前情描述：
使用系统文件管理器，选择指定文件类型上传。
基础知识
- MIME
- 调起文件管理器
- 指定浏览位置(路径转URI)
- 设置多种文件类型
- URI转路径
1. MIME
MIME (Multipurpose Internet Mail Extensions) 是描述消息内容类型的因特网标准。
final String DOC = "application/msword"; final String XLS = "application/vnd.ms-excel"; final String PPT = "application/vnd.ms-powerpoint"; final String DOCX = "application/vnd.openxmlformats-officedocument.wordprocessingml.document"; final String XLSX = "application/x-excel"; final String XLSX = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet"; final String PPTX = "application/vnd.openxmlformats-officedocument.presentationml.presentation"; final String PDF = "application/pdf"; final String MP4 = "video/mp4"; final String M3U8 = "application/x-mpegURL"; ... 更多文件类型，自行百度文件类型
2. 调起文件管理器
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
//任意类型文件
intent.setType("*/*");
intent.addCategory(Intent.CATEGORY_OPENABLE);
startActivityForResult(intent,1);
//-------常用类型
//图片
//intent.setType(“image/*”);
//音频
//intent.setType(“audio/*”);
//视频
//intent.setType(“video/*”);
//intent.setType(“video/*;image/*”);
1.所有类型文件
Intent intent= new Intent(Intent.ACTION_PICK, null); intent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*"); startActivityForResult(intent, REQUEST_CODE_FILE);2.系统的相冊
@Override
public void initData() {
// 请求文件选择权限
if (ContextCompat.checkSelfPermission(getContext(), android.Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(getActivity(), new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE}, REQUEST_FILE);
} else {
initUpload(); // 如果权限已授予，直接开始选择文件
}
}
private void initUpload() {
// 创建一个ActivityResultLauncher来处理返回的结果
ActivityResultLauncher launcher = registerForActivityResult(new ActivityResultContracts.StartActivityForResult(), result -> {
// 在这里可以执行上传附件的操作
if (result.getResultCode() == Activity.RESULT_OK) {
viewModel.fileUploadByPath(result.getData().getData());
}
});
binding.btUpload.setOnClickListener(view -> openFilePicker(launcher));
}
private void openFilePicker(ActivityResultLauncher launcher) {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.setType("*/*");//"image/*":可以指定MIME类型，这里以选择图片为例
// 启动文件选择器
launcher.launch(intent);
}
示例
3. 指定浏览位置(路径转URI)
跳转到指定路径下，涉及到将路径转为URI，考虑Android版本区别
/**
* file --> uri
* @param context
* @param file
*
* @return
*/
public static Uri getUriFromFile(Context context, File file) {
if (context == null || file == null) {
throw new NullPointerException();
}
Uri uri;
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
uri = FileProvider.getUriForFile(context.getApplicationContext(), BuildConfig.APPLICATION_ID + ".fileprovider", file);
} else {
uri = Uri.fromFile(file);
}
return uri;
}
getUriFromFile
由于7.0的升级还需要在AndroidManifest.xml中配置FileProvider
<provider
android:name="android.support.v4.content.FileProvider"
android:authorities="${applicationId}.fileprovider"
android:exported="false"
android:grantUriPermissions="true">
<meta-data
android:name="android.support.FILE_PROVIDER_PATHS"
android:resource="@xml/file_paths" />
</provider>
FileProvider
${applicationId}.fileprovider这个配置要记牢，后期遇到大坑就靠这个值了。
xml/file_paths 文件如下: 参考CSDN
<!--物理路径相当于Context.getFilesDir() + /path/--> <files-path name="name" path="path" /> <!--物理路径相当于Context.getCacheDir() + /path/--> <cache-path name="name" path="path" /> <!-- 物理路径相当于Environment.getExternalStorageDirectory() + /path/--> <external-path name="name" path="path" /> <!-- 物理路径相当于Context.getExternalFilesDir(String) + /path/--> <external-files-path name="name" path="path" /> <!-- 物理路径相当于Context.getExternalCacheDir() + /path/--> <external-cache-path name="name" path="path" />file_paths
将文件路径转(使用微信下载目录做测试)为URI后，设置到Intent中。
/**
* 根据类型，加载文件选择器
*/
private void chooseFileWithPath() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
//跳转指定路径，如果路径不存在，切到sdcard
//需要读权限
String path = getSDPath();
if (!TextUtils.isEmpty(path)) {
//使用微信下载目录测试
