I have a textbox that requires data to be entered in a certain way. I have implemented some cell validating techniques to check the data after it has been entered, but I'd like to provide the user with some information before they enter the data.
To that end, I'd like to add a tooltip to the textbox that pops up when the user enters the toolbox, then exits when they begin to type.
For example I have the following code:
private void YearEdit_Enter(object sender, EventArgs e)
{
ToolTip tt = new ToolTip();
tt.IsBalloon = true;
tt.InitialDelay = 0;
tt.ShowAlways = true;
tt.SetToolTip(YearEdit, "Enter 4 digit year.");
}
This executes when the user enters the textbox, however the tooltip only appears when the mouse hovers over the textbox. Does anyone have any ideas to work around this? I thought that perhaps tt.ShowAlways = true might work, but obviously not.
Hook into the textbox.enter event and use the following code:
private void textBox1_Enter(object sender, EventArgs e)
{
TextBox TB = (TextBox)sender;
int VisibleTime = 1000; //in milliseconds
ToolTip tt = new ToolTip();
tt.Show("Test ToolTip",TB,0,0,VisibleTime);
}
Play with X/Y values to move it where you want. Visible time is how long until it disappears.
Tooltips only appear when the mouse is still by design.
You could try setting the InitialDelay to 0:
tt.InitialDelay = 0;
But this would still require the mouse to be stationary for an instant.
However there are other approaches. A common way of showing what input is required is to use a watermark (faded text) in the textbox that displays the formatting required until the user starts typing.
If you really want a tooltip then you could either add an information icon (usually an "i") which will show the tooltip when it's hovered over, or implement your own.
It might also work if you break the date into parts (separate day, month, year). This will allow you more control over what the user can enter - the month can become a drop down/combo box so it's always the correct format.
you can show a tooltip also like this:
ToolTip t = new ToolTip();
t.Show("Hello World", textBox1, 1000);
Try this. (based on an answer above)
Add event handlers for all controls that you want to have a ToolTip for. Point all the event handlers to the same method. Then construct you handling method like this
private void procToolTips(object sender, EventArgs e)
{
ToolTip tt = new ToolTip();
Control o = (Control)sender;
if ( o.Name == "label1") {
tt.Show("Lorem ipsum dolor sit ame", o, 1000);
}
}
You should use if ( o.Name == label1.Name) instead of if ( o.Name == "label1"), for if you rename label1, this line will be modified too.
More : if(o.equals(label1))...
Related
I'm trying to find a a way to be able to essentially dynamically generate code based on an input.
For example I could type something like:
int Number = 22;
Button<Number>.Text = "X";
So in this case it would set button22 to have its text be an "X".
And I could change it so that I could input, for example 24 into the program and it would then set button24 to be an "X", instead of setting up a bunch of if statements to cover every potential button press.
For further context I have a Grid of 64 buttons and I need to be able to edit them individually to show to the user which buttons have been pressed, it is possible to do it with a lot of if statements but I thought it might be worth trying to find a more elegant solution.
You could have a list of buttons:
private List<Button> _buttons = new List<Button>();
Populate it like this:
for (int i = 0; i < 10; i++)
{
var b = new Button();
b.Text = $"Button #{i}";
b.Click += HandleButtonClick;
}
And you could even set an event handler on one of its events which doesn't even need to use the list (the sender is the source of the event):
private void HandleButtonClick(object sender, EventArgs e)
{
(sender as Button).Text = "X";
}
Buttons have a Tag property that can be used to hold arbitrary data about a button, this is described for WinForms, WPF and UWP.
Simple usage that is similar to OP's requirement is demonstrated in this SO post
This situation is in a practical sense the very reason that .Tag exists at all in user interface controls pretty much from the birth of c#.
So you do not need to use a custom class for a button, just simply assign your value to the .Tag property on the Button class that you are creating programmatically:
in this example a list is used to create the buttons and separate the creation from the layout, it is not necessary to do this, but may be useful. Instead, you could assign this button to it's parent container and/or set the layout margins or coordinates without keeping a reference to the Button object at all.
