I have a handler for the TextBox's PreviewLostKeyboardFocus event. It fires when I leave the TextBox using the keyboard (Tab key) or the mouse (by clicking on another TextBox on the form).
The handler takes a KeyboardFocusChangedEventArgs, which has a property named KeyboardDevice, which isn't null in either scenario (I was hoping to find null here when using the mouse).
Question: How can I tell whether a user used the keyboard or the mouse to leave a WPF TextBox?
The e.KeyboardDevice.GetKeyStates(Key.Tab) (where e is of type KeyboardFocusChangedEventArgs) reports:
None (when mouse was used to change focus)
Down, Toggled (when TAB was use to leave the TextBox)
Would that work for you?
Related
I'm new on C#, I made a button which makes appear another button and I want to remove the click event of this new one and change it into an enter(key) event.
Code1
Code2
When the button appears it only works when I click it but no when I press Enter.
As to your question, https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.control.enter?view=net-5.0
The enter event is for when keyboard or mouse enter the control (button in this case).
From the sounds of your question, you are wanting to click the button when the 'Enter' key is pressed.
If this is WinForms, then you might actually want a property on the parent form called 'AcceptButton' (https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.form.acceptbutton?view=net-5.0). This will make it so anytime the Enter key is hit (with the exception of controls such as a RichTextBox that accepts the return key) that button will be clicked (course you still need the button click event for the button).
Although you seem to be doing something weird in your example code image, so I'm not sure that's the correct solution for it. Instead, you need to look at maybe the Keyboard events, such as KeyPress (https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.control.keypress?view=net-5.0). There are several: KeyDown, KeyPress, KeyUp, and PreviewKeyDown.
Note these events require Keyboard focus on the control in question. So if add them to the button you are creating in your example code, then that button will need keyboard focus to receive the keyboard events.
Also, just FYI, if a button has keyboard focus, by default the SpaceBar will click that button for you, while the Enter key is generally reserved for clicking the Form's AcceptButton.
I am working with a TextBox, and need to fire some logic when the textbox has lost focus.
My problem is twofold:
The Leave event is firing on every keypress for some reason, meaning the logic is run with every keypress when it should not.
When using the Focused property of the Textbox as a double-check, simply exiting out if the property is still set, it now works when the user uses the mouse to leave, but not when the user tabs out.
The Focused property of the TextBox in question is False as of when its Leave event fires when the mouse is used to change focus, but it is still True when the Leave event fires due to a Tab keypress. Seriously?
I need a workaround, because the logic firing on every keystroke is causing a problem for users right now that needs to be fixed post-haste.
I created a form with a textbox on it and attached event handler to the leave event of that text box. I then typed a bunch of stuff into said textbox. The event was not raised. I hit tab, the event was raised. I then clicked back in the textbox, typed some more, and then clicked another control and the event was raised.
I'm just saying that something else is interfering with the textbox. I would look into that a little more, or post some code demonstrating the problem.
I am using UltraComboEditior of Infragistics Conrtrols in C# winform application, I want to show a messageBox when UltroComboEditior got focues by MouseClick or KeyBoard Tab button, how can I do it? Any suggestions ? I tried BeforeDropDown but it is called only when we click on arrow button to show drop down list but I am using only drop down with auto complete option set to be true.
UltraComboEditor control has "Enter" event which fires when the control becomes the active control of the form, and this event will fire in both situations - when the control got focus by using your Tab key, and when you are using your mouse.
I hope that this will help you to achieve your goal.
Doesn't it inherit the OnGotFocus event which you can subscribe to?
How can I capture the Keydown event of a form that is not active?
I found references to ProcessKeyDown but I couldn't find any help on that.
Please set KeyPreview of the form to true. First select form and press f4 key, it will open property window and their is KeyPreview and set it to true.
Right cilck on the form and cilck properties, then there will be flash button , it is for events for that object. Find thier Keypress event. just doulbe click on the column corresponding to that event. It will create event for keypress.
For the documentation and help, check this link.
Keypress events are only sent to Controls that have input focus. You can use the Control.HasFocus property to determine whether your Control has focus or not. Use the Control.Focus() method to give your control focus.
You can set a low level keyboard hook using SetWindowsHookEx() to listen for key press events.
If what you want to do is trigger some code in your program upon keys being pressed in the operating system regarding of whether the form is active or not then you can use the method described in this article:
Processing Global Mouse and Keyboard Hooks in C#
Here is a simple example of a program using that library to simulate a virtual mouse by pressing the numeric keys on the numpad.
'1'-'4' and '6'-'9' are directional keys, '5' is left click, '0' is double click.
Program.cs
Form1.cs
Observe that i didn't call the Application.Run(); with a new Form1() parameter so that the application would run but will not be visible on screen. To end the program you have to press CTRL+SHIFT+ESC, go to Processes page and end the process manually.
I have 6 Buttons, labeled "_0" through "_5". I would like for each button to be pressed when the user presses the corresponding number key. Right now, they must press Alt + the corresponding number key.
I can sort of work around this by giving each button an Accelerator, but it's not quite the same thing. With accelerators, as soon as the key is pressed, the button's Clicked signal is triggered. With mnemonics, the button becomes depressed when the key is pressed, and the Clicked signal isn't triggered until the button is released. I prefer this, because it helps the user to see what is happening.
Is there any way I can get the behavior of Mnemonics, but without requiring the Alt key?
You can have the gtk window catch key events with the event mask settings in the window class. I can't be much more specific than that with callbacks and key types, because I use GTKmm (C++ bindings) but the approach should be similar. Basically when you catch the required key event in your window you can call the button press in code. The window has be to selected (in focus) however.