I have multiple controls on one form,and when i select some value from combo box(for example 1) next control became enabled, else next control stay disabled.
Problem is that if i just press 1 and tab, after that next control became enabled, but program jump over it just like control are still disabled, and tab control selecting next control.
I need to find way how to tab check is control become enabled and go on this control,and if control are still disabled that go on next enabled control.
Thanx
You created a mousetrap for the user, very hard to escape from. Technically you can handle the keyboard navigation by trapping the Tab key before it can be used to navigate but the user still has an unsolvable problem when he wants to use the mouse to change the focus. He has nothing decent to click on.
You'll need to re-think your UI design. One possible solution is to change the ComboBox's DropDownStyle to DropDownList. Which ought to be pretty appropriate if you use its selected item to enable other controls, there should only be a limited set of valid selections. If that's not what you want then you need to do something drastic. Not necessarily limited to hiding controls instead of disabling them.
This is probably caused by the event of the combo-box you using to control your flow.
The "Changed"/"Value changed" events in most languages fire up after the control has lost focus.
You forgot to add a tag for the UI technology you are using.
If you are using WinForms, then you can try to execute the SelectNextControl method on your control that the user just edited. This will find the 'next' control for you, and activate it.
Lets assume it's winforms (playing with disabled/enabled like this in wpf is.. against mvvm rules).
Firstly, ensure what tab order/index of your controls is ok. To test, if they are all enabled, then pressing Tab should go through them in the right order. This can be seen easily
Next thing is to choose one of many possible solutions, to make 1,Tab to work:
disable Tab key navigation at all;
make controls to pass control (focus) to specific control (making tab order irrelevant);
use SelectNextControl (work best for custom controls, which when will support that tab-flow schema);
prevent focus changing, do all logic, change focus (theoretically).
Related
I am working on a project in which I am using a property grid to display the properties of the selected control.
The Property Grid is fixed to the left edge of the container and in the rest of the space I have the form I am designing.
On clicking a control on the form, the specific control’s property is getting selected.
In the above figure, I have selected the textbox and the textbox’s properties get shown on the propertygrid.
Here if you observe, by default, the Name property is highlighted as well.
Is there some way to unselect this property programmatically?
I have tried some suggestions online but none have helped. I am not able to find find a way to remove all selections from the PropertyGrid, but its behaviour seem to be different form a DataGrid...
Here is why I need this...
On selecting a control, if a property in the property grid is selected, then the property is getting modified.
For example, If i cut the control using Ctrl + X, the selected value in property grid is getting cut which in some cases is forcing user to set the property before modifying anything on the form.
I have tried selecting multiple controls, but in that case alse the selected property seems to be persistent
Since PropertyGrid uses DefaultProperty to select a property in its grid, as an option you can set DefaultProperty attribute at run-time for your object to a non-browsable property, for example:
this.propertyGrid1.SelectedObject = null;
TypeDescriptor.AddAttributes(someControl,
new Attribute[] { new DefaultPropertyAttribute("Site") });
this.propertyGrid1.SelectedObject = someControl;
Well, what you are trying are hacks. It is never a good idea to do such hacks particularly if you are not the only person that use the software.
In your case, the focus should be on the designer while you interact with it. So if the user press Ctrl+X, the designer should respond to the keyboard and it should not have any effect on the property grid (as only one control can have the focus at the same time).
Thus it is up to you to make sure that your designer is focusable, that it has the focus when initially displayed, that it get the focus when you press the TAB key. Pressing the TAB key again should put the focus on the property grid so that user can interact with the grid without using the keyboard.
If you have more than these 2 controls, then obviously TAB should also stop at any appropriate controls. Also, it can be a good idea to have some direct shortcuts like F4 to (show and) activate the properties pane.
If you are not able to make it works, then the best compromise would be to use another windows for the properties grid. By using a distinct Tool windows for the properties, it should not respond to the keyboard when the main windows has the focus.
Here are some links that might help you:
Panel not getting focus
Control.Focus Method() — See Remarks section.
In any case, you should not prevent Ctrl+X to works as expected when the property grid has the focus and a property is selected. Users don't like software that do not follows UI conventions.
As a software developer, you should as much as possible ensure that your application follows standard behaviors. I recommend you that you take one or 2 extra days developing your software properly instead of doing hacks.
Often, compromise to gain a few days will never be fix and will be a pain for many years. Better to do it right from the start. Unselecting an item in the property grid is not an acceptable workaround. Your manager should not allows you to do that.
I am not getting it after quite a research, that how can I implement simple Lostfocus like we use to do in Winforms. In Windows Form Control, we usually have LostFocus which I use when someome press TAB to lose focus or use mouse to select other controls. But it is not the case with WPF. I first use LostFocus, but when i press tab it doesn't fire the event. however when I click using mouse to other control it does get fired properly. So, this doesn't solve my problem.
Second, I try to use LostKeyboardFocus, it does get fired when using TAB key, and on few occassion when I use mouse to select other element, but not when I select menu item from Parent window menu.
Also, I have my control on User Control, that I put in TAB control on parent window. But when I press TAb key it always select the Parent Window Menu instead of TreeView I have in UserControl.
Any suggest is great help. Thanks.
Well, my quest for finding logically reasoning is still not satisfied, but I get the simple thing done simply.
#Daniel, as I said I think the two questions are related, well the answer is indeed related. Maybe you can explain my finding that I am putting as answer here.