If OP updates the post to include implementation examples, we can update this response with more specific and complete code.
private List<Button> _buttons = new List<Button>();
// ... iteration or switching logic
var nextButton = new Button
{
Text = "x",
Tag = 22
};
nextButton.Click += DynamicButton_Click;
_buttons.Add(nextButton);
// ... later push the buttons into the parent container or bind to the UI
Then the button click handler you can access this Tag property:
this is presented from WinForms, the only difference in UWP or WPF is the method signature, change EventArgs to RoutedEventArgs
private void DynamicButton_Click(object sender, EventArgs e)
{
if(int.TryParse((sender as Button).Tag?.ToString(), out int buttonValue))
{
// use buttonValue
Console.Out.WriteLine(buttonValue);
}
else
{
// Otherwise, sender was not a button, or the button did not have an integer tag value
// either way, handle that error state here...
}
}
Using these concepts, once the buttons are created, let's say in some simple grid alignment, you could allow the user to set this Tag value at runtime if you have a TextBox (or other) input field that can be accessed from the code.
I recommend that you use MVVM style bindings for this rather than directly referencing a TextBox control, but this is simply to demonstrate the point.
private void DynamicButton_Click(object sender, EventArgs e)
{
// assign the string value from the ButtonValueTextbox control to this button
string value = this.ButtonValueTextBox.Text;
if(sender is Button button)
{
button.Tag = value;
}
else
{
// Otherwise, sender was not a button
// handle the error state here if you need to...
}
}
Now that each button has a tag, you could easily add logic to maintain unique tag values by iterating through the other buttons and clearing the tag if it was previously assigned to a different button.
Maybe you could keep a List of Button References:
var myButtons = new List<Button>();
myButtons.Add(firstButton);
myButtons.Add(secondButton);
// ... etc
// ... then somewhere else
int number = 3;
myButtons[number].Text = "xxx";
I want to do something like this with windows forms:
Something like tags, but I only want label without colors and "x" value, I just want label with click event, how can I do it without using Telerik? it's not possible to do in datagrid view or something like that? Regards
Tag is a very common .Net property, so the question is bit unclear. But looking at the image and taking a wild guess on what you may want..:
If you want to have the ability to add Labels, let's call them TagLabels during runtime you may want to use a FlowLayoutPanel as their container. It will allow adding more and will take care of the layout no matter what sizes they have.
Example:
To create them we can use a TextBox, which we add to the FLP first. Then we code its PreviewKeyDown event and let the user create a new TagLabel by pressing enter..:
private void textBox1_PreviewKeyDown(object sender, PreviewKeyDownEventArgs e)
{
if (e.KeyCode == Keys.Enter && textBox1.Text != "")
{
Label lbl = new Label {
Text = " " + textBox1.Text, /* some room for the image */
BorderStyle = BorderStyle.Fixed3D,
TextAlign = ContentAlignment.MiddleCenter,
AutoSize = true,
Margin = new Padding(2),
ImageIndex = flowLayoutPanel1.Controls.Count %
imageList1.Images.Count,
ImageList = imageList1,
ImageAlign = ContentAlignment.MiddleLeft,
MinimumSize = new Size(100, 20),
BackColor = Color.LightGoldenrodYellow,
Name = "TagLabel" + (flowLayoutPanel1.Controls.Count)
};
lbl.MouseClick +=lbl_MouseClick ;
flowLayoutPanel1.Controls.Add(lbl);
flowLayoutPanel1.Controls.SetChildIndex(lbl,
flowLayoutPanel1.Controls.Count - 2);
textBox1.Text = "";
}
else
if (e.KeyCode == Keys.Escape)
{
textBox1.Text = "";
}
}
The Click event should be generic for all labels; so we first cast sender to Label and can then code the processing..:
private void lbl_MouseClick(object sender, MouseEventArgs e)
{
Label lbl = sender as Label;
//...
MessageBox.Show(lbl.Name + " : Ouch! You clicked on " + lbl.Text.Trim());
}
This is just a basic piece of code. You can style the labels any way you want and of course also include code for deleting, maybe with a context menu. If those labels shall carry more responsibility, you can and should create a class, probably a Label subclass to hold further data and methods..
