I am trying to implement very simple text formatting functionality for a RichTextBox in WPF. This just consists of a few bold, italic, etc ToggleButtons just above the RichTextBox. See image below, but ignore the top TextBox - the RichTextBox is the bigger one at the bottom.
Toggling formatting for either a selection or at the caret position (for text that will be typed in) is not a problem, as I'm doing this:
private void BoldButton_Checked(object sender, RoutedEventArgs e)
{
this.SetSelectionBold(true);
}
private void BoldButton_Unchecked(object sender, RoutedEventArgs e)
{
this.SetSelectionBold(false);
}
private void SetSelectionBold(bool isBold)
{
var selection = this.RichText.Selection;
if (selection != null)
{
selection.ApplyPropertyValue(TextElement.FontWeightProperty, isBold ? FontWeights.Bold : FontWeights.Normal);
}
}
However, if the user moves the caret somewhere else (e.g. from bold text to normal text) then I'd like the ToggleButtons to reflect that state, in much the same way as it works in Word. Is it possible to detect when the caret position changes, and take action accordingly?
Hook yourself into SelectionChanged event and get current caret position, and test if the property exists on that selection?
In the event, probably you want something like:
var selection = richTextBox.Selection;
if(selection != null)
{
if(selection.GetPropertyValue(TextElement.FontWeightProperty) == FontWeights.Bold)
// todo; enable your button
}
If that event is not triggered by caret positioning(the document doesn't say anything about that),
you probably need to inherit from RichTextBox and override OnSelectionChanged, after that you need to actually generate your own Caret, eg:
var currentCaretPlusOne = new TextRange(richTextBox.CaretPosition,
richTextBox.CaretPosition+1);
if(currentCaretPlusOne != null)
{
if(currentCaretPlusOne.GetPropertyValue(TextElement.FontWeightProperty)
== FontWeights.Bold)
// todo; enable your button
}
Related
I'm writing a .NET 4.5 C# / WPF app where I must specifically detect if a ComboBox is in edit mode. In other words, I need to know only if the mouse cursor is active and blinking in the editable portion of the ComboBox, and the ComboBox is ready for input from the user's typing on the keyboard.
I've tried "TextBoxBase.GotFocus", "TextBoxBase.GotKeyboardFocus", etc.
These events fire even when a user simply clicks on the ComboBox, which doesn't make any sense (why does a "GotKeyboardFocus" event fire even when I haven't even touched the keyboard?).
Anyways, how can I detect ONLY when the mouse cursor is active and blinking in the editable portion of the ComboBox, and the ComboBox is ready for input from the user's typing on the keyboard?
Got it...
void cmbMyComboBox_Loaded(object sender, RoutedEventArgs e)
{
var obj = (ComboBox)sender;
if (obj != null)
{
var t = (TextBox)obj.Template.FindName("PART_EditableTextBox", obj);
if (t != null)
{
t.MaxLength = 16;
t.GotFocus += (s, a) => { MyFunction(); } };
t.LostFocus += (s, a) => { MyOtherFunction(); } };
}
}
}
I have a control that is similar to a Popup or Menu. I want to display it and when the user clicks outside the bounds of the box, have it hide itself. I've used Mouse.Capture(this, CaptureMode.SubTree) as well as re-acquired the capture the same way Menu/Popup do in OnLostMouseCapture.
When the user clicks outside the bounds of the control, I release the mouse capture in OnPreviewMouseDown. I don't set e.Handled to true. The mouse click will make it to other controls on the main UI, but not to the close button (Red X) for the window. It requires 2 clicks to close the app.
Is there a way to tell WPF to restart the mouse click, or to send a repeated mouse click event?
