This might be kind of beginner question but I searched and didn't find any clear answer!
The main question is: How to inherit properties of a control (specially FlatStyle) from a base form which doesn't have that control in C#?
Details: I have Form1 inherited from baseForm. baseForm has a Panel and a Label control but no Button. In Form1 I added a button named Button1. How can I change the style of that Button through the baseFrom?
I don't want to create a custom control or redesign the button using rectangles or similar ways, but only change that property for all buttons in my application.
UPDATE: I want all of the buttons to be affected, whether they already exist or just added. Not matter in which -if any- container they are.
In baseForm, you could hook the ControlAdded event on the Panel where the Button is to be added, and style appropiately via code. This will work for every form inherited from baseForm.
For example (in baseForm)
public partial class BaseForm : Form
{
public BaseForm()
{
InitializeComponent();
// "myPanel" is the panel where the button will be added in inherited forms
myPanel.ControlAdded += myPanel_ControlAdded;
}
private void myPanel_ControlAdded(object sender, ControlEventArgs e)
{
var button = e.Control as Button;
if (button != null)
{
button.FlatStyle = FlatStyle.Flat;
button.ForeColor = Color.Red;
}
}
}
Just made a really quick test... it works even in design mode:
As an alternative, if you are going to use heavily styled buttons everywhere in your application, you may consider creating a custom control inheriting from Button, and assign the properties there, like:
public class FlatButton : System.Windows.Forms.Button
{
public FlatButton()
{
FlatStyle = FlatStyle.Flat;
}
}
After building, you will find it in the Toolbox (under "[Your Project's] components" tab), or you can cram it on your own control library (in a different solution) and add it permanently to the Toolbox in Visual Studio.
You would need to make use of Reflection
You can use a LINQ query to do this. This will query everything on the form that is type Button
var c = from controls in this.Controls.OfType<Button>()
select controls;
foreach(var control in c)
control.FlatStyle = FlatStyle.Flat;
Related
I have a Windows Forms App.
I created a custom UserControl which extends Panel.
Inside one of my Forms, there is a button which should open that panel when clicked.
However, after clicking, I still don't see the panel displayed on the form.
Form code
public partial class IngredientMenu : Form
{
public IngredientMenu()
{
InitializeComponent();
}
private void btnOpenRegisterBasePanel_Click(object sender, EventArgs e)
{
BaseIngredientPanel baseIngredientPanel = new BaseIngredientPanel();
baseIngredientPanel.Location = new Point(257, 63);
baseIngredientPanel.Show();
baseIngredientPanel.BringToFront();
Console.WriteLine("panel should open");
Console.WriteLine(baseIngredientPanel.Visible);
Console.WriteLine(baseIngredientPanel.Location);
}
}
Panel code
public partial class BaseIngredientPanel : UserControl
{
public BaseIngredientPanel()
{
InitializeComponent();
}
private void btnRegisterBaseIngredient_Click(object sender, EventArgs e)
{
IngredientContext ingredientContext = new IngredientContext();
if (ingredientContext.RegisterIngredient(txtName, txtUnit, lblBaseIngredientNameValidation, lblBaseIngredientUnitValidation))
{
MessageBox.Show("Ingredient Registered."
, "Success", MessageBoxButtons.OK, MessageBoxIcon.Information);
txtName.Text = "";
txtUnit.Text = "";
}
else
{
MessageBox.Show("There are errors in the form fields."
, "ERROR", MessageBoxButtons.OK, MessageBoxIcon.Error);
}
}
private void BaseIngredientPanel_Load(object sender, EventArgs e)
{
Console.WriteLine("I AM OPEN");
}
}
Additionally, the "I AM OPEN" message never appears, even after clicking, so it seems like in general it's not even loading the control.
How can I make the panel open after clicking a button? I'd rather not manually drag a panel into the designer since I need to have like 5 panels and designer is just gonna try to box them like a russian doll.
All UI controls need to have a parent to whom they belong via the Controls.Add() method.
The parent can be a Form or other controls (not all will accept children). e.g. Your panel can be the parent of textboxes, comboboxes, labels, etc.
private void btnOpenRegisterBasePanel_Click(object sender, EventArgs e)
{
BaseIngredientPanel baseIngredientPanel = new BaseIngredientPanel();
baseIngredientPanel.Location = new Point(257, 63);
//Add user panel to form.
this.Controls.Add(baseIngredientPanel);
//You will probably not need these two rows any more. Try it out! But make sure your usercontrol has Visible = true.
baseIngredientPanel.Show();
baseIngredientPanel.BringToFront();
}
Edit:
to answer your questions in the comment below
If you need to make many UI changes at the same time then it is also best to use this.SuspendLayout() and this.ResumeLayout() to temporarily suspend the UI logic. This will help with performance in such cases. See https://learn.microsoft.com/en-us/dotnet/api/system.windows.forms.control.suspendlayout?view=windowsdesktop-5.0 for more details
If you will need to remove the controls at some stage after adding them then you have two options.
