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Method with generic and multiple parameters

I want to enable/disable controls in a Windows Forms application according to the user privileges.
Initially I thought of writing a method in each form class that would check the user credentials and then enable/disable its controls. But then I realized I could (maybe) create a static class method which would take the form as a parameter and do the job.
So I started writing it, presuming that sometimes I would like to enable the controls of just one or two panels, instead of the whole form. So, I need the parameters to be:
a varying number of panels and/or
a form class.
My difficulties with this task is that I'm getting an error trying to make the panels argument varying, and I have no idea how to set a parameter that could take any form class. All my form classes obviously inherits from Form generic class, but I don't know how to apply this.
Here's what I got:
public static void Enable(TableLayoutPanel[] containers = null)
{
if (MyOF.isEnabled)
{
return;
}
else
{
try
{
foreach (TableLayoutPanel table in containers)
{
foreach (Control control in table.Controls)
{
control.Enabled = false;
}
}
}
catch (NullReferenceException)
{
}
}
}

If we remember that the Form class derives from Control (indirectly, by deriving from ContainerControl which derives from ScrollableControl, which derives from Control), and the Enabled property belongs to the Control class, we can write a method that will enable any control's children (including the Form or TableLayoutPanel controls), since the Controls collection also belongs to the Control class:
public static void EnableChildren(Control control, bool enabled = true)
{
foreach (Control child in control.Controls)
{
child.Enabled = enabled;
}
}
And then if we also want to be able to use this with a collection of controls (as in your example), we can write an overload that takes a collection:
public static void EnableChildren(IEnumerable<Control> controls = null,
bool enabled = true)
{
if (controls == null) return;
foreach (var control in controls)
{
EnableChildren(control, enabled);
}
}
Now we can use this with a Form or a collection of TableLayoutPanel controls (or any control that has controls in it's Controls collection).
Examples of usage:
var myForm = new Form1();
EnableChildren(this); // 'this' is the current form
EnableChildren(myForm); // a separate instance of a form control
EnableChildren(tableLayoutPanel1, false); // A single TableLayoutPanel control
var tableLayoutPanels = new [] {tableLayoutPanel1, tableLayoutPanel2, tableLayoutPanel3};
EnableChildren(tableLayoutPanels); // An array of tableLayoutPanel controls

One of the simple ways I can think about what you are trying to do, is this. Let me get away for a sec here. I worked on projects where all form controls were built from Metadata. And meta came with licensing info. So, when control was placed where it should, it also was disabled or set read-only based on Metadata but the whole feature would be hidden if licensing info was restricting access to it. Coming back to your approach, this is not a bad approach and I see that this is can be done. And it can be done in 2 ways, (quickly from my head).
Use user controls as surface for the components you want to enable/disable. Create an interface
public interface IDisableableControl // make your fine name, no methods needed - marker interface
. . . . .
public class MyFineUserControl : UserControl, IDisableableControl
And in your static method that you're going to write pass the form, and find all controls that implement this interface and work them the way you want.
2.
Similarly, you can use property Tag, which is available on each control. With that, you can actually set your complex security object that can come from DB-stored metadata and then you evaluate this object stored in Tag to apply your configuration
Your method needs to be recursive
internal static void SetAllControls(Control parent)
{
// Do something with control, for example parent.Enabled = false
if (parent is IDisableableControl)
{
// here you use your logic, evaluate your parent you're dialing with and
// enable/disable correspondingly
parent.Enabled = false;
return;
}
foreach(var c in parent.Controls)
SetAllControls(c);
}
In real life, your TOP parent will be a form and will not need to be disabled, but it's certain children will. In fact, most of the time, once you found a UserControl which implements IDisableableControl that should be end of line, means, you don't need to go into children controls as they all sit on this parent and all will be disabled