Here's my code. Note I renamed it to MainMenuControl - I'm not building a Menu, so Menu/MenuItem and Popup aren't options.
public class MainMenuControl : Control
{
static MainMenuControl()
{
DefaultStyleKeyProperty.OverrideMetadata(typeof(MainMenuControl), new FrameworkPropertyMetadata(typeof(MainMenuControl)));
}
public MainMenuControl()
{
this.Loaded += new RoutedEventHandler(MainMenuControl_Loaded);
Mouse.AddPreviewMouseDownOutsideCapturedElementHandler(this, OnPreviewMouseDownOutsideCapturedElementHandler);
}
void MainMenuControl_Loaded(object sender, RoutedEventArgs e)
{
this.IsVisibleChanged += new DependencyPropertyChangedEventHandler(MainMenuControl_IsVisibleChanged);
}
void MainMenuControl_IsVisibleChanged(object sender, DependencyPropertyChangedEventArgs e)
{
if (this.IsVisible)
{
Mouse.Capture(this, CaptureMode.SubTree);
Debug.WriteLine("Mouse.Capture");
}
}
// I was doing this in OnPreviewMouseDown, but changing to this didn't have any effect
private void OnPreviewMouseDownOutsideCapturedElementHandler(object sender, MouseButtonEventArgs e)
{
Debug.WriteLine("OnPreviewMouseDownOutsideCapturedElementHandler");
if (!this.IsMouseInBounds())
{
if (Mouse.Captured == this)
{
Mouse.Capture(this, CaptureMode.None);
Debug.WriteLine("Mouse.Capture released");
}
Debug.WriteLine("Close Menu");
}
}
protected override void OnLostMouseCapture(MouseEventArgs e)
{
base.OnLostMouseCapture(e);
Debug.WriteLine("OnLostMouseCapture");
MainMenuControl reference = e.Source as MainMenuControl;
if (Mouse.Captured != reference)
{
if (e.OriginalSource == reference)
{
if ((Mouse.Captured == null) || (!reference.IsAncestorOf(Mouse.Captured as DependencyObject)))
{
//TODO: Close
Debug.WriteLine("Close Menu");
}
}
// if a child caused use to lose the capture, then recapture.
else if (reference.IsAncestorOf(e.OriginalSource as DependencyObject))
{
if (Mouse.Captured == null)
{
Mouse.Capture(reference, CaptureMode.SubTree);
Debug.WriteLine("Mouse.Capture");
e.Handled = true;
}
}
else
{
//TODO: Close
Debug.WriteLine("Close Menu");
}
}
}
private bool IsMouseInBounds()
{
Point point = Mouse.GetPosition(this);
Rect bounds = new Rect(0, 0, this.Width, this.Height);
return bounds.Contains(point);
}
}
The problem is that the mouse handling you are talking about is outside the WPF eventing system and part of the operating system so we're really talking about two fairly different mouse message queues that interact well enough most of the time but in these edge case we see that the interoperability is not perfect.
You could try to generate Win32 mouse messages or send your own window a close message but all those approaches are hacks. Since popups and menus exhibit exactly the same symptoms you describe, it doesn't seem like there is going to be an easy to way to accomplish what you want as you've described it.
Instead, I suggest that you consider giving up the mouse capture when the mouse leaves the north client area of the window or some other heuristic such as a specified distance from the control. I know this is probably not ideal but it might be a satisfactory compromise if you want the close button to work badly enough.
I want to add a simple (at least I thought it was) behaviour to my WPF TextBox.
When the user presses Escape I want the TextBox he is editing to have the text it had when the user started editing, AND I want to remove the focus from the TextBox.
I don't have any problem setting the text for the value it had in the beginning of the edit.
The problem is to remove the focus of the element. I don't want to move the focus to any other component, I just want the TextBox to lose focus. Will I have to have an invisible element to set the focus so my TextBox can lose focus?
in .NET Framework 4 just Keyboard.ClearFocus();
The code I have been using :
// Move to a parent that can take focus
FrameworkElement parent = (FrameworkElement)textBox.Parent;
while (parent != null && parent is IInputElement && !((IInputElement)parent).Focusable)
{
parent = (FrameworkElement)parent.Parent;
}
DependencyObject scope = FocusManager.GetFocusScope(textBox);
FocusManager.SetFocusedElement(scope, parent as IInputElement);
Since none of the above answers worked for me and the accepted answer does work only for a keyboard focus, I came to the following approach:
// Kill logical focus
FocusManager.SetFocusedElement(FocusManager.GetFocusScope(textBox), null);
// Kill keyboard focus
Keyboard.ClearFocus();
Kills both, logical as well as the keyboard focus.
