1、跳转到文件选择器进行文件选择
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);intent.addCategory(Intent.CATEGORY_OPENABLE);intent.setType("*/*");startActivityForResult(intent, REQUEST_CODE_SELECT_FILE);
2、在onActivityResult中对返回的数据进行处理
@Overrideprotected void onActivityResult(int requestCode, int resultCode, Intent data) {super.onActivityResult(requestCode, resultCode, data);if (requestCode == REQUEST_CODE_SELECT_FILE && resultCode == RESULT_OK && data != null) {if (ContextCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_DENIED) {showAlertDialog("打开文件失败，请允许读写手机储存。",new DialogInterface.OnClickListener() {@Overridepublic void onClick(DialogInterface dialog, int which) {dialog.dismiss();ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1);}});} else {String imgPath = getImageAbsolutePath(this, data.getData());Log.e("图片路径", "onActivityResult: " + imgPath);}}}/*** 提示对话框，带有“确定”按钮** @param message 提示内容* @param listener “确定”按钮的点击监听器*/private void showAlertDialog(String message, DialogInterface.OnClickListener listener) {AlertDialog dialog = new AlertDialog.Builder(this).setMessage(message).setPositiveButton("确定", listener).create();dialog.setCanceledOnTouchOutside(false);dialog.show();}
3、根据URI获取图片绝对路径
/*** 根据Uri获取图片绝对路径.** @param context 上下文* @param imageUri 图片的Uri* @return 图片绝对路径*/public static String getImageAbsolutePath(Activity context, Uri imageUri) {if (context == null || imageUri == null)return null;if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT && DocumentsContract.isDocumentUri(context, imageUri)) {if (isExternalStorageDocument(imageUri)) {String docId = DocumentsContract.getDocumentId(imageUri);String[] split = docId.split(":");String type = split[0];if ("primary".equalsIgnoreCase(type)) {return Environment.getExternalStorageDirectory() + "/" + split[1];}} else if (isDownloadsDocument(imageUri)) {String id = DocumentsContract.getDocumentId(imageUri);Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.parseLong(id));return getDataColumn(context, contentUri, null, null);} else if (isMediaDocument(imageUri)) {String docId = DocumentsContract.getDocumentId(imageUri);String[] split = docId.split(":");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;}String selection = MediaStore.Images.Media._ID + "=?";String[] selectionArgs = new String[]{split[1]};return getDataColumn(context, contentUri, selection, selectionArgs);}} // MediaStore (and general)else if ("content".equalsIgnoreCase(imageUri.getScheme())) {// Return the remote addressif (isGooglePhotosUri(imageUri))return imageUri.getLastPathSegment();return getDataColumn(context, imageUri, null, null);}// Fileelse if ("file".equalsIgnoreCase(imageUri.getScheme())) {return imageUri.getPath();}return null;}/*** 从本地设备数据库查询数据.** @param context 上下文* @param uri 内容提供者的标识* @param selection设置条件，相当于SQL语句中的where* @param selectionArgs 条件值* @return 查询结果*/public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {Cursor cursor = null;String column = MediaStore.Images.Media.DATA;String[] projection = {column}; //告诉Provider要返回的内容（列Column）try {cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);if (cursor != null && cursor.moveToFirst()) {int index = cursor.getColumnIndexOrThrow(column);return cursor.getString(index);}} finally {if (cursor != null)cursor.close();}return null;}/*** @param uri The Uri to check.* @return Whether the Uri authority is ExternalStorageProvider.*/public 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.*/public 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.*/public static boolean isMediaDocument(Uri uri) {return "com.android.providers.media.documents".equals(uri.getAuthority());}/*** @param uri The Uri to check.* @return Whether the Uri authority is Google Photos.*/public static boolean isGooglePhotosUri(Uri uri) {return "com.google.android.apps.photos.content".equals(uri.getAuthority());}
注意：给文件读写权限
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
