Winforms controlling controls - list

I couldn't think of a coherent search term for my problem so please forgive me if this has been asked before.
I have 24 combo boxes sitting on a panel control, displayed in 4 rows of 6.
After the user defines the value for each combo and hits the "go" button, I add all combo boxes to list so I can use the values in another section of my program.
The problem is that the order the comboboxes are added to the list is messed up, compared to their visual layout on the panel, and I would like to define the order. Currently, it adds the 9th combobox to the list first then the 20th, 2nd, 16th etc etc.
I tried TabIndex but that didnt work.
Before I manually rename and relabel all of the boxes, any other suggestions will be gratefully received.

The controls of your form exist in Controls collection of the container controls, for example when you add a Panel and a Button to a Form and two ComboBox to the Panel, then:
Form.Controls contains button1 and panel1
Panel.Controls contains comboBox1 and comboBox2
Controls are added to the Controls collection, with the same order that you add them to designer. Open designer.cs, look at the end of InitializeComponent to see the order.
You can also see/change the order using Document Outline window.
That said, now it should be obvious that panel1.Controls.OfType<ComboBox>() returns combo boxes with the same order that you see in Document Outline (or based on their z-index, and it doesn't have anything to do with their x/y placements).
You may want to order them based on TabIndex, or any other property that you like:
panel1.Controls.OfType<ComboBox>().OrderBy(x=>x.TabIndex)
Note
In general, if you are going to use those values for a search, instead of relying on the order of values, a much better idea is creating a SearchModel class which has a few properties, the set those properties to the selected value of the corresponding combo box (manually or using databinding) then pass the search model to the other classes.

Related

ListView32 - re-adding column doesn't restore data

I'm implementing show/hide column behaviour in a standard C++ Win32 application (no frameworks).
Say we've got 3 columns in a ListView control in Details view. The user has the option to show/hide the last two columns in order to see the extra detail if wanted or hide them to reduce clutter. All works well except that after the columns are deleted and then re-added, the data from the sub-items in those columns doesn't show up again, i.e. the columns are empty.
None of the items themselves have been altered in the meantime - do I lose the sub-item text when I delete the columns or I am missing something to force the columns to redraw the data?
Steps to reproduce:
1) Create a ListView32 control with 3 columns and add a bunch of items (and text to each of the items' sub-items). All good.
2) The user clicks "Hide Details", so I use LVM_DELETECOLUMN twice to remove the last two columns and they disappear. All good.
3) The user clicks "Show Details", so I use LVM_INSERTCOLUMN to add the last two columns and the headings appear, but the columns themselves are empty.
As an alternative, setting the column widths to zero is a hack and the user can still grab the re-size column splitter, so it's not a great option.
Many thanks for any suggestions.
Typically one does not store data in GUI. In case of plain listview32 you should add items specifying LPSTR_TEXTCALLBACK instead of real text and then handle LVN_GETDISPINFOW notification supplying (sub)item data. Windows will send this notification for all items. You can force Windows to retrieve data again by sending LVM_UPDATE message.
Setting the column widths is a viable solution. That is the way I do it in my UIs when columns can be shown and hidden dynamically. It works fine.
To prevent the user from resizing "hidden" columns, simply subclass the ListView using SetWindowLongPtr(GWL_WNDPROC) or SetWindowSubclass() to intercept HDN_BEGINTRACK notifications from the ListView's header control:
Notifies a header control's parent window that the user has begun dragging a divider in the control (that is, the user has pressed the left mouse button while the mouse cursor is on a divider in the header control). This notification code is sent in the form of a WM_NOTIFY message.
...
Returns FALSE to allow tracking of the divider, or TRUE to prevent tracking.

Change label of QComboxBox without using lineEdit

Currently I want to implement a widget to allow user to enable/disbale all provided options of a QSet. So i took a combobox and added selectable items. So far so good, but how I can change text displayed in combobox? Currently all my items have just ItemIsUserCheckable and ItemIsEnabled as enabled flags (ItemIsSelectable is not enabled), so text of ComboBox is always text of first item. Instead I want as text "Flag1, Flag 3, Flag6" if there multiple flags and user enabled Flag 1, 3 and 6. But setCurrentText and setEditText requiring setEditable(true) or an custom lineEdit. But using an lineEdit is changing appearance. So is there another way?
I had a similar problem a while back, I ended up 'solving' it by adding an extra item to my model that was first in the list and always set as the current item. I then updated it's text to say 'Select items...' or 'X item(s) selected' as appropriate.

Tkinter - Changing the list in Option Menu

Is there a way to manipulate the List displayed by the OptionMenu in respect to what the user has currently selected?
For example, let's say I have a list - ["A","B","C"].
If the user currently selected A then if he clicks the optionmenu with A currently selected, what he will see in the list is not the original list but only B and C.
If he switches his answer from, let's say, A to B, then now, he will only see A and C in the OptionMenu.
And the same will follow if he chose B or C.
Thanks!
The OptionMenu widget is a button that shows a dropdown menu when pressed. You might do better to use a ttk.Combobox instead as that is a more modern UI element and you can very simply configure the values configuration item.
You can configure the attached menu at runtime. You access the menu using optionmenu['menu'] and you can then query items on the menu optionmenu['menu'].entrycget(0, 'label') or use entryconfigure to modify the items. Or you can delete items optionmenu['menu'].delete(index) and add new items. See the menu documentation for hints on manipulating the menu entries.

