场景：有时使用后台给的H5或者第三方SDK比如蚂蚁智能客服，当用webview去加载所给的H5中有上传本地文件时，点击上传按钮无反应。

我用的是github上开源的AgentWeb（也可直接使用WebView）

AgentVIew的用法很简单，这里就不赘述了。

关键点：

1、给WebVIew设置WebChromeClient时注意实现以下几个方法

private ValueCallback<Uri> mUploadMessage;
private ValueCallback<Uri[]> mUploadCallbackAboveL;
private int FILE_CHOOSER_RESULT_CODE = 200;    

private com.just.agentweb.WebChromeClient mWebViewClient = new com.just.agentweb.WebChromeClient() {

        // For Android < 3.0
        public void openFileChooser(ValueCallback<Uri> valueCallback) {
            mUploadMessage = valueCallback;
            // 检查权限
            checkPermission();
        }

        // For Android  >= 3.0
        public void openFileChooser(ValueCallback valueCallback, String acceptType) {
            mUploadMessage = valueCallback;
            checkPermission();
        }

        //For Android  >= 4.1
        public void openFileChooser(ValueCallback<Uri> valueCallback, String acceptType, String capture) {
            mUploadMessage = valueCallback;
            checkPermission();
        }

        // For Android >= 5.0
        @Override
        public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathCallback, WebChromeClient.FileChooserParams fileChooserParams) {
            mUploadCallbackAboveL = filePathCallback;
            checkPermission();
            return true;
        }

    };

2、在onActivityResult做判断

    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        super.onActivityResult(requestCode, resultCode, data);
        if (requestCode == FILE_CHOOSER_RESULT_CODE) {
            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) {
                mUploadMessage.onReceiveValue(result);
                mUploadMessage = null;
            }
        }
    }


    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    private void onActivityResultAboveL(int requestCode, int resultCode, Intent intent) {
        if (requestCode != FILE_CHOOSER_RESULT_CODE || mUploadCallbackAboveL == null)
            return;
        Uri[] results = null;
        if (resultCode == Activity.RESULT_OK) {
            if (intent != null) {
                String dataString = intent.getDataString();
                ClipData clipData = intent.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)};
            }
        }
        mUploadCallbackAboveL.onReceiveValue(results);
        mUploadCallbackAboveL = null;
    }

3、注意检查权限

    // 相册照片读取权限检查
    private void checkPermission() { // 权限检查
        checkPermission(Manifest.permission.READ_EXTERNAL_STORAGE, null,
                this::openImageChooserActivity, null);
    }

这样WebView就能正常调起文件选择了