I manage to accomplish what I was trying to do with the code below, which is pretty much a blend of all the helpful answers I got:
public static void EnableContainer(params Control[] containers)
{
if(containers.Count() == 0) { return; }
if (MyOF.isEnabled)
{
return;
}
else
{
try
{
foreach (var container in containers)
{
foreach (Control control in container.Controls)
{
control.Enabled = false;
}
}
}
catch (NullReferenceException)
{
}
}
}
public static void EnableForm<form>(form f) where form : Form
{
if (MyOF.isEnabled)
{
return;
}
else
{
foreach(Control control in f.Controls)
{
control.Enabled = false;
}
}
}
The community is welcome to suggest improvements as I am far from being a professional programmer. Thanks everyone once again.

How to modify control properties through variable reference

I've been working on making a project of mine more modular. Something I've wanted to do is have multiple buttons use the same function when they perform a similar action, but with different values. I've been stuck on trying to apply this to the following situation:
"When this button is clicked, have the user select an image, and then have a PictureBox display the selected image". Each button has its own PictureBox. All Controls have been created before runtime.
Hope that makes sense!
My last attempt can be seen in the code below- I have tried assigning the Controls(Button and PictureBox) to variables to be stored together in a class. There's 6 of these classes all included within a single List.
I've also tried to store only the Control Names and then using this.Controls.Find to retrieve the Controls.
I've tried quite a few smaller changes such as passing by reference, making the List static, and things such as that would (somehow)magically do the trick- I've gotten desperate.
public class score_control
{
public Button score_button;
public PictureBox score_picture;
public int picture_index;
}
public List<string> score_boxes_names = new List<string>();
public List<score_control> score_boxes = new List<score_control>();
public void add_score_control(Button button, PictureBox pictureBox)
{
score_control new_score = new score_control();
new_score.score_button = button;
new_score.score_picture = pictureBox;
new_score.picture_index = score_boxes.Count();
score_boxes.Add(new_score);
score_boxes_names.Add(button.Name);
}
public score_control find_score_control(string name)
{
int index = score_boxes_names.IndexOf(name);
return score_boxes[index];
}
public frm_settings()
{
InitializeComponent();
add_score_control(btn_score1_image1, pic_score1_image1);
add_score_control(btn_score1_image2, pic_score1_image2);
add_score_control(btn_score1_image3, pic_score1_image3);
add_score_control(btn_score2_image1, pic_score2_image1);
add_score_control(btn_score2_image2, pic_score2_image2);
add_score_control(btn_score2_image3, pic_score2_image3);
}
private void score_button_Click(object sender, EventArgs e)
{
Button image_button = (Button)sender;
if (ofd_png.ShowDialog() == DialogResult.OK)
{
score_control clicked_control = find_score_control(image_button.Name);
score_image[clicked_control.picture_index] = ofd_png.FileName;
clicked_control.score_picture.Image = Image.FromFile(ofd_png.FileName);
}
}
The problem seems centered around this line:
clicked_control.score_picture.Image = Image.FromFile(ofd_png.FileName);
The program throws a NullReferenceException , but clickedcontrol is being recognized in the Local Watch, as well as score_image being noted to be a PictureBox(as it should be).
When I instead held the Control Names in the class, I had broke this line down into multiple lines, but the following line produced a NullReferenceException:
Control[] find_control = this.Controls.Find(clicked_control.score_picture, true);
In this case, clicked_control.score_picture would be a string containing the PictureBox Name. Again, the Local Watch showed that it clicked_control was not null, and neither was score_picture.
Any help figuring out how to properly store a Control within a variable to later be used to modify that Control's properties would be greatly appreciated.

dontpanic was able to help me out with this one. The issue was actually outside of this code - it had to do with the line score_image[clicked_control.picture_index] = ofd_png.FileName;. The way score_image was initialized as an array was incorrect. Fixing that made everything work fine.

