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
public static void deleteDirectory( File dir )
{
if ( dir.isDirectory() )
{
String [] children = dir.list();
for ( int i = 0 ; i < children.length ; i ++ )
{
File child = new File( dir , children[i] );
if(child.isDirectory()){
deleteDirectory( child );
child.delete();
}else{
child.delete();
}
}
dir.delete();
}
}
我知道的最安全的代码:
private boolean recursiveRemove(File file) {
if(file == null || !file.exists()) {
return false;
}
if(file.isDirectory()) {
File[] list = file.listFiles();
if(list != null) {
for(File item : list) {
recursiveRemove(item);
}
}
}
if(file.exists()) {
file.delete();
}
return !file.exists();
}
检查文件是否存在,处理空值,检查目录是否被实际删除
根据文档:
如果此抽象路径名不表示目录,则此方法返回null。
所以你应该检查listFiles是否为空,如果不是则继续
boolean deleteDirectory(File path) {
if(path.exists()) {
File[] files = path.listFiles();
if (files == null) {
return false;
}
for (File file : files) {
if (file.isDirectory()) {
deleteDirectory(file);
} else {
boolean wasSuccessful = file.delete();
if (wasSuccessful) {
Log.i("Deleted ", "successfully");
}
}
}
}
return(path.delete());
}
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()
}
}
}
让我告诉你第一件事你不能删除DCIM文件夹,因为它是一个系统文件夹。当你在手机上手动删除它时,它会删除该文件夹的内容,但不会删除DCIM文件夹。您可以通过以下方法删除其内容:
根据评论更新
File dir = new File(Environment.getExternalStorageDirectory()+"Dir_name_here");
if (dir.isDirectory())
{
String[] children = dir.list();
for (int i = 0; i < children.length; i++)
{
new File(dir, children[i]).delete();
}
}