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