android webview js交互 调取本地相册（兼容各个版本）并且上传到服务器端。

       android webview  js交互，调取本地相册，并且实现上传。

      

     首先我们要理解整个互动过程，在网页webview的的组件是 input输入框，输入类型为file,点击-----> 调用安卓不同的版本

onShowFileChooser（5.0专用的方法，是隐性的），
openFileChooser（3.0,4.0）这些都要写进去，是为了针对不同的安卓版本。
----->启动android系统自带的相册选择 ---->选择完成之后，回调 onActivityResult，这个方法很重要，里面有针对不同安卓版本的处理，特别是5.0 ，返回来的是一个URI数组，需要进行处理。废话不说上代码：
   
webView.setWebChromeClient(new WebChromeClient() {            @Override            public boolean onJsAlert(WebView view, String url, String message, final JsResult result) {                AlertDialog.Builder b2 = new AlertDialog.Builder(WebViewActivity.this)                        .setTitle("友情提示：").setMessage(message)                        .setPositiveButton("ok",                                new AlertDialog.OnClickListener() {                                    @Override                                    public void onClick(DialogInterface dialog,                                                        int which) {                                        result.confirm();                                        // MyWebView.this.finish();                                    }                                });                b2.setCancelable(false);                b2.create();                b2.show();                return true;            }            @Override            public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, FileChooserParams fileChooserParams) {                umUploadMessages = filePathCallback;                mfileChooserParams = fileChooserParams;                Intent i = new Intent(Intent.ACTION_GET_CONTENT);                i.addCategory(Intent.CATEGORY_OPENABLE);                i.putExtra("return-data", true);                i.setType("image/*");                i.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,                        "image/*");                startActivityForResult(Intent.createChooser(i, "选择相册"),                        FILECHOOSER_RESULTCODE_5);                return true;            }            // For Android 3.0            public void openFileChooser(ValueCallback<Uri> uploadMsg) {                mUploadMessage = uploadMsg;                Intent i = new Intent(Intent.ACTION_GET_CONTENT);                i.addCategory(Intent.CATEGORY_OPENABLE);                i.putExtra("return-data", true);                i.setType("image/*");                i.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,                        "image/*");                startActivityForResult(Intent.createChooser(i, "选择相册"),                        FILECHOOSER_RESULTCODE);            }            // For Android > 4.1            public void openFileChooser(ValueCallback<Uri> uploadMsg,                                        String acceptType, String capture) {                Toast.makeText(WebViewActivity.this,"你大爷的",Toast.LENGTH_SHORT).show();                mUploadMessage = uploadMsg;                Intent i = new Intent(Intent.ACTION_GET_CONTENT);                i.addCategory(Intent.CATEGORY_OPENABLE);                i.putExtra("return-data", true);                i.setType("image/*");                i.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,                        "image/*");                startActivityForResult(Intent.createChooser(i, "选择相册"),                        FILECHOOSER_RESULTCODE);            }            // Andorid 3.0 +            public void openFileChooser(ValueCallback<Uri> uploadMsg, String acceptType) {                 mUploadMessage = uploadMsg;                Intent i = new Intent(Intent.ACTION_GET_CONTENT);                i.addCategory(Intent.CATEGORY_OPENABLE);                i.putExtra("return-data", true);                i.setType("image/*");                i.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,                        "image/*");                startActivityForResult(Intent.createChooser(i, "选择相册"),                        FILECHOOSER_RESULTCODE);            }        });
回调处理：
  

 /**     * 取照片完成之后的回选调     */    @Override    protected void onActivityResult(int requestCode, int resultCode, Intent data) {        super.onActivityResult(requestCode, resultCode, data);        if (requestCode == FILECHOOSER_RESULTCODE) {            if (null == mUploadMessage) return;            if (null == data){                mUploadMessage.onReceiveValue(null);                mUploadMessage = null;            }else{                Uri result = data == null || resultCode != RESULT_OK ? null                        : data.getData();                mUploadMessage.onReceiveValue(result);                mUploadMessage = null;            }        }else  if (requestCode == FILECHOOSER_RESULTCODE_5){// 5.0适配，主要是因为5.0的返回参数不同。            // 处理5.0的callback            if (umUploadMessages != null) {                if (null != data) {
// 5.0的处理方式不同，要注意。                    ArrayList<String> resultList = data                            .getStringArrayListExtra("data");                    umUploadMessages.onReceiveValue(                            mfileChooserParams.parseResult(resultCode, data));                    umUploadMessages = null;                } else {                    umUploadMessages.onReceiveValue(null);                }            }        }    }