Dealing with huge select lists

I often use select lists with my projects but when it comes to a huge select list, I couldn't find a solution. I need a easy, plug and play solution for solution will be used in a few places.
When you have a select box or text box to be filled from a model data, I want to show user a text box, right side of text box, there should be a button to choice the value. Upon clicking that button, popup or a modal will be opened and I filter all the records and find my value, upon clicking value, modal or popup closes and I get choosen value to form control.
İmagine you have a text box to choose your customer, and among 2500 customer,
PS:don't suggest autocomplete, don't want to accomplish it.
Why don't you look at something like Chozen plugin http://harvesthq.github.io/chosen/. It allows you to easily search large select lists

User interface for reordering a list items

I have a list of items as a part of a web application. The question is how user can manipulate the order of items in the list (not the list sort order). The typical way is to use arrow buttons to move items up or down. The other way is the drag-and-drop.
But are there any other ways for a user interface for list reordering?
There are two other sorting methods (besides those you mentioned) I've seen which work pretty well.
Click To Move
The method used for ordering items in the Gallery web photo album works pretty well for ordering photos, and it should work just as well for any set that can be represented as a sorted group of clickable elements:
Present your list of items as clickable elements.
Clicking an element "selects" it, it is highlighted to indicate it's selected.
Clicking another item moves the selected item to a position just before the clicked item.
Repeat until all items are in the desired order.
A dummy item is shown at the end of the list for moving items to the end.
This is slightly easier to use than drag-n-drop as it requires less dexterity, and you don't have to hold down the mouse button while you figure out where you want to "drop" the item.
The method could easily be extended to allow selection of multiple items (via shift-click or similar) which could then be placed in a new position in the same way.
Provide Order Numbers
Used by Netflix and some internal apps I've worked with. This works best if your users have a concrete idea of exactly what the numeric order should be (used when working with lists of instruction steps in our internal app).
Present your list of items one per line.
Provide a text entry box next to each item where the order number is displayed, starting with 1.
The user changes the order numbers in the text fields as desired.
If multiple items are given the same order number, they are placed next to each other.
Provide a button to "apply" the sort in JavaScript so that the user doesn't have to submit the entire page to see the re-arranged list. This makes it easy to work in increments.
Edit: A couple of additional thoughts on Drag-and-Drop. You might have used these before or not, but there are a few things that can make drag-and-drop more forgiving and easier to use:
Highlight the area where the item will appear when dropped. For example, show a prominent horizontal line between the two existing items where the item will be inserted if it is dropped.
Ghost the draggable item as it is dragged so that it's obvious what's being moved, rather than using a generic "dragging" cursor. This works best if the items being dragged are still legible if shown on top of one another with transparency.
Make sure the target areas where the draggable can be dropped are sufficiently large. Larger areas can be helpful for people who have trouble with the required coordination.
We've found that drag and drop can be counter intuitive for non-technical people. We have explored the Up Down Arrow which works but can also be cumbersome as you need to keep clicking up and down and it results in a lot of traffic.
Another paradigm we've explored is the Move button so each item in a list has a Move Item button when you click it new buttons are added before and after each item in the list to let you move the item to any location.
This works well when each item in the list takes a lot of space, if each list item is only a single row it can result in a cluttered interface. In our case each item was half a dozen lines of text or more. We also have add item here button before / after each item to allow insertion.
Survey Monkey uses this paradigm as well and inspired some of what we do.
Some thoughts - Very much on the ideas rather than implementation end though...
1 - Provide both up and down arrows and drag and drop, and monitor which is more popular, which type of users use which etc, then tailor from there once you have some data
2 - Add a "random" button which generates the order randomly - could be useless, could be fun depending on your app
3 - Add a "display order" field by the side of each item and allow the user to manipulate it (but make sure that you have some code to auto update the rest of the numbers when one changes) personally I think this could be very confusing, but for some users it might work
4 - Instead of drag and drop in place, have users drag to a new list
5 - For a very simple version, have a "favourite" check box, and then have the list just show the favourites first, (in alphabetical order or something)
6 - Have groups - you assign a group number to an item, all the group ones appear first, followed by group 2 etc
Hope this random rambling has been useful, if i think of anything more I'll come back...
1) A variation of Click to Move would involve having a separate target list, where the user selects the slot into which their item will move, then clicks on the original item to move it.
For example, in the following diagram, the user has already put 'E' at the head of the reordered list and has selected slot three for their next choice. Their next step would be to choose which item from the old list goes into slot three on the new list. (The row of asterisks is a feeble attempt to show that slot three is highlighted or selected.)
old new
----- -----
| A | | E |
| D | | |
| C | |*****|
| | | |
| B | | |
----- -----
Clicking on an item in the new list selects it and highlights its original slot in the old list, which is now a target. Clicking on the item a second time returns it to that original slot.
The new list should also display indicators of some sort to show that it has selectable regions, perhaps unobtrusive (low-opacity) numbered buttons in its slots or some other informative affordance.