path = path + File.separator + "tencent/MicroMsg/Download";
File file = new File(path);
if (file.exists()) {
//主要代码
intent.setDataAndType(FileUtil.getUriFromFile(this, new File(path)), "*/*");
} else {
intent.setType("*/*");
}
} else {
intent.setType("*/*");
}
startActivityForResult(intent, REQUEST_CODE_FILE);
}
根据类型，加载文件选择器
主要生效代码：
Intent intent = new Intent(action,uri);
intent.setType("*/*");
startActivityForResult(intent, REQUEST_CODE_FILE);
或者
Intent intent = new Intent(action); intent.setDataAndType(uri, "*/*"); startActivityForResult(intent, REQUEST_CODE_FILE);特别注意：
指定目录这种方式调起，在原生的管理器没有其他注意的，但是如果用户使用三方的管理器，例如QQ浏览器，那么在进入到指定目录下，不可以执行返回操作。
例如：
如果路径设置的是
/sdcard/tencent/MicroMsg/Download，在进入download目录下，如果该目录下没有文件，那么想返回到其上层目录MicroMsg，是不可以的。
4. 设置多种文件类型
通过intent.setType()方式设置的文件类型，只能生效一次，所以如果想只选择doc、excel、pdt、ppt等办公文档，过滤掉其他文件，就不能使用intent .setType()方式，而是使用Intent.EXTRA_MIME_TYPES来传值。
final String DOC = "application/msword";
final String XLS = "application/vnd.ms-excel";
final String PPT = "application/vnd.ms-powerpoint";
final String DOCX = "application/vnd.openxmlformats-officedocument.wordprocessingml.document";
final String XLSX = "application/x-excel";
final String XLSX = "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet";
final String PPTX = "application/vnd.openxmlformats-officedocument.presentationml.presentation";
final String PDF = "application/pdf";
/**
* 多种文件类型
*/
private void chooseMoreTypes() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
String[] mimeTypes = {DOC, DOCX, PDF, PPT, PPTX, XLS, XLS1, XLSX};
intent.setType("application/*");
intent.putExtra(Intent.EXTRA_MIME_TYPES, mimeTypes);
startActivityForResult(intent, REQUEST_CODE_FILE);
}
多种文件类型
以上是准备工作，调起文件管理器进行选择文件，对于一个Android开发者来说，以上步骤只是相当于一小步，不要忘记适配。
接下来才是长征路。
5. URI转路径
在这一步主要解决的是将返回的URI转换为File，大坑也往往就在这一步出现。
问题1:Android 7.0以上获取文件地址，报错 column ‘_data’ does not exist. Available columns: [] 问题2:在DocumentProvider中我在调试的过程发现有些文件路径不是primary而是以home开头的路径 content://com.android.externalstorage.documents/document/home:A20220419194337xzspj_chenxiaobin.docx 问题3：在DownloadsProvider中uri路径中返回的不是content://com.android.providers.downloads.documents/document/158 这种常规类型的 地址而是返回的是:content://com.android.providers.downloads.documents/document/raw:/storage/emulated/0/Download/Browser/12345_1.0.apk 。。。问题
上代码
1 import android.annotation.SuppressLint;
2 import android.content.ContentResolver;
3 import android.content.ContentUris;
4 import android.content.Context;
5 import android.content.CursorLoader;
6 import android.database.Cursor;
7 import android.net.Uri;
8 import android.os.Build;
9 import android.os.Environment;
10 import android.provider.DocumentsContract;
11 import android.provider.MediaStore;
12 import android.text.TextUtils;
13 import android.util.Log;
14
15 import java.io.File;
16 import java.io.InputStream;
17 import java.util.Locale;
18
19 import cn.hutool.core.io.FileUtil;
20
21 public class FileUtils {
22
23 /**
24 * 根据Uri获取文件绝对路径
25 *
26 * @param context
27 * @param fileUri
28 * @return
29 */
30 public static String getPath(Context context, Uri fileUri) {
31 if (context == null || fileUri == null) {
32 return null;
33 }
34 String realPath;
35 // SDK < API11
36 if (Build.VERSION.SDK_INT < 11) {
37 realPath = FileUtils.getRealPathFromURI_BelowAPI11(context, fileUri);
38 }
39 // SDK >= 11 && SDK < 19
40 else if (Build.VERSION.SDK_INT < 19) {
41 realPath = FileUtils.getRealPathFromURI_API11to18(context, fileUri);
42 }
43 // SDK > 19 (Android 4.4) and up
44 else {
45 realPath = FileUtils.getRealPathFromURI_API19(context, fileUri);
46 }
47 return realPath;
48 }
49
50
51 @SuppressLint("NewApi")
52 public static String getRealPathFromURI_API11to18(Context context, Uri contentUri) {
53 String[] proj = {MediaStore.Images.Media.DATA};
54 String result = null;
55
