Buttons to switch between modes - user-interface

I have an input that can be entered manually or computed automatically from other data. I can't just let the user override the automatic calculation because changes to other inputs can trigger a recalculation. My prototype associates a button with the input that switches between "Auto" mode and "Man" mode. In "Auto" mode the input is disabled and just reflects the calculated value.
I currently have the button label represent the current mode (e.g. "Auto" in auto mode) rather than the mode that pressing the button would produce. Could this be confusing? Is there a way to represent that the button is mode-changing (e.g. a double arrow icon etc.)?
This is kind of similar to mute/unmute.

Related

"Always show selection" doesn't work on CListCtrl in list mode

I want a user to be able to select item(s) in my CListCtrl and then click on a button to act on those items. But when the focus is lost from the list, the selection is no longer shown, even if I set 'Always show selection' to true:
This happens both in the dialog test facility, and in my compiled application. I use list-mode, and have no icons, only text.
To reproduce:
Create a new dialog in the resource editor
Place a list-view control.
Set View = List in the properties
Set Always Show Selection = True in the properties
Add a button to the dialog
Press Ctrl-T to test the dialog
Select item(s) on the list, then press the button
..and the text is not visibly selected at all. Or is it... I can just
barely sort of see some very very faint selection in my screenshot - I
think. It's so faint I am not 100% certain it's there!
In addition to my comments: well, there you have it - they are selected, and in a different color, but it seems your screen settings are a bit off. Maybe your color settings, a high contrast mode, or the color setting for selected items in Windows.
The gray color in your screenshot is: #f7f3f7 - light gray, so you might have a problem seeing it, depending on the settings.
An interesting and very lightweight tool to check those things (zoom in, see the color values) is ZoomPlus. I use it every day, and there seems to be source code available too.

Why do labels and frame have a "Tab Index" property in VB6?

Does anyone know why Labels and Frames (and possibly other controls) have a TabIndex property in VB6? Is there some use for it; some feature of GUI programming I ought to be incorporating in my applications (that I am blissfully unaware of)?
To confirm what Cody said in the comments. The VB6 manual entry for TabIndex says:
Controls that can't receive the focus (Frame and Label controls) remain in the tab order but are skipped during tabbing.
but
If you press the access key for a Frame or Label control, the focus moves to the next control in the tab order that can receive the focus.
TabIndex is the property used to determine the sequence of focused controls when user presses TAB key.
If control with TabIndex=5 is focused and user presses TAB, control with TabIndex=6 will take focus.