Responsive Design UI with DockPanel Suite

I have design 1 winform to look like the picture. But I want the highlighted yellow part to be dockable with dockpanel suite reference. Is that do-able or any other suggestion of better design?
Right now the treeview is on the dockpanel and the red box part is a usercontrol placed in the same dockpanel. I tried to put the redbox as another form but I can't place it as it is in the picture. Also, this winform is need to be responsive so I put in the redbox part in a table layout panel.winform design and not familiar actually with the dockpanel suite reference. If there is a beginner tutorial that I can refer to, it would be much appreciated.
Current design:

There are two approach to your problem. First is dirty one and second elegant one. By dirty and elegant i mean way they display. Method they work are both same.
I will explain to you how to do it on empty form and you just implement that in your populated one.
First create new form.
Add 2 or more GroupBoxes to it
Add some items inside them (just to see if it works)
At the top of the each boxes add Button which will toggle visibility
Our form now looks like this and let's look of code behind it.
using System;
using System.Drawing;
using System.Windows.Forms;
namespace Test
{
public partial class TestForm : Form
{
// This is property
bool ShowFirstGroupBox
{
get
{
// We let user get our property from private variable
return _ShowFirstGroupBox;
}
set
{
// When user change this property we do something based on that
switch(value)
{
case true:
groupBox1.Size = new Size(groupBox1.Width, FirstGroupBoxDefaultHeight);
break;
case false:
groupBox1.Size = new Size(groupBox1.Width, 55);
break;
}
_ShowFirstGroupBox = value;
}
}
bool ShowSecondGroupBox
{
get
{
return _ShowSecondGroupBox;
}
set
{
switch (value)
{
case true:
groupBox2.Size = new Size(groupBox1.Width, FirstGroupBoxDefaultHeight);
break;
case false:
groupBox2.Size = new Size(groupBox1.Width, 55);
break;
}
_ShowSecondGroupBox = value;
}
}
// We store our boxes current state ( TRUE = shown, FALSE = HIDDEN )
bool _ShowFirstGroupBox = true;
bool _ShowSecondGroupBox = true;
// We store our default height for groupboxes
int FirstGroupBoxDefaultHeight;
int SecondGroupBoxDefaultHeight;
public TestForm()
{
InitializeComponent();
// Assigning default height of our groupboxes
FirstGroupBoxDefaultHeight = groupBox1.Height;
SecondGroupBoxDefaultHeight = groupBox2.Height;
}
private void button1_Click_1(object sender, EventArgs e)
{
ShowFirstGroupBox = !(_ShowFirstGroupBox); // This sets our property value to opposite of this boolean
}
private void button1_Click_1(object sender, EventArgs e)
{
ShowSecondGroupBox = !(_ShowSecondGroupBox); // This sets our property value to opposite of this boolean
}
}
}
Now when we have code like this and press button it will collapse groupbox.
NOTE: Controls under groupbox are still on place but just hidden since they are child of groupbox and everything outside of bounds is not visible to user.
This is dirty way since i would like to display it much prettier with MINUS sign on the right side of the groupbox title so i do not have button inside it. To do this you would need to create custom control which inherits groupbox, add button to it and position it in title bar and create event for it. It is easy if you have ever tried creating custom controls but if you haven't and you think dirty approach is okay with you then do not try it.

Draw adornments on windows.forms.controls in Visual Studio Designer from an extension