A bit late to the party, but it was helpful to me so here it goes.
Since .Net 3.0, FrameworkElement has a MoveFocus function which did the trick for me.
You can set the focus to a focusable ancestor. This code will work even if the textbox is inside a template with no focusable ancestors inside that same template:
DependencyObject ancestor = textbox.Parent;
while (ancestor != null)
{
var element = ancestor as UIElement;
if (element != null && element.Focusable)
{
element.Focus();
break;
}
ancestor = VisualTreeHelper.GetParent(ancestor);
}
AFAIK, it is not possible to completely remove the focus. Something in your Window will always have the focus.
For me, it's quite tricky, especially when using with LostFocus binding.
However, my workaround is to add an empty label and focus on it.
<Label Name="ResetFocusArea" Focusable="True" FocusVisualStyle="{x:Null}" />
...
OnKeyDown(object sender, RoutedEventArgs e)
{
//if is Esc
ResetFocusArea.Focus();
}
Using LPL's answer worked for me, but it would also make me unable to select any options in dropdown menues. To combat this, I added a check to see if the focused element was a textbox.
Doing the same check for when pressing enter, my final code looked like this:
public Menu()
{
InitializeComponent();
this.PreviewMouseDown += PreviewMouseDownEventHandler;
this.KeyDown += WindowKeyDownHandler;
}
void ClearFocus()
{
UIElement elementWithFocus = Keyboard.FocusedElement as UIElement;
if (elementWithFocus is System.Windows.Controls.TextBox tb)
{
if (Keyboard.FocusedElement != null)
{
Keyboard.FocusedElement.RaiseEvent(new RoutedEventArgs(UIElement.LostFocusEvent));
Keyboard.ClearFocus();
}
}
}
private void PreviewMouseDownEventHandler(object sender, MouseButtonEventArgs e)
{
ClearFocus();
}
private void WindowKeyDownHandler(object sender, System.Windows.Input.KeyEventArgs e)
{
if (e.Key == Key.Enter)
{
ClearFocus();
}
}
With this, I didn't need to add a focuslost to every textbox, and it can easily extend to other elements without breaking compatability with other parts of the program.
In Windows Phone Development, I just did Focus() or this.Focus() in the PhoneApplicationPage and it worked like a charm.
My answer does not adress the above question directly, however, I feel that the wording of it has caused it to become "The Question" about programmatically getting rid of focus. A common scenario where this is needed is for the user to be able to clear focus upon left-clicking the background of a root control, like window.
So, to achieve this, you can create an Attached Behavior that will switch focus to a dynamically created control (in my case, an empty label). It is preferrable to use this behavior on the highest-level elements like windows, as it iterates through it's children to find a panel it can add a dummy label to.
public class LoseFocusOnLeftClick : Behavior<FrameworkElement>
{
private readonly MouseBinding _leftClick;
private readonly Label _emptyControl = new Label() { Focusable = true, HorizontalAlignment = HorizontalAlignment.Left, VerticalAlignment = VerticalAlignment.Top };
public LoseFocusOnLeftClick()
{
_leftClick = new MouseBinding(new RelayCommand(LoseFocus), new MouseGesture(MouseAction.LeftClick));
}
protected override void OnAttached()
{
AssociatedObject.InputBindings.Add(_leftClick);
AssociatedObject.Loaded += AssociatedObject_Loaded;
}
protected override void OnDetaching()
{
AssociatedObject.InputBindings.Remove(_leftClick);
AssociatedObject.Loaded -= AssociatedObject_Loaded;
}
private void AssociatedObject_Loaded(object sender, RoutedEventArgs e)
{
AssociatedObject.Loaded -= AssociatedObject_Loaded;
AttachEmptyControl();
}
private void AttachEmptyControl()
{
DependencyObject currentElement = AssociatedObject;
while (!(currentElement is Panel))
{
currentElement = VisualTreeHelper.GetChild(currentElement, 0);
}
((Panel)currentElement).Children.Add(_emptyControl);
}
private void LoseFocus()
{
_emptyControl.Focus();
}
}
If you want to remove focus from a certain TextBox, just add this line..
textBox.Focusable = false;
Is there a way to make some of the items in a ListBox readonly/disabled so they can't be selected? Or are there any similar controls to ListBox to provide this functionality?