Efficiently subclassing standard Cocoa controls

In spite of there being a Human Interface Guidelines document (HIG), a lot of high quality Mac desktop applications use custom controls. My question is what is the best approach to start subclassing controls for Cocoa development? It surprises me how little (good) information there is on this topic. What path is the best to follow so you don't end up with a nice but half broken control?
Here's a checklist:
Make sure your control works correctly at double resolution. Use Quartz Debug to test this. You'll want to test both drawing sanity (in all states—normal, selected, pressed, disabled, and any others) and operation sanity (that hit testing matches where things appear on the screen/other destination device).
For extra credit, make sure your control works correctly at 1.5 (or some other, similarly non-integral) resolution.
Test how the standard control works when clicked. You'll probably do this anyway. Do as the standard control does.
Test how the standard control works when half-clicked (mouse down inside, mouse up outside).
Test how the standard control works when dark-side-of-the-clicked (mouse down outside, mouse up inside).
Test how the standard control works when dragged within.
Test above four with the other mouse buttons (right and middle).
Test what the standard control does when you scroll with a scroll wheel. Also test shift + scroll and, on a mouse that has them (e.g., most Logitech mice), scroll left/right buttons.
Test what the standard control does when you two-finger scroll in each axis and in both axes.
Test what the standard control does when you pinch and when you unpinch.
Test what the standard control does when you swipe with three and four fingers in each axis.
Test how the standard control works with “Full Keyboard Access” turned on. Can you tab into it? Can you press it with the space bar? Can you enter it with the return key? Can you tab out of it?
Test how the standard control responds to Accessibility queries. Use Accessibility Inspector. See the Accessibility Programming Guidelines for Cocoa for information on responding to accessibility queries and messages in your control.
Test your app—including, but not limited to, your custom controls—in VoiceOver. Blindfold yourself and try to use the app with VoiceOver alone.
If applicable, test printing your view. You can print to Preview if you don't want to kill a tree for your development process.
Test printing in other paper sizes. If you're in the US, test A4; otherwise, test US Letter. Test still other paper sizes (such as Legal and A3) if you're feeling thorough.
If you're implementing a scroller (poor you), test that your scroller responds correctly to the “Jump to the (next page|spot that's clicked)” preference in the Appearance pane in System Preferences. “Correctly” means it should do what the user selected.
Make sure it correctly implements all four scroll-arrow-position settings: One at each end (Mac style), both at the lower/left end (NeXT style), both at the upper/right end, and both at each end (power user style). As always, you need to both draw correctly and hit-test/react correctly. (Suggested by #radiofreelunch/by David Dunham)
Also, if you're implementing a scroller, make sure it responds to the “Smooth scrolling” preference correctly.
Test that it responds to different scrolling speed preferences correctly.
If you're implementing a text entry field of some sort, or any view that responds to some sort of special hot key (like Enter to send a message in an inputline), test right-to-left (Hebrew/Arabic) text input and alternate input methods. The Character Viewer is a good start.
Also, test that you don't break ctrl-q. For example, ctrl-q, tab should always enter a tab character. The same typically goes for option + (key), such as option-return in an inputline.
Test that it responds to different key-repeat preferences correctly.
If you implement any custom keyboard shortcuts (⌘ + zero or more other modifiers + one or more character keys) by means other than Cocoa's standard menu shortcut handling, test your custom shortcut behavior under Dvorak. There is no faster way to sour our perceptions of your app than to respond to ⌘' by quitting.
Show your app to users who've never used it nor seen any mockups before. Disqualify programmers. If they don't recognize your control as a (whatever it's supposed to be), redesign it. If you ever say “the scroller is over here” or “you need to click that”, you instantly fail.
Test that your control responds (or doesn't respond, if responding would be dangerous) when your app is in the background. (Suggested by #chucker.)
Test that your control responds, but does not bring the app forward, when your app is in the background and the user clicks on it with the ⌘ key down. (Suggested by #chucker.)
Test resizing your view. Among other things, this will ensure that you set the autoresize mask correctly. You're also looking for drawing bugs—distorted elements, gaps, etc. (Part of this suggested by #Bagelturf.)
If your control is, in fact, a control, send it sizeToFit and make sure that it does the right thing. (Suggested by #Bagelturf.)
If you work with mouse coordinates, don't assume that they will be whole numbers. Ensure that you handle fractional numbers, zeroes (positive and negative), and negative numbers correctly. (Part of this suggested by #Bagelturf.)
You might also consider splitting your control into a control and a cell. In the latter case, also perform all of these tests on your cell embedded in an NSMatrix and in an NSTableColumn.
If your control has a menu, test what happens when the control is at one or more edges of the screen. The menu should move over to not fall outside screen space.
If your control has a menu, test that the user can enter it with the down arrow key when using “Full Keyboard Access”. If it is also a text field (like a combo box), test that this only happens when the user presses the down arrow at the end of the text; otherwise, normal text field behavior should rule: Pressing down on a line that is not the last line should move the cursor down a line, and pressing down on the last line should move to the end of the line.
If your control has a menu, test that it stays open when clicked and does not immediately close when held open. There is a function you can use to do this correctly, and it is available in 64-bit.
If your control has a menu, test that it is navigable (all four arrow keys + Home, End, Page Up, Page Down), usable (spacebar/return press action), and cancellable (esc) with the keyboard.
Hard to add anything to Peter's list, but if you're doing a scroll bar, be sure it handles all the deviant placements of the scroll arrows (like DoubleBoth).

Should an icon show current state or next state?

