职场小白迷上优美句子:
推迟,拖延真的是件可怕的事,过去了好久还是原来的样子。
公司现在的项目中有一个需求,需要把本地 json 格式的数据导入到项目中使用,其实简单的逻辑就是:使用安卓隐式跳转的方式进入到文件管理器,然后寻找需要的文件,点击文件之后返回该文件的路径,之后根据路径获取到该文件并对其进行相应的操作。
这些代码不是自己在Android 官网上找的,也是从百度搜的,当然需要标明出处:
Android调用系统自带的文件管理器,打开指定路径_android file 内置文件到机器特定路径_沧海龙腾LV的博客-CSDN博客
1.进入文件管理器
- private void intoFileManager() {
- Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
- intent.setType("*/*");//无类型限制
- // 有类型限制是这样的:
- // intent.setType(“image/*”);//选择图片
- // intent.setType(“audio/*”); //选择音频
- // intent.setType(“video/*”); //选择视频 (mp4 3gp 是android支持的视频格式)
- // intent.setType(“video/*;image/*”);//同时选择视频和图片
-
- intent.addCategory(Intent.CATEGORY_OPENABLE);
- startActivityForResult(intent, 1);
- }
2.返回结果
- String path;
- @Override
- protected void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
- super.onActivityResult(requestCode, resultCode, data);
-
- if (resultCode == Activity.RESULT_OK) {
- Uri uri = data.getData();
- if ("file".equalsIgnoreCase(uri.getScheme())){//使用第三方应用打开
- path = uri.getPath();
- mFilePathTv.setText(path);
- Log.d("queryfilepath", "返回结果1: " + path);
- return;
- }
- if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {//4.4以后
- path = FileChooseUtil.getPath(this, uri);
- mFilePathTv.setText(path);
- Log.d("queryfilepath", "返回结果2: " + path);
-
- } else {//4.4以下下系统调用方法
- path = FileChooseUtil.getRealPathFromURI(uri);
- mFilePathTv.setText(path);
- Log.d("queryfilepath", "返回结果3: " + path);
-
- }
- }
-
- }
3.用到的工具类
- public class FileChooseUtil {
-
- private static Context context;
- private static FileChooseUtil util = null;
-
- private FileChooseUtil(Context context) {
- this.context = context;
- }
-
- public static FileChooseUtil getInstance(Context context) {
- if (util == null) {
- util = new FileChooseUtil(context);
- }
- return util;
- }
-
- /**
- * 对外接口 获取uri对应的路径
- *
- * @param uri
- * @return
- */
- public String getChooseFileResultPath(Uri uri) {
- String chooseFilePath = null;
- if ("file".equalsIgnoreCase(uri.getScheme())) {//使用第三方应用打开
- chooseFilePath = uri.getPath();
- Toast.makeText(context, chooseFilePath, Toast.LENGTH_SHORT).show();
- return chooseFilePath;
- }
- if (Build.VERSION.SDK_INT > Build.VERSION_CODES.KITKAT) {//4.4以后
- chooseFilePath = getPath(context, uri);
- } else {//4.4以下下系统调用方法
- chooseFilePath = getRealPathFromURI(uri);
- }
- return chooseFilePath;
- }
-
- public static String getRealPathFromURI(Uri contentUri) {
- String res = null;
- String[] proj = {MediaStore.Images.Media.DATA};
- Cursor cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
- if (null != cursor && cursor.moveToFirst()) {
- int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
- res = cursor.getString(column_index);
- cursor.close();
- }
- return res;
- }
-
- /**
- * 专为Android4.4设计的从Uri获取文件绝对路径,以前的方法已不好使
- */
- @SuppressLint("NewApi")
- public static String getPath(final Context context, final Uri uri) {
-
- final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
-
- // DocumentProvider
- if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
- // ExternalStorageProvider
- if (isExternalStorageDocument(uri)) {
- final String docId = DocumentsContract.getDocumentId(uri);
- final String[] split = docId.split(":");
- final String type = split[0];
-
- if ("primary".equalsIgnoreCase(type)) {
- return Environment.getExternalStorageDirectory() + "/" + split[1];
-
- }
- }
- // DownloadsProvider
- else if (isDownloadsDocument(uri)) {
- final String id = DocumentsContract.getDocumentId(uri);
- final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
- return getDataColumn(context, contentUri, null, null);
-
- }
- // MediaProvider
- else if (isMediaDocument(uri)) {
- final String docId = DocumentsContract.getDocumentId(uri);
- final String[] split = docId.split(":");
- final String type = split[0];
-
- Uri contentUri = null;
- if ("image".equals(type)) {
- contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
-
- } else if ("video".equals(type)) {
- contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
-
- } else if ("audio".equals(type)) {
- contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
-
- }
-
- final String selection = "_id=?";
- final String[] selectionArgs = new String[]{split[1]};
-
- return getDataColumn(context, contentUri, selection, selectionArgs);
-
- }
-
- }
- // MediaStore (and general)
- else if ("content".equalsIgnoreCase(uri.getScheme())) {
- return getDataColumn(context, uri, null, null);
-
- }
- // File
- else if ("file".equalsIgnoreCase(uri.getScheme())) {
- uri.getPath();
-
- }
- return null;
- }
-
- private static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
- Cursor cursor = null;
- final String column = "_data";
- final String[] projection = {column};
- try {
- cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs,
- null);
- if (cursor != null && cursor.moveToFirst()) {
- final int column_index = cursor.getColumnIndexOrThrow(column);
- return cursor.getString(column_index);
- }
- } finally {
- if (cursor != null)
- cursor.close();
- }
- return null;
- }
-
- /**
- * @param uri The Uri to check.
- * @return Whether the Uri authority is ExternalStorageProvider.
- */
- private static boolean isExternalStorageDocument(Uri uri) {
- return "com.android.externalstorage.documents".equals(uri.getAuthority());
- }
-
- /**
- * @param uri The Uri to check.
- * @return Whether the Uri authority is DownloadsProvider.
- */
- private static boolean isDownloadsDocument(Uri uri) {
- return "com.android.providers.downloads.documents".equals(uri.getAuthority());
- }
-
- /**
- * @param uri The Uri to check.
- * @return Whether the Uri authority is MediaProvider.
- */
- private static boolean isMediaDocument(Uri uri) {
- return "com.android.providers.media.documents".equals(uri.getAuthority());
- }
- }
注意:记得开启手机的读写权限,不然会报权限拒绝异常:SecurityException ! ! !