I wrote an Visual Studio 2013 extension that observes Windows.Forms designer windows. When a developer is changing controls in the designer window, the extension tries to verify that the result is consistent with our ui style guidelines. If possible violations are found they are listed in a tool window. This all works fine.
But now I would like to mark the inconsistent controls in the designer window, for example with a red frame or something like this.
Unfortunately, I did not find a way to draw adornments on controls in a designer window. I know that you can draw those adornments if you develop your own ControlDesigner, but I need to do it from "outside" the control's designer. I only have the IDesignerHost from the Dte2.ActiveWindow and can access the Controls and ControlDesigners via that host. I could not find any way to add adornments from "outside" the ControlDesigners.
My workaround for now is to catch the Paint-Events of the controls and try to draw my adornments from there. This doesn't work well for all controls (i.e. ComboBoxes etc), because not all controls let you draw on them. So I had to use their parent control's Paint event. And there are other drawbacks to this solution.
I hope someone can tell me if there is a better way. I'm pretty sure that there has to be one: If you use Menu->View->Tab Order (not sure about the correct english menu title, I'm using a german IDE), you can see that the IDE itself is able to adorn controls (no screenshot because it's my first post on SO), and I'm sure it is not using a work around like me. How does it do that?
I've been googling that for weeks now. Thanks for any help, advice, research starting points....
UPDATE:
Maybe it gets a little bit clearer with this screenshot:
Those blue numbered carets is what Visual Studio shows when selecting Tab order from the View menu. And my question is how this is done by the IDE.
As mentioned I tried to do it in the Paint event of the controls, but e.g. ComboBox doesn't actually support that event. And if I use the parent's Paint event I can only draw "around" the child controls because they are painted after the parent.
I also thought about using reflection on the controls or the ControlDesigners, but am not sure how to hook on the protected OnPaintAdornments method. And I don't think the IDE developers used those "dirty" tricks.

I believe you are seeking for BehaviorService architecture. The architecture with supporting parts like Behavior, Adorner and Glyph and some examples is explained here Behavior Service Overview. For instance
Extending the Design-Time User Interface
The BehaviorService model enables new functionality to be easily layered on an existing designer user interface. New UI remains independent of other previously defined Glyph and Behavior objects. For example, the smart tags on some controls are accessed by a Glyph in the upper-right-hand corner of the control (Smart Tag Glyph).
The smart tag code creates its own Adorner layer and adds Glyph objects to this layer. This keeps the smart tag Glyph objects separate from the selection Glyph objects. The necessary code for adding a new Adorner to the Adorners collection is straightforward.
etc.
Hope that helps.

