我使用以下代码改进了解决方案：
// Validation utility for mime types private List<String> extractValidMimeTypes(String[] mimeTypes) { List<String> results = new ArrayList<String>(); List<String> mimes; if (mimeTypes.length() == 1 && mimeTypes[0].contains(",")) { mimes = Arrays.asList(mimeTypes[0].split(",")); } else { mimes = Arrays.asList(mimeTypes); } MimeTypeMap mtm = MimeTypeMap.getSingleton(); for (String mime : mimes) { if (mime != null && mime.trim().startsWith(".")) { String extensionWithoutDot = mime.trim().substring(1, mime.trim().length()); String derivedMime = mtm.getMimeTypeFromExtension(extensionWithoutDot); if (derivedMime != null && !results.contains(derivedMime)) { // adds valid mime type derived from the file extension results.add(derivedMime); } } else if (mtm.getExtensionFromMimeType(mime) != null && !results.contains(mime)) { // adds valid mime type checked agains file extensions mappings results.add(mime); } } return results; }public boolean onShowFileChooser(WebView webView, final ValueCallback<Uri[]> filePathsCallback, final WebChromeClient.FileChooserParams fileChooserParams) { Intent intent = fileChooserParams.createIntent(); List<String> validMimeTypes = extractValidMimeTypes(fileChooserParams.getAcceptTypes()); if (validMimeTypes.isEmpty()) { intent.setType(DEFAULT_MIME_TYPE); } else { intent.setType(String.join(" ", validMimeTypes)); } ...有关更多详细信息，请参见我的请求请求。