ListBox doesn't have support for that. You can bolt something on, you could deselect a selected item. Here's a silly example that prevents even-numbered items from being selected:
private void listBox1_SelectedIndexChanged(object sender, EventArgs e) {
for (int ix = listBox1.SelectedIndices.Count - 1; ix >= 0; ix--) {
if (listBox1.SelectedIndices[ix] % 2 != 0)
listBox1.SelectedIndices.Remove(listBox1.SelectedIndices[ix]);
}
}
But the flicker is quite noticeable and it messes up keyboard navigation. You can get better results by using CheckedListBox, you can prevent the user from checking the box for an item:
private void checkedListBox1_ItemCheck(object sender, ItemCheckEventArgs e) {
if (e.Index % 2 != 0) e.NewValue = CheckState.Unchecked;
}
But now you cannot override drawing to make it look obvious to the user that the item isn't selectable. No great solutions here, it is far simpler to just not display items in the box that shouldn't be selectable.
#Hans solution causing that the item id selected for a short time and then selection disappearing. I don't like that - this can be confusing for the enduser.
I prefer to hide some edit option buttons for the item that should be disabled:
if (lbSystemUsers.Items.Count > 0 && lbSystemUsers.SelectedIndices.Count > 0)
if (((RemoteSystemUserListEntity)lbSystemUsers.SelectedItem).Value == appLogin)
{
bSystemUsersDelete.Visible = false;
bSystemUsersEdit.Visible = false;
}
else
{
bSystemUsersDelete.Visible = true;
bSystemUsersEdit.Visible = true;
}
Here is the list that lists the users and disallow to edit user that is actually logged in to the edit panel.
ListBox doesn't have a ReadOnly (or similar) property, but you can make a custom ListBox control. Here's a solution that worked pretty well for me:
https://ajeethtechnotes.blogspot.com/2009/02/readonly-listbox.html
public class ReadOnlyListBox : ListBox
{
private bool _readOnly = false;
public bool ReadOnly
{
get { return _readOnly; }
set { _readOnly = value; }
}
protected override void DefWndProc(ref Message m)
{
// If ReadOnly is set to true, then block any messages
// to the selection area from the mouse or keyboard.
// Let all other messages pass through to the
// Windows default implementation of DefWndProc.
if (!_readOnly || ((m.Msg <= 0x0200 || m.Msg >= 0x020E)
&& (m.Msg <= 0x0100 || m.Msg >= 0x0109)
&& m.Msg != 0x2111
&& m.Msg != 0x87))
{
base.DefWndProc(ref m);
}
}
}
I know this is old thread, but i'll post a workaround for other readers in future.
listBox.Enabled = false;
listBox.BackColor = Color.LightGray;
This will change background color of list box to Light Gray. So this is not builtin "native way" to do it, but at least gives user some feedback that he is not supposed to / can't edit that field.
To get read-only behaviour I have MyCBLLocked, a boolean associated with the MyCBL checkbox list control, and on the CheckItem event I do:
private void MyCBL_ItemCheck(object sender, ItemCheckEventArgs e)
{
if (MyCBLLocked)
e.NewValue = e.CurrentValue;
}
So instead of
MyCBL.Enabled = false;
I use
MyCBLLocked = true;
and the user can scroll through the many selections but not mess things up with changes.
Here is the deal: I have a RichTextBox control and it works fine. The problem is that there is a button "Insert Current DateTime" which adds/injects the current datetime into the RichTextBox. The user can enter the datetime anywhere where the caret is pointing. This involves complicated string manipulation and stuff.