56 CursorLoader cursorLoader = new CursorLoader(context, contentUri, proj, null, null, null);
57 Cursor cursor = cursorLoader.loadInBackground();
58
59 if (cursor != null) {
60 int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
61 cursor.moveToFirst();
62 result = cursor.getString(column_index);
63 cursor.close();
64 }
65 return result;
66 }
67
68 public static String getRealPathFromURI_BelowAPI11(Context context, Uri contentUri) {
69 String[] proj = {MediaStore.Images.Media.DATA};
70 Cursor cursor = context.getContentResolver().query(contentUri, proj, null, null, null);
71 int column_index = 0;
72 String result = "";
73 if (cursor != null) {
74 column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
75 cursor.moveToFirst();
76 result = cursor.getString(column_index);
77 cursor.close();
78 return result;
79 }
80 return result;
81 }
82
83 @SuppressLint("NewApi")
84 public static String getRealPathFromURI_API19(final Context context, final Uri uri) {
85
86 final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
87 // DocumentProvider
88 if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
89 // ExternalStorageProvider
90 if (isExternalStorageDocument(uri)) {
91 final String docId = DocumentsContract.getDocumentId(uri);
92 final String[] split = docId.split(":");
93 final String type = split[0];
94 // This is for checking Main Memory
95 if ("primary".equalsIgnoreCase(type)) {
96 if (split.length > 1) {
97 return Environment.getExternalStorageDirectory() + "/" + split[1];
98 } else {
99 return Environment.getExternalStorageDirectory() + "/";
100 }
101 // This is for checking SD Card
102 } else if ("home".equalsIgnoreCase(type)) {
103 return Environment.getExternalStorageDirectory() + "/documents/" + split[1];
104 } else {
105 return "storage" + "/" + docId.replace(":", "/");
106 }
107 }
108 // DownloadsProvider
109 else if (isDownloadsDocument(uri)) {
110 String fileName = getFilePath(context, uri);
111 if (fileName != null) {
112 return Environment.getExternalStorageDirectory().toString() + "/Download/" + fileName;
113 }
114
115 String id = DocumentsContract.getDocumentId(uri);
116 if (id.startsWith("raw:")) {
117 id = id.replaceFirst("raw:", "");
118 File file = new File(id);
119 if (file.exists())
120 return id;
121 }
122
123 final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(id));
124 return getDataColumn(context, contentUri, null, null);
125 }
126 // MediaProvider
127 else if (isMediaDocument(uri)) {
128 final String docId = DocumentsContract.getDocumentId(uri);
129 final String[] split = docId.split(":");
130 final String type = split[0];
131 Uri contentUri = MediaStore.Files.getContentUri("external");
132 if ("image".equals(type)) {
133 contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
134 } else if ("video".equals(type)) {
135 contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
136 } else if ("audio".equals(type)) {
137 contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
138 }
139
140 final String selection = "_id=?";
141 final String[] selectionArgs = new String[]{split[1]};
142 return getDataColumn(context, contentUri, selection, selectionArgs);
143 }
144 }
145 // MediaStore (and general)
146 else if (ContentResolver.SCHEME_CONTENT.equalsIgnoreCase(uri.getScheme())) {
147 // Return the remote address
148 if (isGooglePhotosUri(uri)) {
149 return uri.getLastPathSegment();
150 }
151
152 if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.N) {
153 return getFilePathFromURI(context, uri);
154 } else {
155 return getDataColumn(context, uri, null, null);
156 }
157 }
158 // File
159 else if (ContentResolver.SCHEME_FILE.equalsIgnoreCase(uri.getScheme())) {
160 return uri.getPath();
161 }
162
163 return null;
164 }
165
166 private static String getFilePathFromURI(Context context, Uri contentUri) {
167 File rootDataDir = context.getFilesDir();
