在Android浏览器中通过WebView调用相机拍照/选择文件 上传到服务器

最近做的一个项目中，有这样一个要求，在浏览器中调用系统的拍照功能或者选择文件，然后将文件上传到服务器，类似修改头像。        简单而言，就是在一个html页面中有这样一段代码 <input class="filePrew" type="file" capture="camera" accept="image/*" name="image">

刚开始的时候，没有感觉很难的，因为在UC浏览器、系统自带的浏览器中都可以进行拍照/文件管理器选择，可是在自己所写的Activity中却不行。后来实在是没有思路了，就在网上找了一下，发现要        实现这种功能，都是在webview的WebChromeClient中覆盖掉openFileChooser方法，注意openFileChooser方法在WebChromeClient中有@hide标记。这里只管重写即可,下面将主要代码贴出来，做个记录        

private ValueCallback<Uri> mUploadFile;
    /**拍照/选择文件请求码*/
    private static final int REQUEST_UPLOAD_FILE_CODE = 12343;
    private void setWebChromeClient()
    {
        if (null != mMainWebView)
        {
            mMainWebView.setWebChromeClient(new WebChromeClient()
            {
                // Andorid 4.1+
                public void openFileChooser(ValueCallback<Uri> uploadFile, String acceptType, String capture)
                {
                    openFileChooser(uploadFile);
                }

                // Andorid 3.0 +
                public void openFileChooser(ValueCallback<Uri> uploadFile, String acceptType)
                {
                    openFileChooser(uploadFile);
                }

                // Android 3.0
                public void openFileChooser(ValueCallback<Uri> uploadFile)
                {
                    // Toast.makeText(WebviewActivity.this, "上传文件/图片",Toast.LENGTH_SHORT).show();
                    mUploadFile = uploadFile;
                    startActivityForResult(Intent.createChooser(createCameraIntent(), "Image Browser"), REQUEST_UPLOAD_FILE_CODE);
                }
            });
        }
    }

    private Intent createCameraIntent()
    {
        Intent cameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);//拍照
        //=======================================================
        Intent imageIntent = new Intent(Intent.ACTION_GET_CONTENT);//选择图片文件
        imageIntent.setType("image/*");
        //=======================================================
        return cameraIntent;
    }
    //最后在OnActivityResult中接受返回的结果
    protected void onActivityResult(int requestCode, int resultCode, Intent data)
    {
        if (requestCode == REQUEST_UPLOAD_FILE_CODE && resultCode == RESULT_OK)
        {
            if (null == mUploadFile)
            {
                return;
            }
            Uri result = (null == data) ? null : data.getData();
            if (null != result)
            {
                ContentResolver resolver = this.getContentResolver();
                String[] columns = { MediaStore.Images.Media.DATA };
                Cursor cursor = resolver.query(result, columns, null, null, null);
                cursor.moveToFirst();
                int columnIndex = cursor.getColumnIndex(columns[0]);
                String imgPath = cursor.getString(columnIndex);
                System.out.println("imgPath = " + imgPath);
                if (null == imgPath)
                {
                    return;
                }
                File file = new File(imgPath);
                   //将图片处理成大小符合要求的文件
                result = Uri.fromFile(handleFile(file));
                mUploadFile.onReceiveValue(result);
                mUploadFile = null;
            }
        }
        super.onActivityResult(requestCode, resultCode, data);
    }
    /**处理拍照/选择的文件*/
    private File handleFile(File file)
    {
        DisplayMetrics dMetrics = getResources().getDisplayMetrics();
        BitmapFactory.Options options = new Options();
        options.inJustDecodeBounds = true;
         BitmapFactory.decodeFile(file.getAbsolutePath(), options);
        int imageWidth = options.outWidth;
        int imageHeight = options.outHeight;
        System.out.println("  imageWidth = " + imageWidth + " imageHeight = " + imageHeight);
        int widthSample = (int) (imageWidth / (dMetrics.density * 90));
        int heightSample = (int) (imageHeight / (dMetrics.density * 90));
        System.out.println("widthSample = " + widthSample + " heightSample = " + heightSample);
        options.inSampleSize = widthSample < heightSample ? heightSample : widthSample;
        options.inJustDecodeBounds = false;
        Bitmap newBitmap = BitmapFactory.decodeFile(file.getAbsolutePath(), options);
        System.out.println("newBitmap.size = " + newBitmap.getRowBytes() * newBitmap.getHeight());
        File handleFile = new File(file.getParentFile(), "upload.png");
        try
        {
            if (newBitmap.compress(CompressFormat.PNG, 50, new FileOutputStream(handleFile)))
            {
                System.out.println("保存图片成功");
            }
        }
        catch (FileNotFoundException e)
        {
            e.printStackTrace();
        }

        return handleFile;

    }

  这样就可以在WebView中上传文件了。记得要添加相应的权限！  
       参考：http://developer.android.com/about/versions/android-3.0.html

  http://blog.sina.com.cn/s/blog_5749ead90101clrn.html