2) Another approach would be to allow users to draw lines between the original and desired positions.
Whatever method is chosen, the process need not be chatty: there's no reason this couldn't all be done client side (with the option to save and commit changes to the server).
You can experiment with drag-and-drop using the examples of jQuery UI Sortables.
To make it obvious for the non-technical or new users you could use visual cues such as handles or arrows and maybe a tooltip on hover to suggest dragging the element.
You could even provide an animated gif demonstrating the gesture.
As soon as a user learns how to do this I think it's the easiest method of ordering a list.
Another way is to provide a small text input next to every item, so the user can enter a numerical ordering themselves; then they click a button to reorder it all at once. (I've only seen this used on sites that store the order of items, such as Netflix queue or Livejournal links.)
Sorting, by clicking on headers is very popular. Perhaps only considered as a reordering of the view of the actual list, though.
Implement a copy/paste style function? This would mean you can take an item out of the list, and then select another item, and click "paste" or CTRL+V. This is quite intuitive and would allow large lists to be manipulated easily.
You could implement multi-selection easily to move a large block of adjacent items.
Network traffic would be low (only one or two requests).
You need to make sure the "paste" is consistent. I.e. pasting always inserts above the selected item.
Take a look at Checkvist for more inspiration.
You could also use arrow keys to move up and down.
I actually think the iphone / itouch does this really well when moving application icons.
If you haven't seen it look here: http://www.youtube.com/watch?v=qnXoGnUU6uI
The 'shaking' icons are a very good visual cue that something is moveable/draggable.
So I would suggest this approach with drag an drop. Clicking and holding on an item could put it in 'moveable-mode' and this would be indicated by it shaking (or some easier to code visual cue). Then drag and drop would work in the normal way.
Implementing this in javascript is of course the challenge...
Also another thing to think about - most people make the mistake of conflating usability with learnability. Think who the users of this app are (will they use it regularly and be taught how to use it, or are they public web users who may use it infrequently and not be taught how to use it) - it might give you a different answer to what the solution should be.
To me, performing a drag and drop of list elements in place (i.e. within the list itself) is the best approach.
Not only you can give to your users the immediate idea of what their list will look like (the list is reorganizing before their eyes), but it's also very easy for them to understand the moving mechanism.
And this is the briefest way to have your users ordering the list in the shortest number of moves.
By the way, foreseeing that a list could be longer than few elements, alongside the DnD method you could provide an asynchronous way to order the list: give the user the ability to attribute an ordering number to each entry, and then click on the "Order" button.
Handling in a smart and correct way user's input, this could result in a speed up for longer lists editing.
I was thinking of "Move selected to here":
Let all items be selectable by checkboxes
Let all items have a button or icon meaning "Move selected to here"
When "Move selected to here" is clicked, all selected items are moved to this item in existing order
The edge-cases here are when the items should be moved to either end of the list. One way to solve that, is to move all selected items before the target, and reserve a special button/icon at the end to move the selection there.
I've found the following to be the quickest way to allow specifying item order regardless of list size:
1) If user wants to set the order of list/grid items, they click a "Reorder" button.
2) This opens the reordering dialog which can be used with any list or grid.
3) In the dialog, all of the items are shown in their current order in a list on the left. There is an empty list on the right.
4) The user clicks the items in the left list in the desired order. When an item is clicked, it is removed from the left list and placed in the right list in the next position. In a worst case reordering where every item needs a new order, this allows ordering a list of N items with N clicks.
5) The user can then apply the new order or cancel. Applying the order results in the "display order" field in the data being set to the final order of the items in the right list. You can decide if the "Apply" button is only enabled when the left list is empty.
6) Also available in the ordering dialog are the following controls:
a) A button to move all of the items from the left list to the right list maintaining whatever order they are in
b) A button to start over by reloading the left list in its original order and clearing the right list.
c) A button to sort the right list alphabetically (or by date or numerically depending on what the key field is)
d) Drag and drop capability in the right list to manually drag items into order.
e) An index number column in the right list which, if edited, moves the item to that position.
This provides the best of all worlds. If you have a huge list where only a few items need to be moved, move all items over, then drag the few items where desired or enter the desired index. If you have a small-ish list that needs to be completely reordered, just click the items in the desired order. And so on.
I've used this approach for many years and it has been very effective.
You can show 'Up' and 'Delete' buttons just the way Google does for SearchWiki. Most of the people have at least some experience with it now. Most people bother only with 'Upping' their choice. If they do not like a thing, and want to downvote it, removing from the list with help of the abovementioned 'Delete' button will be easier for them
You could show an overlay when hovering over an element. This overlay shows you 4 arrows (n/e/s/w) and u can click and move the element accordingly.
If you are trying to oder items across a grid like facebook's and picasaweb's photo grouping features, then that is about the only way to handle that
if you had 3 columns each with a list of items, clicking on any of the items would move the item either to the left or right, middle column could show option for left or right. you could still allow for dragging and dropping or sorting using the typical functionality for that.