Bug report. Directory Opus hangs when filtering with "Filter folders in Flat view" option is on

Hello.

Recently I have been testing Directory Opus filtering and found that filtering with "Filter folders in Flat view" sometimes can lead to DOpus freeze.
My actions are:
Go to %PROGRAMFILES%. There are ~6000 folders and ~51000 files.
Turn on "Flat View" in mixed mode.
Type * for filter bar to pop up
Tick the "Filter folders in Flat view" checkbox.
Start typing, for example "photosh" without quotation marks.
And DOpus lister hangs for about five minutes, or to be exact one letter shows in the filter box and it freezes, two letters show in the filter box and it freezes, and so on till the end of the filter mask. But if I paste the text(whole filter mask) from the clipboard in one go, DOpus hangs only for about 10-12 seconds.

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Also can you explain why when a folder is filtered out in flat view mode, all files and subfolder within that folder are filtered too? This is illogical, because this practically limits folder filtering to the root of the directory where you are doing it unless upper level folders have same names as subfolders, e.g. \test107\test107 or \seven\seven. I mean, what is the point of making this option available only in flat view when you actually make flat view useless because you can't use filter to show subfolders that have different name from the folders they are in. It's like not using flat view at all.

Faster filtering in flat view is on our list for the future.

At the moment, it was not really designed for scenarios with 6,000 folders / 50,000 files. It'll work but it won't always be very fast.

Flat-View folder filtering, which is off by default, works that way because its purpose was to let you hide entire branches.

Considering both things, you may find Tools > Find Files more suited to what you're trying to do.

Leo, thanks for quick reply.

[quote="leo"]Faster filtering in flat view is on our list for the future.

At the moment, it was not really designed for scenarios with 6,000 folders / 50,000 files. It'll work but it won't always be very fast.
[/quote]

OK. I am fine with slow speeds if the don't lead to software freezes and crashes. :slight_smile: Also filtering 50000 files or 10000 files or even 500000 files is fast and does not hang the program, though the last one is a little bit sluggish, the problem occurs only when folder filtering is involved.

I am trying to say, that the purpose of flat view is to let you see and interact with the entire contents of the directory you're working in including files and subfolders, but in case of folder filtering you're in fact limited to the root of your working directory(unless subfolders have the same name as folders they are in), and it is as if flat view is turned off. I mean it's like using flat view without flat view advantages. To me it makes no sense.
Besides, if this filter options was available in default view you could have pretty much the same results in terms of folder filtering like in flat view, but in much less time and without wasting cpu cycles and memory space. Here is an analogy from real life. Your company owns a warehouse. It has 10 door, each one is marked with a special name and is leading to the separate room where the boxes with goods are stored. Boxes and goods are marked with a special name too. By the way, boxes and doors in this particular warehouse have different names. One day your boss appoints you to the task of taking a photo of every door, box and item in the box with a corresponding name(which is printed on the sheet of a paper) in the whole warehouse. You think "Okay, it can't be helped, this is my job, I have to do it". You start with checking doors names and if any of them has a name that matches what is written on the paper you were given by your boss, you take a photo of it, then you enter one of the doors and you do the same operation with the boxes, then with the items inside them, then you go to another door and so on. The cycle repeats till you check every room and every box in the warehouse. 8 hours passed you are tired but glad that you completed your task. You show results of your hard work to the boss, and suddenly he tells you "Sorry I forgot to mention that I don't need any box or item photo if their name is different from the one on the door that leads to room where they are stored". And you think "Wha, what the hell! Obviously he knows that the doors names differ from the ones on the boxes and items. Why he forced me to do all that useless stuff!? He probably hates me." What Directory Opus does on my PC is almost the same, it checks every file and subfolder if they match the filter, wasting my machine resources just to trim them in the end if they they don't match the name of the folder, where they are contained. And in vast majority of cases, not only on my PC, folder and subfolder have different names. That is why I don't understand what is the point in this kind of filtering in flat view. If you want to hide entire branches it would be more reasonable to at least make this option available in default view.
The best way of course is to have an option to choose between two modes. First one where everything that is inside the folder that does not match filter is hidden, like it is now. Second one where everything that matches filter is shown. Though personally I would use filtering + default view instead of first mode(way more faster and not so resource hungry), and if I need to filter files at the same time I would switch to dual view, activate flat view mixed(no folders) in the second pane and filter my files(fast and easy).