Any ideas how to get the current caret position. Whenever I get RichTextBox.CaretPositon it seems it is pointing to the start of the RichTextBox and not where the actual caret is.
UPDATE 1:
The date time button click code:
private void DateTimeStampButton_Click(object sender, RoutedEventArgs e)
{
//TextRange tr = new TextRange(textBox.Selection.Start, textBox.Selection.End);
var tr = new TextRange(textBox.Document.ContentStart, textBox.Document.ContentEnd);
if(tr.Text.Length == 2)
{
if(tr.Text == "\r\n")
{
tr.Text = tr.Text.TrimStart(new[] { '\r', '\n' });
}
}
textBox.CaretPosition.InsertTextInRun(DateTime.Now.ToShortDateString() + " " + DateTime.Now.ToShortTimeString() + ": ");
DateTimeStampButton.Focusable = false;
}
private void SharpRichTextBox_LostFocus(object sender, RoutedEventArgs e)
{
SetValue(TextProperty, Text);
var binding = BindingOperations.GetBinding(this, TextProperty);
if (binding == null) return;
if (binding.UpdateSourceTrigger == UpdateSourceTrigger.Default || binding.UpdateSourceTrigger == UpdateSourceTrigger.LostFocus)
{
// if (TextProperty != null) BindingOperations.GetBindingExpression(this, TextProperty).UpdateSource();
}
}
public string Text
{
get
{
var newValue = new TextRange(Document.ContentStart, Document.ContentEnd).Text.RemoveNewLineAndReturn();
return newValue;
}
set
{
if (!String.IsNullOrEmpty(value))
{
SetValue(TextProperty, value.RemoveNewLineAndReturn());
Document.Blocks.Clear();
Document.Blocks.Add(new Paragraph(new Run(value)));
OnPropertyChanged("Text");
}
}
}
UPDATE 2:
Turned out the problem was with the DateTime button being Focusable. I turned it to be not focusable and it worked as expected. When focus was lost on the RichTextBox it was resetting the caret position. It happened only once since in the code the btn_DateTime was dynamically being set as Focusable = false. I placed Focusable = false in XAML and everything worked fine from the start.
I'm using this code to successfully do what you are attempting:
private void insertNowButton_Click(object sender, RoutedEventArgs e)
{
//NOTE: The caret position does not change.
richTextBox1.CaretPosition.InsertTextInRun(DateTime.Now.ToString());
}
EDIT: Addressing Update 1
private void DateTimeStampButton_Click(object sender, RoutedEventArgs e)
{
var tr = new TextRange(textBox.Document.ContentStart, textBox.Document.ContentEnd);
if (tr.Text.Length == 2)
{
if (tr.Text == "\r\n")
{
tr.Text = tr.Text.TrimStart(new[] { '\r', '\n' });
}
}
/* Changing the text is the only way I can get the date to insert at the beginning */
tr.Text = "I need a beer at ";
textBox.CaretPosition.InsertTextInRun(DateTime.Now.ToString());
}
It looks like SetValue is changing the text so based on my test that actually changing the text resets the caret, I would agree with you that SetValue is causing the problem...
I tried this solution with WPFToolkit.Extended RichTextBox and it didn't work for me.
However I found another one and thought it would be good to post it in here in case someone else could use it.
My problem was also that the after I clicked a button that is supposed to append text at the caret location, it instead adds it at the beginning of the RichTextBox.
So The solution I found is similar to the one in here -
RichTextBox CaretPosition physical location
Instead of using CaretPosition I used RichTextBox.Selection.Start.InsertTextInRun("SomeText").
It considered the selection's start as the caret position even though no selection was made and therefore was good enough for me.
I hope someone will find this useful :)
This worked for me:
private void InsertText(String text, RichTextBox rtb)
{
rtb.CaretPosition = rtb.CaretPosition.GetPositionAtOffset(0, LogicalDirection.Forward);
rtb.CaretPosition.InsertTextInRun(text);
}
I found the code here:
How do I move the caret a certain number of positions in a WPF RichTextBox?