android_WebView

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WebView 增加横向进度条

progressBar = new ProgressBar(getContext(), null, android.R.attr.progressBarStyleHorizontal);

progressBar.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, 5, 0, 0));

addView(progressBar);

WebView 设置属性

WebSettings ws = this.getSettings();

ws.setJavaScriptEnabled(true);//允许javascript

ws.setAllowFileAccess(true);启用或禁用WebView访问文件数据

ws.setBuiltInZoomControls(false);设置是否支持缩放

ws.setSupportZoom(true);设置是否支持变焦

ws.setDomStorageEnabled(true);

ws.setLayoutAlgorithm(LayoutAlgorithm.NARROW_COLUMNS);设置布局方式

ws.setUserAgentString("");

setWebViewClient()

@Override

public boolean shouldOverrideUrlLoading(WebView view, String url) {

//覆盖loadUrl方法，默认以浏览器打开URL

}

@Override

public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) {

//失败回调

view.loadUrl("file:///android_asset/error.html");

}

setWebChromeClient()

@Override

public void onProgressChanged(WebView view, int newProgress) {

if (newProgress == 100) {//加载进度条

progressBar.setVisibility(GONE);

} else {

if (progressBar.getVisibility() == GONE) {

progressBar.setVisibility(VISIBLE);

}

progressBar.setProgress(newProgress);

}

网页弹出框重写

public boolean onJsAlert()

onJsConfirm()

onJsPrompt()

//响应网页File标签，现实图片上传

// 3.0 + 调用这个方法

public void openFileChooser(ValueCallback<Uri> uploadMsg,String acceptType) {

mUploadMessage = uploadMsg;//mUploadMessage 全局变量

//跳转系统相册

Intent intent = new Intent(Intent.ACTION_PICK);

intent.setType("image/*");// 相片类型

BaseActivity.currentActivity().startActivityForResult(intent, WebViewActivity.FILECHOOSER_RESULTCODE);

//跳转系统相机

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

BaseActivity.currentActivity().startActivityForResult(intent,

WebViewActivity.FILECHOOSER_RESULTCODE);

}

// For Android > 4.1.1

public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType, String capture) {

openFileChooser(uploadMsg, acceptType);

}

// Android < 3.0 调用这个方法

public void openFileChooser(ValueCallback<Uri> uploadMsg) {

openFileChooser(uploadMsg, "");

}

javascript调用本地方法

this.addJavascriptInterface(new JSAndroidBridge(this), "android");

执行JS方法，可通过参数向JS当前页面传值

public void executeJSMethod(String methodName, String param) {

this.superLoadUrl("javascript:" + methodName + "('" + param + "')");

}

可供JS调用的类

public final class JSAndroidBridge {

private JSBridgeWebView webView;

public JSAndroidBridge(JSBridgeWebView webView) {

super();

this.webView = webView;

}

@JavascriptInterface

public void refreshHomeActivityList() {//js可以通过方法名调用此方法

//do something

}

图片上传

1.实现上面提到的openFileChooser(部分Android4.4.2不响应此方法)

2.当前场景中onActivityResult中获取URI

3.uri不为空是从相册获取的图片，为空是从相机获得图片

4.部分相机获取的图片是缩略图

5.部分手机从系统获取的图片是横向

@Override

protected void onActivityResult(int requestCode, int resultCode, Intent intent) {

if (requestCode == FILECHOOSER_RESULTCODE) {

mUploadMessage = .getWebView().getmUploadMessage();

if (null == mUploadMessage)

return;

Uri uri = intent == null || resultCode != RESULT_OK ? null : intent.getData();

}

mUploadMessage.onReceiveValue(uri);//关键代码

}

图片上传过程中得问题及解决方案

Android4.4.2 不响应openFileChooser方法

上面设置的setUserAgentString()方法中将当前系统版本传到页面，页面判断为4.4.2系统不使用File标签上传图片，改为本地调用上传图片方法，上传成功后返回的图片路径，调用js的方法通知页面图片上传成功

选取图片操作bitmap， OOM

BitmapFactory.Options opt = new BitmapFactory.Options();

opt.inJustDecodeBounds = true;//只获取图片参数

BitmapFactory.decodeFile(img_path, opt);

if (opt.outWidth > 1000 || opt.outHeight > 1000) {

opt.inSampleSize = 5;//缩小1/5

}

opt.inJustDecodeBounds = false;

Bitmap bitmap = BitmapFactory.decodeFile(img_path, opt);

判断图片的方向

//获取图片的路径

private String getImgPath(Uri uri){

String img_path = "";

if(uri != null){

String[] proj = { MediaStore.Images.Media.DATA };

Cursor actualimagecursor = managedQuery(uri,proj,null,null,null);

int actual_image_column_index = actualimagecursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);

actualimagecursor.moveToFirst();

img_path = actualimagecursor.getString(actual_image_column_index);

}

return img_path;

}

//获取图片的存储角度

private int getBitmapDegree(String path) {

int degree = 0;

try {

// 从指定路径下读取图片，并获取其EXIF信息

ExifInterface exifInterface = new ExifInterface(path);

// 获取图片的旋转信息

int orientation = exifInterface.getAttributeInt(ExifInterface.TAG_ORIENTATION,

ExifInterface.ORIENTATION_NORMAL);

switch (orientation) {

case ExifInterface.ORIENTATION_ROTATE_90:

degree = 90;

break;

case ExifInterface.ORIENTATION_ROTATE_180:

degree = 180;

break;

case ExifInterface.ORIENTATION_ROTATE_270:

degree = 270;

break;

}

} catch (IOException e) {

e.printStackTrace();

}

return degree;

}

//旋转图片

public Bitmap rotateBitmapByDegree(Bitmap bm, int degree) {

Bitmap returnBm = null;

// 根据旋转角度，生成旋转矩阵

Matrix matrix = new Matrix();

matrix.postRotate(degree);

try {

// 将原始图片按照旋转矩阵进行旋转，并得到新的图片

returnBm = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);

} catch (OutOfMemoryError e) {

}

if (returnBm == null) {

returnBm = bm;

}

if (bm != returnBm) {

bm.recycle();

}

return returnBm;

}

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