When using icon images without text captions, should the icon represent the current state or the next state? For example I have a block of text that I want to minimize / maximize or I want to toggle showing All User Records or just My Records. I'm sure there are compelling arguments for either side and know that consistency is key, but what are the arguments related to good intuitive user design?
There is neither standardization nor general human tendency on this. For example, MS Windows UX Interaction Guidelines specifies four basic kinds of toggling progressive disclosure control. Three out of four show the state-when-activated, while one shows the current state.
I believe if you test a particular approach on your users, you'll get different results depending on what you ask. If you show them a control and ask them what state the app is in, they'll tend to read the icon as if it were indicating the state. If you show them a control and ask them to change the state (where in some cases the state is already changed), they'll read the icon as if it were the state to achieve. It's precisely because of this they invented toggling buttons.
If you're lucky, users use the icon primarily for either reading the state or setting the state, and not both. Then let the icon indicate whatever the users use it for.
If they indeed use it for both reading the state and setting the state, you're basically hosed, but there are a few things you can try to minimize hosehood:
Use text in addition to or instead of an icon. When labeled with a verb (e.g., "Connect"), the control indicates the state the user gets. When labeled with an adjective or noun (e.g., "On Line"), it implies the current state.
If your lib doesn't support toggling icons, then consider using a checkbox control, if that's allowed.
If your lib doesn't support checkboxes, then consider two controls, one to set each state, where the current state is disabled. Not too good for reading the current state, but there's some precedence for this in pulldown menus.
Fiddle with graphic design or placement to make it consistent with the meaning you've chosen. For example:
Command buttons are always labeled with the action they commit, so if your icon indicates the state the user gets, then give the icon a raised appearance like a command button. If the icon indicates the current state, then give it a flat appearance.
Toolbar controls usually show the state they bring about, so put the icon at the top of the window if indicates the state the user gets. In contrast, icons in the "work area" of the window indicate objects or attributes, so icons there should show the current state. Icons at the bottom of the window (in the status bar) should also show the current state.
This has not been truly standardized. Folder icons, for example, show open folders when they are open and closed folders when they are closed. Same for disclosure triangles, etc.
However, in other contexts, this is not always true. In a movie player, the "Play" arrow shows when the movie is not playing, and it shows the pause icon when it is playing. Probably the thing to do is use your best judgment, then poll your users. If a preponderance of the people you test are confused by your icon choices, switch them around. Then test them again and see if your initial test holds up. :)
If you are just going to have one button to toggle between two states, then the button should represent the next state, because that is the action that the button will take when clicked.
You gave the example of text that is minimized/maximized. Think of any expandable tree interface you ever see in Windows. A minimized tree has a [+] next to it, because clicking the button will expand the tree. And a maximized tree has a [-] next to it for the same reason.
You could also try to make a toggle that is highlighted or "pressed down" like mihi says, but that might be more confusing.
I prefer the "next state" approach (click plus to expand, click minus to collapse).
One reason is that this is the most widely used approach, so doing anything else would confuse users (and me as well).
Another reason is that the "next state" approach looks more inviting for the user to click.
May I present Zoom's mute button:
It shows the current state, as an icon, and the action that will occur when you push the button, as text. In other words, the icon on the button is the current state and the label on the button is the new state. The current state and the new state are opposites, so the button appears to contradict itself unless you read it very carefully.
(I hate that button.)

GUI: should a button represent the current state or the state to be achieved through clicking the button?

GUI: should a button represent the current state or the state to be achieved through clicking the button?
I've seen both and it sometimes misleads the user. what do you think?
The label on the button should reflect what the button does, i.e. it should describe the change the button makes.
For example, if you have a call logging system a button should say "Close Call" and the user can click it to close the call. The button should not have the label "Call is Open" and the user clicks to change the call status as that's very counter-intuitive, since the button is effectively doing the opposite to what it says on it.
In my opinion the label - and so the function - of a button should rarely, if ever, change. A button is supposed to be a like a physical button and they usually only do a single thing. (There are a few exceptions like play-pause on a media player where it's OK for the button label/icon to change, but at least this is copying a button from a real physical device.)
To carry on the example from above, I would say usually you would want two buttons, "Open Call" and "Close Call" and disable whichever one is not appropriate. Ideally you'd have a field elsewhere displaying the status of the call.
In summary, buttons are for doing things not for passing on information to the user.
The button should represent the action to be executed, not the state.
Some buttons are actions and are not ambiguous, like "Save", "Print" or "Enable user".
When a button represents a state that can be toggled, like Enable and Disable something, I do one of the following:
Change the button text, and make it always point to the state that will be achieved; (i.e. make the button point to actions, not states);
- Keep the button's text the same, but use one of those sticky buttons that will stay pressed, representing that the current state is "on" or "off". I prefer the former approach, though.
It should represent the action taken when clicking the button. States should always be presented by other means.
But I know what you mean. My car radio has buttons with text that shows the current state. It is really confusing.
This depends on the function which will be triggerd by the button click.
if the click changes the state of an entity i would suggest that the button represents the state the entity will enter after clicking the button
if the click triggers some kind of functionality the button should represent the function.
The appearance of the button is also a clue to its state. It should follow the standards of the environment if any exist (example, beveled edge / shadow appears on mouse click in Windows).

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