Form only saving when inputs lost focus - c#

I'm using a form (FormView) with databinding (ObjectDataSource) and all my input fields are bound by using '<%# Bind("field") %>'.
Everything works fine, but I have two problems (which I found various hints about like using this.Validate() or .EndEdit() - but none seem to work):
Entries are only saved after leaving the input field so it looses focus
Let's say I have a textbox with an ID of Name and enter "George". When I would tab to the next textbox or when I click somewhere else and click save - everything is saved. But when I keep the focus in the textbox the value is not saved. Why is this happening? What magic can I use to circumvent this (JavaScript to the rescue?).
I set a textbox's field value (element.value) via Javascript (upon selecting something in a combobox).
The same problem as above applies, only when I give the textbox focus and tab out the value is saved. This creates the problem that I only want the user to choose something in the combobox (the textbox is updated accordingly) and move on - I don't want the user to click into the textbox afterwards and tab out again.
Edit:
The second problem I resolved now by setting the focus onto my textbox via Javascript (textbox.focus();) and right after set the focus back to the combobox (combobox.focus();) and that does the trick - this seems fairly hackish to me, doesn't it?
I'm assuming this is fairly common, but my mighty Google fu hasn't help me find a simple solution.

A similar issue can crop up in Winforms development when working with DataGridView controls. I typically attach some logic to the submit button's Click event to cause the DataGridView to validate. I suspect a similar solution would work for you here.

Related

How to avoid losing the input focus on an HTML element inside a WebView?

I'm currently trying to build a touch keyboard to be used with an UWP app. One of the solutions I came up with was to use a brokered component to call SendKeys funcitons with buttons (IsTabStop being set to false and ClickMode to Press to prevent any loss of focus from the input controls). So far, everything works (tested it on TextBoxes without any trouble).
The problem: I'm encountering some issues using the WebView control : when I click a button, the WebView keeps the focus, as expected; however, the DOM elements (such as HTML's <input> markup) lose the input focus (while still being visually selected).
I found a way to solve this by resetting the focus on the webview; but that uncovered another issue. Let's say the input element is set to select all of it's content (the string) whenever it is focused. Then, each time I click one of my buttons, the content is selected and replaced by the new letter I sent to the WebView.
So, my question is, is there any way to avoid losing the focus of the DOM object when clicking on a XAML button?
NB : I do know about the InputPane, but I can't use it for this app (due to some restrictions on the client side). Also, let me know if something is unclear, and I'll edit asap.
NB2 : I have absolutely no access to the source code of the pages that will be displayed by the WebView, nor can I rely on the presence of a specific element.
The Anniversary Update introduced a new property FrameworkElement.AllowFocusOnInteraction for this scenario. Set it to false on your Button and the Button won't take the focus when it is clicked. The focus will stay on the WebView and the selection shouldn't get cleared (if not there's something else going on as well).
Prior to this there wasn't a good solution. The least bad I've seen was to call WebView.Focus() in the Button.Click handler to return the focus, then wait for the focus events to complete before proceeding in the Click hander.
If you need to target earlier systems than the Anniversary Update then you'll need to set AllowFocusOnInteraction from code after checking that it exists with ApiInformation.IsPropertyPresent . You can't do this directly in Xaml, but you can wrap the check in an attached property which can be called from Xaml. See my blog entry ComboBox on a Flyout attached to an AppBarButton loses mouse input on 1607 for sample code.

How do I display the value in the Textbox

How do I display Price value($) in textbox next to a label when user checks the radio button, select one of item from listBox, and then clicks the button?
Is there way to do it on the form1.cs[Design] using the properties? Or do I need to set them up in code level?
listBox item example
EDIT: Solved this in Code-level.
I don't think you can do it without any code.
Also I'd recommend you to check out this page - just a few simple rules can make your chances to get a good answer on this site much better.
And there is not much of coding needed to solve your problem. Take a look on the Events tab in Property view in form designer. A few event handlers to process user input and some fields inside your class to store the data - I assume it is not some serious business app you're dealing with, so all the code you need for this to work would be like 20 lines tops -)

C# How to commit a TextBox?