I'm also using an ImageList to display images to the left. Do change these details to suit your needs!
Note that there is no reasonable way to add the FLP to an ordinary DataGridView. You may be able to workaround but depending on your needs it may be best to keep them separate. DGVs have Cells and while these can hold special controls this is complicated and will always be restricted by the cells' i.e. the Columns' and the Rows' Size. As an alternative you can check out this example to see how you can insert virtual space to a row to hold a control but neither DGV nor its Cells are containers.
How do I create a control in a windows form application? I want to generate a textbox or a radio button when I select something from a Combobox. I basically want to query my database, and based on the values of the fields, I want to generate a textbox or a radio button. For example, if my query returns a value of "Textbox", I want to generate a textbox on the form in a specified location. How does one accomplish this? Please help.
The easiest way is to create the control manually in code and then add it to the Controls collection. Deciding which control to create depending on some input data (whether it's database query or a value selected from a combobox) is not much different then in any other case. Simple if will do the job. For instance:
private void AddControl(string control)
{
if (control == "Textbox")
{
TextBox tb = new TextBox();
tb.Location = new Point(100, 100);
this.Controls.Add(tb);
}
else if (control == "Radio")
{
RadioButton rb = new RadioButton();
rb.Location = new Point(200, 100);
this.Controls.Add(rb);
}
}
Of course, it's very naive version. But it's only a starting point. I leave to you adding more advanced logic (like dynamically adjusting location, setting up properties of the radio button or the textbox, relying on Type instead of on a simple string, etc.)
The assumption is that you retrieve a string value from the database. For example in form's constructor:
public Form1()
{
InitializeComponent();
string requestedControl = QueryDatabase();
AddControl(requestedControl);
}
I leave to you implementing the method to query the database.
In the question you also mentioned adding a control after selecting it in the combobox. In this case the only difference is that you rely on an event triggered after combobox's selection changed:
private void comboBox1_SelectedValueChanged(object sender, EventArgs e)
{
string res = this.comboBox1.SelectedItem.ToString();
this.AddControl(res);
}
Here you rely on SelectedValueChanged event. Of course, in this case your combobox has to be populated with expected values (here "Radio" and "Textbox"). Also, you have to attach the event handler to the specific event on the combobox. You can do that in designer or by adding in the constructor the following line:
combobox1.SelectedValueChanged += comboBox1_SelectedValueChanged;
Hope that clarifies the issue and sets up some starting point for you to continue from.
I have a class derived from TextBox in C#. I override OnClick method to show a file open dialog. Is it possible to lose focus after that? I don't want the user to be able to edit the text because at a moment the file name might be invalid. I tried to set ReadOnly = true, but one can change the text after selecting the file.
EDIT:
I added the relevant code for this. As it is now the focus will be set to next control from my Form.
class Property : TextBox
class FileSelectTextBox : Property
{
protected override void OnClick(EventArgs e)
{
OpenFileDialog dialog = new OpenFileDialog();
Enabled = false;
if (dialog.ShowDialog(this) == DialogResult.OK)
{
Text = dialog.FileName;
}
Enabled = true;
}
}
You have several options here:
Make the textbox ReadOnly. The textbox will still fire OnClick events but the text won't be editable by the user.
Disable the textbox at the end of your click event -- the disadvantage is that the click event won't fire a second time (which means the user won't be able to change their mind and pick a new file).
Simply set the focus somewhere else at the end of the click event. (someOtherTextBox.Focus())
Edit: Once last suggestion: you may want your file popup to happen in FocusGained rather than OnClick, that way the dialog will still pop up if the user tabs into the control. Of course it's your decision if that behavior is desired or not.