I finally had the time to implement my solution and want to show it for completeness.
Of course I reduced the code to show only the relevant parts.
1. Obtaining the BehaviorService
This is one of the reasons why I don't like the service locator (anti) pattern. Though reading a lot of articles, I didn't came to my mind that I can obtain a BehaviorService from my IDesignerHost.
I now have something like this data class:
public class DesignerIssuesModel
{
private readonly BehaviorService m_BehaviorService;
private readonly Adorner m_Adorner = new Adorner();
private readonly Dictionary<Control, MyGlyph> m_Glyphs = new Dictionary<Control, MyGlyph>();
public IDesignerHost DesignerHost { get; private set; }
public DesignerIssuesModel(IDesignerHost designerHost)
{
DesignerHost = designerHost;
m_BehaviorService = (BehaviorService)DesignerHost.RootComponent.Site.GetService(typeof(BehaviorService));
m_BehaviorService.Adornders.Add(m_Adorner);
}
public void AddIssue(Control control)
{
if (!m_Glyphs.ContainsKey(control))
{
MyGlyph g = new MyGlyph(m_BehaviorService, control);
m_Glyphs[control] = g;
m_Adorner.Glyphs.Add(g);
}
m_Glyphs[control].Issues += 1;
}
public void RemoveIssue(Control control)
{
if (!m_Glyphs.ContainsKey(control)) return;
MyGlyph g = m_Glyphs[control];
g.Issues -= 1;
if (g.Issues > 0) return;
m_Glyphs.Remove(control);
m_Adorner.Glyphs.Remove(g);
}
}
So I obtain the BehaviorService from the RootComponent of the IDesignerHost and add a new System.Windows.Forms.Design.Behavior.Adorner to it. Then I can use my AddIssue and RemoveIssue methods to add and modify my glyphs to the Adorner.
2. My Glyph implementation
Here is the implementation of MyGlyph, a class inherited from System.Windows.Forms.Design.Behavior.Glyph:
public class MyGlyph : Glyph
{
private readonly BehaviorService m_BehaviorService;
private readonly Control m_Control;
public int Issues { get; set; }
public Control Control { get { return m_Control; } }
public VolkerIssueGlyph(BehaviorService behaviorService, Control control) : base(new MyBehavior())
{
m_Control = control;
m_BehaviorService = behaviorService;
}
public override Rectangle Bounds
{
get
{
Point p = m_BehaviorService.ControlToAdornerWindow(m_Control);
Graphics g = Graphics.FromHwnd(m_Control.Handle);
SizeF size = g.MeasureString(Issues.ToString(), m_Font);
return new Rectangle(p.X + 1, p.Y + m_Control.Height - (int)size.Height - 2, (int)size.Width + 1, (int)size.Height + 1);
}
}
public override Cursor GetHitTest(Point p)
{
return m_Control.Visible && Bounds.Contains(p) ? Cursors.Cross : null;
}
public override void Paint(PaintEventArgs pe)
{
if (!m_Control.Visible) return;
Point topLeft = m_BehaviorService.ControlToAdornerWindow(m_Control);
using (Pen pen = new Pen(Color.Red, 2))
pe.Graphics.DrawRectangle(pen, topLeft.X, topLeft.Y, m_Control.Width, m_Control.Height);
Rectangle bounds = Bounds;
pe.Graphics.FillRectangle(Brushes.Red, bounds);
pe.Graphics.DrawString(Issues.ToString(), m_Font, Brushes.Black, bounds);
}
}
The details of the overrides can be studied in the links posted in the accepted answer.
I draw a red border around (but inside) the control and add a little rectangle containing the number of found issues.
One thing to note is that I check if Control.Visible is true. So I can avoid to draw the adornment when the control is - for example - on a TabPage that is currently not selected.
3. My Behavior implementation
Since the constructor of the Glyph base class needs an instance of a class inherited from Behavior, I needed to create a new class. This can be left empty, but I used it to show a tooltip when the mouse enters the rectangle showing the number of issues:
public class MyBehavior : Behavior
{
private static readonly ToolTip ToolTip = new ToolTip
{
ToolTipTitle = "UI guide line issues found",
ToolTipIcon = ToolTipIcon.Warning
};
public override bool OnMouseEnter(Glyph g)
{
MyGlyph glyph = (MyGlyph)g;
if (!glyph.Control.Visible) return false;
lock(ToolTip)
ToolTip.Show(GetText(glyph), glyph.Control, glyph.Control.PointToClient(Control.MousePosition), 2000);
return true;
}
public override bool OnMouseLeave(Glyph g)
{
lock (ToolTip)
ToolTip.Hide(((MyGlyph)g).Control);
return true;
}
private static string GetText(MyGlyph glyph)
{
return string.Format("{0} has {1} conflicts!", glyph.Control.Name, glyph.Issues);
}
}
The overrides are called when the mouse enters/leaves the Bounds returned by the MyGlyph implementation.
4. Results
Finally I show screenshot of a example result. Since this was done by the real implementation, the tooltip is a little more advanced. The button is misaligned to all the comboboxes, because it's a little too left:
Thanks again to Ivan Stoev for pointing me to the right solution. I hope I could make clear how I implemented it.

Use the System.Drawing.Graphics.FromHwnd method, passing in the HWND for the designer window.
Get the HWND by drilling down into the window handles for visual studio, via pinvoke. Perhaps use tools like Inspect to find window classes and other information that might help you identify the correct (designer) window.
I've written a C# program to get you started here.

Can I give controls an index property in C# like in VB?