In a form, I have a TextBox Binding an Object on its member property "Title". Along with it is a "Save" button to test the binding.
Seems like the underlying object property does not get updated unless the textbox loses focus. But there no form.ActiveControl.Blur() for use. Besides, this does not seem like a sound hack.
Anyway to do this better? Thanks.
EDIT: Sorry for not being clear. My question is in the title: "How to commit a TextBox". I use the term "commit" from the DataGridView commit and BindingSource commit. And it's in WinForms. (Have never worked with WPF, so it didn't occur to me. Sorry).
The actual scenario I have is I have a bunch of TextBox binded to property of a single Object. The user enters values in all the TextBox and when the user clicks save (toolbar button), the last TextBox is still in focus (or in editing mode) hence the save will not capture the last value in the last textbox.
I want to find the correct way to "commit" the textbox value just before saving.
Thanks.
Since the question has been updated to indicate this is WinForms, you'll need to handle things a little differently than if this were a WPF application. Fortunately, it turns out that the solution is very simple.
Whenever the user clicks on the "Save" button (so, say, in your Save button's Click event handler), you need to call the EndEdit method on your BindingSource. This will cause all pending changes to be committed to the underlying data source, exactly what you were hoping to accomplish.
Also see the relevant documentation on MSDN for more details.
Sounds like WPF from the problem description..
You want to change the binding so that it updates when the property value changes instead of when the textbox loses focus (which is the default when binding to TextBox.Text). You can do this by setting the UpdateSourceTrigger property on your binding:
<TextBox Text="{Binding UpdateSourceTrigger=PropertyChanged}"/>

C# UserControl Validation

I have a UserControl with a Tab Control containing three tabs. Within the tabs are multiple controls - Datetimepickers, textboxes, comboboxes.
There is also a Save button which when clicked, calls this.ValidateChildren(ValidationConstraints.Enabled) Now, I click save and a geniune validation error occurs. I correct the error and then click save again - valdiation errors occur on comboboxes on a different tab. If I navigate to this tab and click save, everything works fine. How can this be? I haven't changed any values in the comboboxes so how can the fail validation then pass validation?
The comboboxes are bound to a dataset with their selectedValue and Text set. I just don't understand what is happening here.
This behaviour also occurs for some textboxes too. The validation rule is that they have to be a decimal - the default value is zero, which is allowed. The same thing happens, they fail validation the first time - I make no changes, click save again and they pass validation.
EDIT:
The error is not a Framework error - the error is the one I provide during my validation routine. e.g Select a valid drop down option.
I stepped through the process and the sometimes the combobox values are the default values other times the selectedvalue is the default but the text is null. I don't see how this can happen if I'm not changing anything in the combobox.
If you need any further information please let me know
thanks
Barry
The following is a quote from MSDN:
"Controls contained in a TabPage are not created until the tab page is shown, and any data bindings in these controls are not activated until the tab page is shown."
So I'm guessing that if before you press save the first time, you make sure that you've clicked on each tab at least once, it'll work as expected, but if you don't look at all tabs before saving, it fails?
Have you checked that the default value is not null ?

Override tab behavior in WinForms

I have a UserControl that consists of three TextBoxes. On a form I can have one or more or my UserControl. I want to implement my own tab behavior so if the user presses Tab in the second TextBox I should only move to the third TextBox if the the second TextBox has anything entered. If nothing is entered in the second TextBox the next control of the form should get focus as per the normal tab behavior. If the user hasn't entered anything in the first or second TextBox and the presses tab there is this special case where a control on the form should be skipped.
By using the ProcessDialogKey I have managed to get it work kind of ok but I still have one problem. My question is if there is a way to detect how a WinForms control got focus since I would also like to know if the my UserControl got focus from a Tab or Shift-Tab and then do my weird stuff but if the user clicks the control I don't want to do anything special.
As a general rule, I would say overriding the standard behavior of the TAB key would be a bad idea. Maybe you can do something like disabling the 3rd text box until a valid entry is made in the 2nd text box.
Now, having said this, I've also broken this rule at the request of the customer. We made the enter key function like the tab key, where the enter key would save the value in a text field, and advance the cursor to the next field.
I don't think there's a built-in way that you could do it. All of the WinForms focus events (GotFocus,LostFocus,Enter,Leave) are called with empty EventArgs parameters, which will not give you any additional information.
Personally, I would disable the third textbox, as Rob Thomas said. If you're determined to do this, though, it wouldn't be difficult to set up a manual (read: hackish) solution. Once the tab key is pressed (if the focus is on the second textbox), set a variable inside your form. If the next object focused is then the third textbox, then you know exactly how it happened.
The reason for this odd tab behavior is all about speed in the input process. It was really good to get some input, I hadn't thought about disabling a textbox but that could actually work. But using the Enter key to accept the input hadn't even crossed my mind. That will work so much better. The user can enter the numbers and then press enter to accept the input and the next possible textbox will be the active one. It's like having the cake and eating it too, The speed factor is there since when using the enter key no unnecessary tabing must be done to get to the correct field and using the enter key next to the numeric keyboard makes it really smooth.
Thanks for the input!
I agree with DannySmurf. Messing with the tab order might give you hell later on if the requirements for the application change.
Another thing that you could do is to implement some kind of wizard for the user to go through.
Better than disabling controls, try monkeying around with TabStop - if this is false, the control will be simply skipped when tabbing.
I'd also suggest that the Changed event of the TextBox is the place to be updating TabStop on the other controls.
I've done something similar to this with a login control, where users could enter either a username or an email address (in separate fields), plus their password, and tabStop is what I used to get the job done.

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