Create a separate List<BaseIngredientPanel> to (also) store your
controls when adding them to the form. This use this list to find
and remove them via this.Controls.Remove() method
Give your BaseIngredientPanel a unique Name when creating it, and
use this to find and remove the control via the
this.Controls.Remove() method. All Controls already have a Name property so you can use this.
If you want to show a Form, the class should be derived from Form. Your BaseIngredientPanel is not a Form, it is a UserControl.
UserControls are similar to other Controls like Buttons, ComboBoxes, Menus, DataGridViews, etc. Usually you use Visual Studio Designer to show them on a Form. In rare occassions you do this programmatically.
I created a custom UserControl which extends Panel.
What do you really want:
I want to create a special kind of Panel, one that behaves like a standard Panel, with only small differences. Users of my class may use almost all Properties of my special Panel: Derive from class Panel
I want to create a special kind of Panel, one that behaves like a standard Panel. I want to control which methods users of my special Panel can call: Create a class derived from UserControl and put a Panel on it.
I want to create a Form, on which I want to put a Panel. This Panel has some behaviour which I only use on this Form.
If you want to create a special kind of Panel, one that is to be reused on several Forms, use derivation. Whether you derive from Panel or UserControl depends on how fool proof you want your class to be, and how many Panel methods users of your class may call.
If your special Panel is only to be used on one Form, don't bother to create a special Panel class. Create a Form that contains the Panel.
Use standard Panel on special Form
If you decided that you don't have to reuse the behaviour of this Panel, you can just put it on a new Form. Use visual studio designer to Create the form and put a Panel on it. Subscribe to the Panel events that you want to react on.
If you want that the form also has a Button, also use visual studio designer to add the Button and subscribe to event Button_Clicked.
To show the PanelForm, you have to decide whether the PanelForm is model or modeless.
Modal: the operator can only use this Form until it is closed. He can't use other forms of this application. This is by far the most used kind of Form: on menu selection, or button click: show the PanelForm, use the PanelForm, close the PanelForm, after which the parent form can read the results of the PanelForm and act accordingly. Modal Dialog boxes are shown using Form.ShowDialog.
Modeless: while the PanelForm is shown, the operator can switch back to the parent form and interact with it. This is not used very often. You can use it to show some extra information about the status of the parent window or application, for instance the position of the mouse, or the selected Shape that you will draw. A modeless Dialog box is shown using Form.Show(). Keep in mind, that before you close the parent form, you will have to close the modeless dialog box
Show Modal
A good example is the OpenFileDialog form
In your parent form:
using (var form = new OpenFileDialog())
{
// set properties of the OpenFileDialog before showing
form.InitialDirectory = this.GetInitialDirectory();
form.DefaultExt = ".txt";
...
// Show the Form as a modal box and wait until it is Closed
DialogResult dialogResult = form.ShowDialog(this);
// the operator has closed the form. Interpret the result:
if (dialogResult == DialogResult.OK)
{
string fileName = form.FileName();
this.OpenFile(fileName);
}
}
Modeless: operator can switch back to this form
private MyPanel PanelForm {get; set;} = null;
private void ShowMyPanel()
{
if (this.PanelForm != null) return; // panel already shown
this.PanelForm = new MyPanel();
// set properties:
this.PanelForm.DisplayedItems = ...
// show the PanelForm
this.PanelForm.Show();
}
The operator can switch back to this form, and probably close this form. In that case you will have to Close the PanelForm:
private void CloseMyPanel()
{
if (this.MyPanel != null)
{
this.MyPanel.Close();
this.MyPanel.Dispose();
this.MyPanel = null;
}
}
private void OnFormClosing(object sender, ...)
{
// if MyPanel is shown, is it allowed to Close this form AND myPanel
// or should you warn the operator to close MyPanel first?
if (this.MyPanel != null)
{
this.CloseMyPanel(); // close immediately
// or:
MessageBox.Show(..., "Please close Panelbox first");
}
}
Of course you should also react if the operator closes the panelbox. Before showing the panel box:
this.MyPane.Closed += OnMyPanelClosed;
private void OnMyPanelClosed(object sender, ...)