Edit 2: Ignore that last edit. It's a bad suggestion that I didn't think through. (Thanks for the heads up commenter)
set the ReadOnly = true property of the textbox (don't change it at any point of time) and it should work lonely..
and rest of the code goes like this..
protected override void OnClick(EventArgs e)
OpenFileDialog dialog = new OpenFileDialog();
//user can still change/edit some non-existing file/path and click OK, so set the followings
dialog.CheckFileExists = true;
dialog.CheckPathExists = true;
if (dialog.ShowDialog(this) == DialogResult.OK)
{
Text= dialog.FileName;
}
}
I'm using a CheckedListBox control in a small application I'm working on. It's a nice control, but one thing bothers me; I can't set a property so that it only checks the item when I actually check the checkbox.
What's the best way to overcome this?
I've been thinking about getting the position of the mouseclick, relative from the left side of the checkbox. Which works partly, but if I would click on an empty space, close enough to the left the current selected item would still be checked. Any ideas regarding this?
I know this thread's a bit old, but I don't think it's a problem to offer another solution:
private void checkedListBox1_MouseClick(object sender, MouseEventArgs e)
{
if ((e.Button == MouseButtons.Left) & (e.X > 13))
{
this.checkedListBox1.SetItemChecked(this.checkedListBox1.SelectedIndex, !this.checkedListBox1.GetItemChecked(this.checkedListBox1.SelectedIndex));
}
}
(With the value of CheckOnClick = True).
You could use that thingy with the rectangle, but why make it more complex the it needs to.
Well, it is quite ugly, but you could calculate mouse hit coordinates against rectangles of items by hooking on CheckedListBox.MouseDown and CheckedListBox.ItemCheck like the following
/// <summary>
/// In order to control itemcheck changes (blinds double clicking, among other things)
/// </summary>
bool AuthorizeCheck { get; set; }
private void checkedListBox1_ItemCheck(object sender, ItemCheckEventArgs e)
{
if(!AuthorizeCheck)
e.NewValue = e.CurrentValue; //check state change was not through authorized actions
}
private void checkedListBox1_MouseDown(object sender, MouseEventArgs e)
{
Point loc = this.checkedListBox1.PointToClient(Cursor.Position);
for (int i = 0; i < this.checkedListBox1.Items.Count; i++)
{
Rectangle rec = this.checkedListBox1.GetItemRectangle(i);
rec.Width = 16; //checkbox itself has a default width of about 16 pixels
if (rec.Contains(loc))
{
AuthorizeCheck = true;
bool newValue = !this.checkedListBox1.GetItemChecked(i);
this.checkedListBox1.SetItemChecked(i, newValue);//check
AuthorizeCheck = false;
return;
}
}
}
Another solution is to simply use a Treeview.
Set CheckBoxes to true, ShowLines to false, and ShowPlusMinus to false and you have basically the same thing as a CheckedListBox. The items are only checked when the actual CheckBox is clicked.
The CheckedListBox is much more simplistic, but the TreeView offers a lot of options that can potentially be better suited for your program.
I succesfully used this property:
CheckedBoxList.CheckOnClick
https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.checkedlistbox.checkonclick?view=netframework-4.7.2
The text for a checkbox in a CheckedListBox is rendered by default is to place an HTML label after the checkbox input and set the label's "for" attribute to the ID of the checkbox.
When a label is denoting an element that it is "for," clicking on that label tells the browser to focus on that element, which is what you're seeing.
Two options are to render your own list with separate CheckBox controls and text (not as the Text property of the CheckBox, as that does the same thing as the CheckBoxList) if the list is static or to use something like a Repeater if the list is dynamic.
Try this. Declare iLastIndexClicked as a form-level int variable.
private void chklst_MouseClick(object sender, MouseEventArgs e)
{
Point p = chklst.PointToClient(MousePosition);
int i = chklst.IndexFromPoint(p);
if (p.X > 15) { return; } // Body click.
if (chklst.CheckedIndices.Contains(i)){ return; } // If already has focus click anywhere works right.
if (iLastIndexClicked == i) { return; } // native code will check/uncheck
chklst.SetItemChecked(i, true);
iLastIndexClicked = i;
}
Just checking to see if the user clicked in the leftmost 15 pixels of the checked list (the check box area) works at all times except re-checking a currently selected item. Storing the last index and exiting without changing lets the native code handle that properly, trying to set it to checked in that case turns it on and it just turns back off when the "ItemCheck" code runs.