I've found similar answers to my question before, but not quite to what I'm trying to do...
In Visual Basic (last I used it, in 06/07) there was an "Index" property you could assign to multiple controls with the same name. I used this primarily to loop through controls, i.e.:
For i = 1 to 500
picSeat(i).Print "Hello"
Next i
Is there a way to do this in C#? I know there is a .IndexOf(), but would that really help for what I'm doing? I want to have multiple controls with the same name, just different index.
This is a Windows Form Application, and I'm using Visual Studio 2012. I am talking about controls, not arrays/lists; this was possible in VB and I was wondering if it was possible at all in C#. So I want to have, say, 30 seats in a theatre. I want to have each seat represented by a picturebox named "picSeat". VB would let me name several objects the exact same, and would assign a value to a control property "Index". That way, I could use the above loop to print "Hello" in every picture box with only 3 lines of code.

No, this feature does not exist in C#, and was never implemented in the transition from classic VB to VB.Net.
What I normally do instead is put each of the controls in question in a common parent container. The Form itself can work, but if you need to distinguish these from others of the same type a GroupBox or Panel control will work, too. Then, you access the controls like this:
foreach (var picBox in parentControl.Controls.OfType<PictureBox>())
{
// do something with each picturebox
}
If you want to use a specific control, just write by name:
pictureBox6.SomeProperty = someValue;
If you need to change a specific control determined at run-time, normally this is in response to a user event:
void PictureBox_Click(object sender, EventArgs e)
{
var picBox = sender As PictureBox;
if (picBox == null) return;
//picBox is now whichever box was clicked
// (assuming you set all your pictureboxes to use this handler)
}
If you really really want the Control Arrays feature, you can do it by adding code to create the array to your form's Load event:
PictureBox[] pictureBoxes = Me.Controls.OfType<PictureBox>().ToArray();

Are we talking WinForms here? I'm not sure, but I don't think you can have multiple controls in winforms with same name. But I vaguely recall doing something similar and the solution was to name them Button_1, Button_2 etc. Then you can iterate through all controls and get your own index.
Beware though that if you want to instanciate a separate control for each seat in a theatre, you might run into some serious performance issues :) I've done something similar to that as well and ended up drawing the whole thing on a canvas and using mouse coordinates to handle the events correctly.

You may want to check out the Uid property of controls.
(http://msdn.microsoft.com/en-us/library/system.windows.uielement.uid(v=vs.110).aspx)
You can access Control through Uid property with the following
private static UIElement FindUid(this DependencyObject parent, string uid)
{
var count = VisualTreeHelper.GetChildrenCount(parent);
if (count == 0) return null;
for (int i = 0; i < count; i++)
{
var el = VisualTreeHelper.GetChild(parent, i) as UIElement;
if (el == null) continue;
if (el.Uid == uid) return el;
el = el.FindUid(uid);
if (el != null) return el;
}
return null;
}
And simply use
var control = FindUid("someUid");
I copied code from this post

If you create an indexed dictionary of your user control, it will behave pretty much the same as in VB6, though you'll not see it on the VS C# GUI. You'll have to get around the placement issues manually. Still - and most importantly -, you'll be able to refer to any instance by the index.
The following example is for 3 pieces for clarity, but of course you could automate every step of the process with appropriate loops.
public partial class Form1 : Form
{
...
Dictionary<int, UserControl1> NameOfUserControlInstance = new Dictionary<int, UserControl1>()
{
{ 1, new UserControl1 {}},
{ 2, new UserControl1 {}},
{ 3, new UserControl1 {}}
};
private void Form1_Load(object sender, EventArgs e)
{
NameOfUserControlInstance[1].Location = new System.Drawing.Point(0, 0);
NameOfUserControlInstance[2].Location = new System.Drawing.Point(200, 0);
NameOfUserControlInstance[3].Location = new System.Drawing.Point(400, 0);
Controls.Add(NameOfUserControlInstance[1]);
Controls.Add(NameOfUserControlInstance[2]);
Controls.Add(NameOfUserControlInstance[3]);
}
...
}

I like using Tags to apply any type of meta data about the controls
for (int i = 0; i< 10; ++i)
{
Button button = new Button();
button.Tag = i;
}