath();
            }
    
            return null;
        }
    
    
        /**
         * Get the value of the data column for this Uri. This is useful for
         * MediaStore Uris, and other file-based ContentProviders.
         *
         * @param context       The context.
         * @param uri           The Uri to query.
         * @param selection     (Optional) Filter used in the query.
         * @param selectionArgs (Optional) Selection arguments used in the query.
         * @return The value of the _data column, which is typically a file path.
         */
        public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
            Cursor cursor = null;
            final String column = "_data";
            final String[] projection = {column};
    
            try {
                cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
                if (cursor != null && cursor.moveToFirst()) {
                    final int column_index = cursor.getColumnIndexOrThrow(column);
                    return cursor.getString(column_index);
                }
            } finally {
                if (cursor != null) cursor.close();
            }
            return null;
        }
    
    
        /**
         * @param uri The Uri to check.
         * @return Whether the Uri authority is ExternalStorageProvider.
         */
        public static boolean isExternalStorageDocument(Uri uri) {
            return "com.android.externalstorage.documents".equals(uri.getAuthority());
        }
    
    
        /**
         * @param uri The Uri to check.
         * @return Whether the Uri authority is DownloadsProvider.
         */
        public static boolean isDownloadsDocument(Uri uri) {
            return "com.android.providers.downloads.documents".equals(uri.getAuthority());
        }
    
    
        /**
         * @param uri The Uri to check.
         * @return Whether the Uri authority is MediaProvider.
         */
        public static boolean isMediaDocument(Uri uri) {
            return "com.android.providers.media.documents".equals(uri.getAuthority());
        }
    }

**完整代码下载地址：[下载地址][Link 1]**

[Android _H5_React-Native]: https://blog.csdn.net/To_be_Designer/article/details/79891496
[Android _WebView]: https://blog.csdn.net/to_be_designer/article/details/48397789
[Link 1]: https://download.csdn.net/download/to_be_designer/10343940