我正在从我的应用程序中删除图像文件。我在做什么
new File(filename).delete ();
这实际上是删除了该文件。但是图片仍然可以在画廊中看到。
在搜索中我发现我们应该使用
getContentResolver().delete(Uri.fromFile(file), null,null);删除
但在这里我得到了例外：
未知文件网址。 java.lang.IllegalArgumentException：未知的URL 文件：///mnt/sdcard/DCIM/Camera/IMG_20120523_122612.jpg
当我看到任何文件浏览器时，会出现此特定图像。请帮我解决这个问题。有没有其他方法可以在物理删除图像时更新图库
答案 0 :(得分：34)
我看到很多答案暗示使用
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://" + Environment.getExternalStorageDirectory())));
这有效，但会导致Media Scanner重新扫描设备上的媒体。更有效的方法是通过Media Store内容提供商进行查询/删除：
// Set up the projection (we only need the ID)
String[] projection = { MediaStore.Images.Media._ID };
// Match on the file path
String selection = MediaStore.Images.Media.DATA + " = ?";
String[] selectionArgs = new String[] { file.getAbsolutePath() };
// Query for the ID of the media matching the file path
Uri queryUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
ContentResolver contentResolver = getContentResolver();
Cursor c = contentResolver.query(queryUri, projection, selection, selectionArgs, null);
if (c.moveToFirst()) {
// We found the ID. Deleting the item via the content provider will also remove the file
long id = c.getLong(c.getColumnIndexOrThrow(MediaStore.Images.Media._ID));
Uri deleteUri = ContentUris.withAppendedId(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, id);
contentResolver.delete(deleteUri, null, null);
} else {
// File not found in media store DB
}
c.close();
答案 1 :(得分：28)
使用下面的代码，它可能对您有帮助。
File fdelete = new File(file_dj_path);
if (fdelete.exists()) {
if (fdelete.delete()) {
System.out.println("file Deleted :" + file_dj_path);
} else {
System.out.println("file not Deleted :" + file_dj_path);
}
}
刷新图库使用以下代码发送广播
（适用于＆lt; KITKAT API 14）
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://" + Environment.getExternalStorageDirectory())));
对于＆gt; = KITKAT API 14使用以下代码
MediaScannerConnection.scanFile(this, new String[] { Environment.getExternalStorageDirectory().toString() }, null, new MediaScannerConnection.OnScanCompletedListener() {
/*
* (non-Javadoc)
* @see android.media.MediaScannerConnection.OnScanCompletedListener#onScanCompleted(java.lang.String, android.net.Uri)
*/
public void onScanCompleted(String path, Uri uri)
{
Log.i("ExternalStorage", "Scanned " + path + ":");
Log.i("ExternalStorage", "-> uri=" + uri);
}
});
因为：
ACTION_MEDIA_MOUNTED
在KITKAT（API 14）中已弃用。
已于2015年9月9日编辑
下面代码
的工作正常检查public void deleteImage() {
String file_dj_path = Environment.getExternalStorageDirectory() + "/ECP_Screenshots/abc.jpg";
File fdelete = new File(file_dj_path);
if (fdelete.exists()) {
if (fdelete.delete()) {
Log.e("-->", "file Deleted :" + file_dj_path);
callBroadCast();
} else {
Log.e("-->", "file not Deleted :" + file_dj_path);
}
}
}
public void callBroadCast() {
if (Build.VERSION.SDK_INT >= 14) {
Log.e("-->", " >= 14");
MediaScannerConnection.scanFile(this, new String[]{Environment.getExternalStorageDirectory().toString()}, null, new MediaScannerConnection.OnScanCompletedListener() {
/*
* (non-Javadoc)
* @see android.media.MediaScannerConnection.OnScanCompletedListener#onScanCompleted(java.lang.String, android.net.Uri)
*/
public void onScanCompleted(String path, Uri uri) {
Log.e("ExternalStorage", "Scanned " + path + ":");
Log.e("ExternalStorage", "-> uri=" + uri);
}
});
} else {
Log.e("-->", " < 14");
sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://" + Environment.getExternalStorageDirectory())));
}
}
下面是日志
09-04 14:27:11.085 8290-8290/com.example.sampleforwear E/-->﹕ file Deleted :/storage/emulated/0/ECP_Screenshots/abc.jpg