168 String fileName = getFileName(contentUri);
169 if (TextUtils.isEmpty(fileName)) {
170 return null;
171 }
172 return copyFile(context, contentUri, rootDataDir + File.separator + fileName);
173 }
174
175 /**
176 * 获取文件名称
177 *
178 * @param uri
179 * @return
180 */
181 private static String getFileName(Uri uri) {
182 if (uri == null) {
183 return null;
184 }
185 String fileName = null;
186 String path = uri.getPath();
187 assert path != null;
188 int cut = path.lastIndexOf('/');
189 if (cut != -1) {
190 fileName = path.substring(cut + 1);
191 }
192 return fileName;
193 }
194
195 private static String copyFile(Context context, Uri srcUri, String dstFilePath) {
196 File dstFile = new File(dstFilePath);
197 try (InputStream inputStream = context.getContentResolver().openInputStream(srcUri);) {
198 if (inputStream == null) {
199 return null;
200 }
201 FileUtil.writeFromStream(inputStream, dstFile);
202 return dstFile.getAbsolutePath();
203 } catch (Exception e) {
204 Log.e("FileUtils", String.format(Locale.getDefault(), "copyFile: [%s]", e.getMessage()), e);
205 }
206 return null;
207 }
208
209 /**
210 * 通过游标获取当前文件路径
211 *
212 * @return 路径，未找到返回null
213 */
214 private static String getDataColumn(Context context, Uri uri, String selection,
215 String[] selectionArgs) {
216
217 final String column = MediaStore.Images.Media.DATA;
218 final String[] projection = {column};
219 try (Cursor cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null)) {
220 if (cursor != null && cursor.moveToFirst()) {
221 final int index = cursor.getColumnIndexOrThrow(column);
222 return cursor.getString(index);
223 }
224 } catch (Exception e) {
225 Log.e("FileUtils", String.format(Locale.getDefault(), "getDataColumn: [%s]", e.getMessage()), e);
226 }
227 return null;
228 }
229
230
231 public static String getFilePath(Context context, Uri uri) {
232
233 Cursor cursor = null;
234 final String[] projection = {
235 MediaStore.MediaColumns.DISPLAY_NAME
236 };
237
238 try {
239 cursor = context.getContentResolver().query(uri, projection, null, null,
240 null);
241 if (cursor != null && cursor.moveToFirst()) {
242 final int index = cursor.getColumnIndexOrThrow(MediaStore.MediaColumns.DISPLAY_NAME);
243 return cursor.getString(index);
244 }
245 } finally {
246 if (cursor != null)
247 cursor.close();
248 }
249 return null;
250 }
251
252 /**
253 * @param uri The Uri to check.
254 * @return Whether the Uri authority is ExternalStorageProvider.
255 */
256 private static boolean isExternalStorageDocument(Uri uri) {
257 return "com.android.externalstorage.documents".equals(uri.getAuthority());
258 }
259
260 /**
261 * @param uri The Uri to check.
262 * @return Whether the Uri authority is DownloadsProvider.
263 */
264 private static boolean isDownloadsDocument(Uri uri) {
265 return "com.android.providers.downloads.documents".equals(uri.getAuthority());
266 }
267
268 /**
269 * @param uri The Uri to check.
270 * @return Whether the Uri authority is MediaProvider.
271 */
272 private static boolean isMediaDocument(Uri uri) {
273 return "com.android.providers.media.documents".equals(uri.getAuthority());
274 }
275
276 /**
277 * @param uri The Uri to check.
278 * @return Whether the Uri authority is Google Photos.
279 */
280 private static boolean isGooglePhotosUri(Uri uri) {
281 return "com.google.android.apps.photos.content".equals(uri.getAuthority());
282 }
283 }
FileUtils
参考：https://www.jianshu.com/p/dc560ff4280d https://blog.csdn.net/jklwan/article/details/91650806
https://blog.csdn.net/weixin_43840649/article/details/104021296 https://blog.csdn.net/qq_32114025/article/details/129319259 https://blog.csdn.net/qq_18571109/article/details/127452296 https://gist.github.com/HBiSoft/15899990b8cd0723c3a894c1636550a8#file-fileutils-java 标签：文件,return,String,uri,URI,intent,管理器,null,final From： https://www.cnblogs.com/zt007/p/18112618