I simply set the TabIndex property of my Textbox and other control [TreeView] as 1 and 2, now when I press TAB or select the TreeView item using mouse, i got Lostfocus fired up. and since I have Tab Index set within control, it doesn't select Menu item of parent [it does select it as last now]. So that make Lostfocus the function I should use for my purpose.
Anyone with explanation or better solution is still requested to share it. Thanks.
I need to create a control which has a single permanent tab ("home"), and all of the other tabs are scrollable.
Right now I am trying to achieve this result by subclassing the TabControl, adding an extra button (which looks like a tab) to the overridden template, and setting the SelectedIndex to -1 whenever the button is clicked. When SelectedIndex is -1, a trigger causes the TabControl's ContentControl to be bound to a special "Home" tab's content. Basically, I am faking the behavior of a real tab and overriding the ability to deselect all tabs in doing so.
This seems to work, except for two problems:
Select example tab #3, then select home. THEN, try to select tab #3 again. Tab #3 doesn't respond.
Select tab #3, then select home. THEN, try to use the menu which happens to be in the same window. When I go to use the menu, #3 pops up as the selected tab again.
I've tried to listen to all kinds of events associated with the TabControl at this point, but none of them seem to give me something I can work with to get around these behaviors.
Is there something out there that will allow me to override the default SelectedIndex behavior? Should I be doing this another way? Ideally, I would like some way to take in a collection of tabs that allows me split up the tabs visually without losing the basic functionality of a TabControl.
The only way I can think of to accomplish this would be to use a custom ControlTemplate for the tab control. You can use StyleSnooper to get the current template. The that is part of that template would need to be replaced with a custom panel that you wrote. You base that on Panel. You would only need to override ArrangeOverride so that it arranged the Home tab in its place, and the others depending on the scroll position.
I was able to implement this by writing my own custom tab panel, as AresAvatar suggested. However, the panel needed to extend from the ConceptualPanel implementation from http://www.codeproject.com/KB/WPF/ConceptualChildren.aspx. The problem is that the panel needs to have IsItemsHost="true" in the TabControl template to preserve the tabs' selection behavior. Unfortunately, once a normal panel is an items host, it's Children can't be changed from inside it's own class code. So, I couldn't add the scroll buttons that I needed. I was able to get around that problem with the ConceptualPanel by adding everything (tabs + scroll buttons) via AddVisualChild.
There might be a better way to do this, but this worked for me.
I am not fully sure about this, but I seem to be observing cases where focus shifts automatically from one control to another, even after I explicitly programmatically set the focus to control that I want to have focused. Maybe it has to do with the control in question being a panel, and it seems that WinForms is happier to have a textbox focused than a panel.
Well, first of all, can somebody provide expert insight on this matter? And also, if it is indeed possible for the focus to change without explicit order from me (whether user action or programmatic) is it possible to programmatically distinguish the resulting Leave and Enter events? That is, I would like to programmatically counteract Leave/Enter events not caused by myself, but I still want to allow the user to change focus normally as part of work with the GUI.
Yes, that can happen. It is probably a ContainerControl that's messing up your focus, Form is derived from it. A ContainerControl goes hunting for a control to focus when it gets an activation event. It likes nested child controls, it will definitely skip your Panel if it has any controls.
The logic involved in WF to handle focus is very complicated, most of all due to validation. You'd be best off by staying out of trouble and avoid ever giving a Panel the focus. It isn't designed to be a focusable control, it has no way to indicate focus to the user. This is enforced by it having the ControlStyles.Selectable style turned off and the TabStop property set to false so the user can never focus it by tabbing or clicking.
The Enter event won't help, the Panel gets Enter both when it gets the focus or when one of its child controls get the focus. Either by the user tabbing or when you use the Focus() method. You'd have to wait until all focus events are done firing, something you can do with Control.BeginInvoke() or a Timer.
Well, I'm sure that doesn't help much but your problem description is fuzzy. Best way to proceed is to post a sample project that exhibits this behavior to a file sharing service or, as indicated, avoid ever trying to give a parent control the focus.
One thing to keep in mind is many winforms controls cannot be focused at all - winforms provides a CanFocus property to indicate this. Panels have CanFocus set to false, so there is no way to focus directly on a panel without using a derived class that sets that property to true.
I'm working on a custom user control that essentially displays a name value pair (name is on a black background, value on a white). I have my control displaying correctly, even showing up in Designer and on my build page.
What I'd like to do from here is have the ability to right click on the user control and have a menu come up that has a "Copy Value" option, that when selected will copy the value in the "value" part of the user control to the clipboard. What is the best method of approach?
I'm not sure where to start since most of the documentation on user controls I've found deals with displaying the control, not necessarily interacting with it. Additionally, since I'm still learning C#, I might have left out an important part of my problem in this question, so please point that out if it's the case.
I'm using Visual Studio 2008 (if that matters).
Examine the ContextMenu control and the ContextMenu property of other controls. By assigning a ContextMenu control to the ContextMeny property of another control, you will have the right-click->popup menu wiring done for you. Then you only need to implement the click event of the different menu items in the context menu.
Then you can use the Clipboard.SetText (as suggested by BFree) to set the desired value to the clipboard.
Add a ContextMenu to the control. The, hook into the MouseClick (or MouseDown, whichever works better) event and if it's a Right-Click, then call show on the ContextMenu (there are a few overloads, try to mess with them see which works best for you). Then, in the click event of your context menu, just call Clipboard.SetText(...) to set the value to the clipboard.