{
if (object.ReferenceEquals(sender, this.MyPanel)
{
// my panel is closed
this.MyPanel = null;
You can't dispose the Panel, because it is still being used. The Panel show Dispose itself when Closed.
Special Panel Class
If you have a Special Panel Class (derived from either Panel, or UserControl), then after compiling, the panel control is visible in the toolbox of visual studio designer.
You should use use visual studio designer to create a Form and put the panel on the Form:
class MyPanelForm : Form
{
public MyPanelForm()
{
InitializeComponent();
If you have used visual studio designer to add the special Panel, then you will find it in InitializeComponent. You can also add it yourself in the constructor. In that case, don't forget to add it to this.components, so your panel will be disposed when MyPanelForm is disposed.
To show MyPanelForm, use either ShowDialog or Show, as described in the previous section.
I have a form with a splitcontainer. One of the panels in the splitcontainer then loads a user control. This user control contains a combobox with the following properties changed from default:
DrowdownStyle=DrowDownList
FlatSyle=flat
Anchor=top,left,right
When the form and user control load, the combobox looks as expected:
However, if I resize the splitcontrol, it starts looking weird. If I increase the size of the panel that holds the control, this happens:
If i decrease the size of the splitter, it looks less weird, but still not how it is supposed to:
In either case, the combobox starts looking normal once I mouse over it.
Here is my code:
Main Form:
//Main form. Has a split container created from the toolbox
public partial class SampleForm:Form
{
public SampleForm()
{
InitializeComponent();
SampleControl cntrl = new SampleControl();
splitContainer1.Panel1.Controls.Add(cntrl);
splitContainer1.BorderStyle = BorderStyle.FixedSingle;
cntrl.Dock = DockStyle.Fill;
}
}
User Control:
//User control. Has a combobox created from toolbox. Options as described above
public partial class SampleControl : UserControl
{
public SampleControl()
{
InitializeComponent();
}
}
How can I fix this problem?
May be try to set dock to None . Also try to fix the margin for control
I know this is old, but was having the same problem and just in case someone finds themselves in the same predicament, answer below. Basically, create a new Class:
Imports System.Windows.Forms
Public Class MyComboBox
Inherits ComboBox
Protected Overrides Sub OnResize(e As EventArgs)
Me.Refresh()
End Sub
End Class
You can either drag this from your toolbox or add it in code. It will then auto redraw itself on resize of any parent controls.
Winforms is a bit like a sibling - flawed and deeply annoying sometimes - but you just gotta love it.
hi all and sorry for the confusing title... can't find the right words yet.
just out of curiosity, I am playing with c# user control, I created a control that is built from a panel, a textbox that is being used as a filter, and some labels / buttons/ etc... that are being filtered.
when ever you change the text of the textbox, all the controls on the panel are visible / invisible depending if their Text property contains the Text of the textbox. very simple.
but I want this user control to be such that the user that uses it can drop more labels or controls to it and they will behave the same, I can't figure out how to do that..
when I am editing the control (adding controls to it), it works as expected and the new controls behave as the old ones without code modifications, but only when I am editing the user control and not when using it.
when I am dragging the user control to a form, I can not add controls to it... when I try to add a label to the control - it is just added to the form and not to the control and therefore the text box is not influencing the added label. what should I do if I want to be able to add the control to a form and then add some controls to the control?
I will be happy for some pointers.
here is the relevant code:
private void textBox1_TextChanged(object sender, EventArgs e)
{
foreach (Control c in panel1.Controls)
{
if (c.Text.Contains(textBox1.Text))
{
c.Visible = true;
}
else
{
c.Visible = false;
}
}
}
edit - pictures added.
as you can see - i typed 1 in the filter text box and all the controls except button1 are now invisible - and of course the bad behaving label.
Thanks,
Jim.
This problem can be solved easily by following the guidelines in
https://support.microsoft.com/en-us/kb/813450 which decribes step by step How to make a UserControl object acts as a control container design-time by using Visual C#
In order to modify the user control as a design time control container
add the following code to the Declarations section:
using System.ComponentModel.Design;
Apply the System.ComponentModel.DesignerAttribute attribute to the control as follows:
[Designer("System.Windows.Forms.Design.ParentControlDesigner, System.Design", typeof(IDesigner))]
public class UserControl1 : System.Windows.Forms.UserControl
{
...
}
Then build the solution.
the control will appear as usual in the Toolbox and can be added to forms. Additional controls such as buttone , text boxes etc.. can be added to the control as required.
You describe one of the reasons why I almost never use UserControls. Anything that isn't done to the original UC must be done in code..
