WebChromeClient中操作

重写openFileChooser(5.0以下)
重写onShowFileChooser(5.0以上)

    public void openFileChooser(ValueCallback<Uri> filePathsCallback) {
        this.openFileChooser(filePathsCallback, "*/*");
    }
    
    public void openFileChooser( ValueCallback<Uri> filePathsCallback, String acceptType ) {
        this.openFileChooser(filePathsCallback, acceptType, null);
    }

    //@Override
    public void openFileChooser(ValueCallback<Uri> filePathsCallback, String acceptType, String capture) {
        this.filePathsCallback = filePathsCallback;
        showFileChooserDialog(acceptType.contains("video") ? MediaStore.ACTION_VIDEO_CAPTURE : MediaStore.ACTION_IMAGE_CAPTURE);
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    @Override
    public boolean onShowFileChooser(WebView webView, ValueCallback<Uri[]> filePathsCallbacks, final FileChooserParams fileChooserParams) {
        this.filePathsCallbacks = filePathsCallbacks;
        boolean hasVideo = false;
        for (String acceptType : fileChooserParams.getAcceptTypes()) {
            if (acceptType.contains("video")) hasVideo = true;
        }
        showFileChooserDialog(hasVideo ? MediaStore.ACTION_VIDEO_CAPTURE : MediaStore.ACTION_IMAGE_CAPTURE);
        return true;
    }

    /**
     * 根据类型打开不同的界面
     * @param type 类型
     */
    private void showFileChooserDialog(String type){
        Intent intent = new Intent();
        intent.setAction(type);
        intent.addCategory(Intent.CATEGORY_DEFAULT);
        FileUtils.deleteFile(new File(systemCameraPicPath));
        intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(new File(systemCameraPicPath)));
        curActivity.startActivityForResult(intent, 308);
    }

onActivityResult回调

    if (null == myCameraWebChromeClient.getFilePathsCallback() && null == myCameraWebChromeClient.getFilePathsCallbacks()) return;
    Uri result = intent == null || resultCode != RESULT_OK ? null : intent.getData();
    if (myCameraWebChromeClient.getFilePathsCallbacks() != null) { // 5.0 以上
        onActivityResultAboveL(requestCode, resultCode, intent);
    } else if (myCameraWebChromeClient.getFilePathsCallback() != null) { // 5.0 以下
        myCameraWebChromeClient.getFilePathsCallback().onReceiveValue(result);
        myCameraWebChromeClient.setFilePathsCallback(null);
    }

Android 5.0以下

    myCameraWebChromeClient.getFilePathsCallback().onReceiveValue(result);
    myCameraWebChromeClient.setFilePathsCallback(null);

Android 5.0以上onActivityResult回调

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    private void onActivityResultAboveL(int requestCode, int resultCode, Intent data) {
        Uri[] results = null;
        if (resultCode == RESULT_OK) {
            if (data == null) {
            } else {
                String dataString = data.getDataString();
                ClipData clipData = data.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)};
            }
        }
        myCameraWebChromeClient.getFilePathsCallbacks().onReceiveValue(results);
        myCameraWebChromeClient.setFilePathsCallbacks(null);
    }