我希望我的应用程序的用户能够删除DCIM文件夹(它位于SD卡上并包含子文件夹)。
这可能吗?如果可能,怎么可能?
我希望我的应用程序的用户能够删除DCIM文件夹(它位于SD卡上并包含子文件夹)。
这可能吗?如果可能,怎么可能?
当前回答
这里是一个非递归的实现,只是为了好玩:
/**
* Deletes the given folder and all its files / subfolders.
* Is not implemented in a recursive way. The "Recursively" in the name stems from the filesystem command
* @param root The folder to delete recursively
*/
public static void deleteRecursively(final File root) {
LinkedList<File> deletionQueue = new LinkedList<>();
deletionQueue.add(root);
while(!deletionQueue.isEmpty()) {
final File toDelete = deletionQueue.removeFirst();
final File[] children = toDelete.listFiles();
if(children == null || children.length == 0) {
// This is either a file or an empty directory -> deletion possible
toDelete.delete();
} else {
// Add the children before the folder because they have to be deleted first
deletionQueue.addAll(Arrays.asList(children));
// Add the folder again because we can't delete it yet.
deletionQueue.addLast(toDelete);
}
}
}
其他回答
这是kotlin选项。它运行得很好。
fun executeDelete(context: Context, paths: List<String>): Int {
return try {
val files = paths.map { File(it) }
val fileCommands = files.joinToString(separator = " ") {
if (it.isDirectory) "'${it.absolutePath}/'" else "'${it.absolutePath}'"
}
val command = "rm -rf $fileCommands"
val process = Runtime.getRuntime().exec(arrayOf("sh", "-c", command))
val result = process.waitFor()
if (result == 0) {
context.rescanPaths(paths)
}
result
} catch (e: Exception) {
-1
}
}
//避免在一行中多次调用,它可以删除整个文件夹内容
fun Context.rescanPaths(paths: List<String>, callback: (() -> Unit)? = null) {
if (paths.isEmpty()) {
callback?.invoke()
return
}
var cnt = paths.size
MediaScannerConnection.scanFile(applicationContext, paths.toTypedArray(), null) { _, _ ->
if (--cnt == 0) {
callback?.invoke()
}
}
}
最快最简单的方法:
public static boolean deleteFolder(File removableFolder) {
File[] files = removableFolder.listFiles();
if (files != null && files.length > 0) {
for (File file : files) {
boolean success;
if (file.isDirectory())
success = deleteFolder(file);
else success = file.delete();
if (!success) return false;
}
}
return removableFolder.delete();
}
如果你不需要递归删除东西,你可以尝试这样做:
File file = new File(context.getExternalFilesDir(null), "");
if (file != null && file.isDirectory()) {
File[] files = file.listFiles();
if(files != null) {
for(File f : files) {
f.delete();
}
}
}
你可以像这样递归地删除文件和文件夹:
void deleteRecursive(File fileOrDirectory) {
if (fileOrDirectory.isDirectory())
for (File child : fileOrDirectory.listFiles())
deleteRecursive(child);
fileOrDirectory.delete();
}
这里是一个非递归的实现,只是为了好玩:
/**
* Deletes the given folder and all its files / subfolders.
* Is not implemented in a recursive way. The "Recursively" in the name stems from the filesystem command
* @param root The folder to delete recursively
*/
public static void deleteRecursively(final File root) {
LinkedList<File> deletionQueue = new LinkedList<>();
deletionQueue.add(root);
while(!deletionQueue.isEmpty()) {
final File toDelete = deletionQueue.removeFirst();
final File[] children = toDelete.listFiles();
if(children == null || children.length == 0) {
// This is either a file or an empty directory -> deletion possible
toDelete.delete();
} else {
// Add the children before the folder because they have to be deleted first
deletionQueue.addAll(Arrays.asList(children));
// Add the folder again because we can't delete it yet.
deletionQueue.addLast(toDelete);
}
}
}