You can instead make it a class that is not a UserControl, ie make it a simple subclass of Panel (or FlowLayoutPanel as I do here merely for convenience, while dropping stuff on it during my tests).
class FilterPanel : FlowLayoutPanel
{
TextBox tb_filterBox { get; set; }
Label st_filterLabel { get; set; }
public FilterPanel()
{
st_filterLabel = new Label();
st_filterLabel.Text = "Filter:";
this.Controls.Add(st_filterLabel);
tb_filterBox = new TextBox();
this.Controls.Add(tb_filterBox);
// st_filterLabel.Location = new Point(10, 10); // not needed for a FLP
// tb_filterBox.Location = new Point(100, 10); // use it for a Panel!
tb_filterBox.TextChanged += tb_filterBox_TextChanged;
}
void tb_filterBox_TextChanged(object sender, EventArgs e)
{
foreach(Control ctl in this.Controls)
{
if (ctl != tb_filterBox && ctl != st_filterLabel)
ctl.Visible = ctl.Text.Contains(tb_filterBox.Text);
}
}
}
Now after placing it on a form (or whatever) you (or whoever) can drop Controls onto it in the designer and they'll be part of its Controls collection, just like you want it and will behave as expected..
Two notes on subclassing Controls:
If you break one during developement, the Form(s) using it will be broken, too, until you fix the problem. So take a little extra care!
For the Designer to display the Control it always needs to have one parameterless constructor, like the one above. Even if you prefer to have the ability to hand in parameters, one parameterless constructor must still be there or the designer will get into trouble!
In my C# application there is a main form with a panel main_panel. Whenever the user selects something in the menu, lets say "A", the main panel switches to the form A's panel (look at the code), A_panel.
Since A_panel covers every controls in form A, I can summon all of the controls of form A into main form.
if ((string)MainMenu.SelectedItem == "A")
{
FormA A = new FormA();
new_panel = A.Controls["A_panel"] as Panel;
}
this.main_panel.Controls.Clear();
this.main_panel.Controls.Add(new_panel);
My question is when user selects menu A again, I don't want to recreate FormA again by new FormA(). I did because when I add control to the main_panel, then the A_panel's ownership changes to main form so that it was possible to add the control to main_panel again.
So, how to change the ownership of A_panel to Form A again?
And how to solve my problem generally?
Any reason you can't use a UserControl and keep a reference to it on your form? That way you can just show/hide it when the user wants to change views. It would be much easier to extend and interact with. Here's a walk-through on MSDN to get you started.
It sounds like a UserControl would suit your needs better. Have one instance on FormA and another on your MainForm.
If, for some reason, you can't use user controls, you could at least extract the code outside the autogenerated designer file (which I assume is why you're using FormA at all).
As in:
FormA
public FormA()
{
var mainPanel = CreateMainPanel();
this.Controls.Add(mainPanel)
}
public Panel CreateMainPanel()
{
//...build up your control tree. Cut the code from the designer if necesssary
}
MainForm
FormA _A = new FormA();
public void HandleMainMenuClick(object sender, EventArgs e)
{
if ((string)MainMenu.SelectedItem == "A")
{
new_panel = _A.CreateMainPanel();
}
this.main_panel.Controls.Clear();
this.main_panel.Controls.Add(new_panel);
}
I'm building a small tabbed c# Form and I'd like each tab page to have some common features, notably, an OK button and an error message and to have a space for the specific form fields.
Has anyone else done something similar and how did you approach it?
This is easy to do without extending either TabControl/TabPage.
Define one UserControl, and put the common elements on it you want on every TabPage.
On the Form: go ahead and design the TabPage specific controls you want for each TabPage : make sure they are not going to visually overlap with the common controls once the UserControl has been added.
In the Form Load Event of your main Form do something like this :
// form scoped variable to hold a referece to the current UserControl
private UserControl1 currentUserControl;
private void Form1_Load(object sender, EventArgs e)
{
foreach(TabPage theTabPage in tabControl1.TabPages)
{
currentUserControl = new UserControl1();
theTabPage.Margin = new Padding(0);
theTabPage.Padding = new Padding(0);
theTabPage.Controls.Add(currentUserControl);
currentUserControl.Location = new Point(0,0);
currentUserControl.Dock = DockStyle.Fill;
currentUserControl.SendToBack();
}
}
Even though the 'SendToBack isn't really required here it is "insurance" that your UserControl with the 'Okay button and TextBox for an error message are placed behind the individual controls you have assigned to each TabPage.
Several ideas:
Keep the common controls outside the tabpanel;
Extend the TabPage/TabControl
Create a base UserControl with the common buttons and make usercontrols that inherit from it. Then place one inherited usercontrol per TabPage.