09-04 14:27:11.085 8290-8290/com.example.sampleforwear E/-->﹕ >= 14
09-04 14:27:11.152 8290-8290/com.example.sampleforwear E/﹕ appName=com.example.sampleforwear, acAppName=/system/bin/surfaceflinger
09-04 14:27:11.152 8290-8290/com.example.sampleforwear E/﹕ 0
09-04 14:27:15.249 8290-8302/com.example.sampleforwear E/ExternalStorage﹕ Scanned /storage/emulated/0:
09-04 14:27:15.249 8290-8302/com.example.sampleforwear E/ExternalStorage﹕ -> uri=content://media/external/file/2416
答案 2 :(得分：23)
File file = new File(photoUri);
file.delete();
context.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, Uri.fromFile(new File(photoUri))));
此代码适用于我，我认为最好使用Intent.ACTION_MEDIA_MOUNTED
答案 3 :(得分：13)
要删除图片，
ContentResolver contentResolver = getContentResolver();
contentResolver.delete(MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
MediaStore.Images.ImageColumns.DATA + "=?" , new String[]{ imagePath });
答案 4 :(得分：5)
我尝试了所有这些解决方案，但在Android 6中没有运气。
最后，我发现这段代码运行正常。
public static void deleteFileFromMediaStore(final ContentResolver contentResolver, final File file) {
String canonicalPath;
try {
canonicalPath = file.getCanonicalPath();
} catch (IOException e) {
canonicalPath = file.getAbsolutePath();
}
final Uri uri = MediaStore.Files.getContentUri("external");
final int result = contentResolver.delete(uri,
MediaStore.Files.FileColumns.DATA + "=?", new String[]{canonicalPath});
if (result == 0) {
final String absolutePath = file.getAbsolutePath();
if (!absolutePath.equals(canonicalPath)) {
contentResolver.delete(uri,
MediaStore.Files.FileColumns.DATA + "=?", new String[]{absolutePath});
}
}
}
我还在Android 4.4和5.1中对此进行了测试，它运行良好。
答案 5 :(得分：4)
sendBroadcast(new Intent(
Intent.ACTION_MEDIA_MOUNTED,
Uri.parse("file://" + Environment.getExternalStorageDirectory())));
此代码有效，但资源非常昂贵。它卸下了＆amp;然后安装SDCard可能会影响某些应用程序或占用大量系统资源以刷新库。我仍然在寻找一个最好的选择＆amp;如果我得到，我会发布。
答案 6 :(得分：0)
在Kotlin中，您可以这样做：
private fun deleteImage(path: String) {
val fDelete = File(path)
if (fDelete.exists()) {
if (fDelete.delete()) {
MediaScannerConnection.scanFile(this, arrayOf(Environment.getExternalStorageDirectory().toString()), null) { path, uri ->
Log.d("debug", "DONE")
}
}
}
}
答案 7 :(得分：0)
我遇到了同样的问题，并且尝试了三种不同的方法来删除图像。有时它正在工作，有时却没有。现在花了太多时间后，我拥有的每种方法都会删除图像。我要说的是：请谨慎处理位图。我正在拍照，坚持下去，然后根据需要旋转：
public static Bitmap rotatePictureToPortraitMode(String filePath, Bitmap myBitmap) {
try {
ExifInterface exif = new ExifInterface(filePath);
int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, 1);
Log.d("EXIF", "Exif: " + orientation);
Matrix matrix = new Matrix();
if (orientation == 6) {
matrix.postRotate(90);
} else if (orientation == 3) {
matrix.postRotate(180);
} else if (orientation == 8) {
matrix.postRotate(270);
}
myBitmap = Bitmap.createBitmap(myBitmap, 0, 0, myBitmap.getWidth(), myBitmap.getHeight(), matrix, true); // rotating bitmap
} catch (Exception e) {
}
return myBitmap;
}
之后，我尝试删除该图像，但正如我之前所说，它不起作用。删除此方法有助于解决问题。
也许这只是我的问题，但是一旦我删除了它，对我很有帮助，所以我想特别注意一下您如何处理图像。就我而言，我使用了前面提到的答案：
File file = new File(photoUri);
file.delete();
context.sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE,
Uri.fromFile(new File(photoUri))));
希望有帮助！
答案 8 :(得分：0)
public static boolean deltefolderwithimages(File dir) {
if (dir.isDirectory()) {
String[] children = dir.list();
for (int i=0; i<children.length; i++) {
boolean success = deltefolderwithimages(new File(dir, children[i]));
if (!success) {
return false;
}
}
}
return dir.delete();
}
答案 9 :(得分：0)
DocumentFile.fromSingleUri(context, uri).delete();
对我来说很棒