Is it possible to set a components visible attribute based on its name?
I have 12 "master" components (comboboxes) if you want to call them that and based on the selection in these I want to display anywhere from 1 to 16 textboxes. These are named in numeric order such as combobox1_textbox_0, combobox1_textbox_1 and so on. What I would like to do ideally is take the index of the combobox and pass it as a parameter to a method that sets the textboxes visible attribute to visible/hidden depending on the index passed into the method.
Is this possible? in pseudocode or what you call it I would like it to work something like this:
private void methodToSetVisibleAttribute(int indexFromMainComboBox)
{
for(int i = 0; i < 15; i++)
{
if(i < index)
{
combobox1_textbox_+i.Visible = true;
}
else
{
combobox1_textbox_+i.Visible = false;
}
}
}
I could do panels or something for the choices but seeing as all the selections from the combobox will use the same textboxes but in different amounts it seems like alot of work to make a panel for every possible selection not to mention difficult to expand the program later on.
Assuming you are using Windows Forms and not WPF, you can use ControlCollection.Find() to find controls by name:
var textBox = this.Controls.Find(string.Format("combobox1_textbox_{0}", i), true).OfType<ComboBox>().FirstOrDefault();
if (textBox != null)
textBox.Visible = (i < index);
else
Debug.Assert(false, "textbox not found"); // Or throw an exception if you prefer.
I'll suggest an alternative to your approach, maybe not quite what you're looking for:
Place your combo boxes in a List<ComboBox> and you can access them by an index number.
List<ComboBox> myCombos = new List<ComboBox>();
for (int i = 0; i < 16; i++)
{
ComboBox cb = new ComboBox();
//do what ever you need to do here. Set its location, add items, etc.
Form1.Controls.Add(cb); //Alternatively add it to another container.
myCombos.Add(cb); //Now it's in a list.
}
Modify them like this:
for(int i = 0; i < 15; i++)
{
if(i < index)
{
myCombos[i].Visible = true;
}
else
{
myCombos[i].Visible = false;
}
}
Or even more succintly:
for(int i = 0; i < 15; i++)
{
myCombos[i].Visible = i < index;
}
Related
I want to create labels that will follow one another. I have a grid name WordTemplateLayout to which I want to add the labels. I add them dynamically on the wpf window constructor after InitializeComponent() is called. Here is the method creating the labels:
private void CreateWordTemplate()
{
IList<char> template = CurrentGame.Template;
double widthPerBox = WordTemplateLayout.Width / template.Count;
//template.Count being a number, irrelevant to the question
for (int i = 0; i < template.Count; i++)
{
var templateVisual = new Label();
templateVisual.Name = "c" + i;
templateVisual.Width = widthPerBox;
templateVisual.Height = WordTemplateLayout.Height;
templateVisual.Background = new SolidColorBrush(Colors.Aqua);
WordTemplateLayout.Children.Add(templateVisual);
}
}
the problem being, that what actually appends is that instead of the labels lining up one after the other, they overlap each other:
The aqua box is all the labels overlap each other
so what I am asking, is how can I make the labels line up (horizontally) instead of to overlap?
As others have pointed out, you're better off using a StackPanel, or learning how to use viewmodels and data binding. Having said that, to answer your direct question, here's how you'd do it programmatically.
**NOTE: Ignore the 5 that I'm passing in to the methods, and instead use your template.Count. This is was just for me to get it to work on my end.
public MainWindow()
{
InitializeComponent();
CreateGridLayout(5);
CreateWordTemplate(5);
}
// Define the Grid layout
// If you want the labels to follow one another horizontally, define columns.
// If you want them stacked vertically, instead define rows.
private void CreateGridLayout(int count)
{
for (int i = 0; i < count; i++)
{
WordTemplateLayout.ColumnDefinitions.Add(new ColumnDefinition());
}
}
private void CreateWordTemplate(int count)
{
double widthPerBox = WordTemplateLayout.Width / 5;
for (int i = 0; i < 5; i++)
{
var templateVisual = new Label();
templateVisual.SetValue(Grid.ColumnProperty, i); // SET YOUR COLUMN HERE!
templateVisual.Name = "c" + i;
templateVisual.Width = widthPerBox;
templateVisual.Height = WordTemplateLayout.Height;
templateVisual.Background = new SolidColorBrush(Colors.Aqua);
templateVisual.Content = templateVisual.Name;
WordTemplateLayout.Children.Add(templateVisual);
}
}
you need to use another layout so the new elements will get in normal order. try stackPanel.
you can use grid and give each new label Row=index.
you can give each new label margin, like newLabel.margin-top = index*50
So I have this and I know it is wrong:
protected override void OnSelectionChangeCommitted(EventArgs e)
{
if (SelectedIndex == 0)
{
GENIO_Viewer.FullColourPaletteForm dlgColour = new GENIO_Viewer.FullColourPaletteForm();
if(dlgColour.ShowDialog() == DialogResult.OK)
{
bool bFound = false;
for(int i = 1; i < Items.Count; i++)
{
ComboboxColourItem ocbItem = (ComboboxColourItem)Items[i];
if(ocbItem.Index == dlgColour.iSelectedColour)
{
SelectedIndex = i;
bFound = true;
break;
// We can just select this one
}
}
if(!bFound)
{
// Add it
ComboboxColourItem ocbItem = ComboboxColourItem.Create((ushort)dlgColour.iSelectedColour);
Items.Add(ocbItem);
SelectedIndex = Items.Count - 1;
}
}
}
base.OnSelectionChangeCommitted(e);
}
This handler is part of my DataGridViewComboBoxEditingControl. But it is the wrong place to add new Items.
I can't workout how to get access to the owning Column as that is where I need to add the Item, otherwise I get exceptions.
I have looked here: https://msdn.microsoft.com/en-us/library/system.windows.forms.datagridviewcomboboxeditingcontrol(v=vs.110).aspx
But i can't see a property I can use to get the column object.
How do we do this from the editing control?
Further explaination:
The list combo items are added by the "column" object. Thus we have a set of 15 colours to choose from. Now I have added a genric colour tot he top of the list.
So, the user invokes the edit, droplist displays, and they pick item 0. We intercept this with the aforementioned handler. Since they picked item 0, we show a popup dialogue to let them choose a different colour.
When they have chosen, we must now either find it or add it to the the mandatory list of items for the column. Make sense now?
I tried to use the DataGridView Notify object but for some reason it is not showing in the list of available functions.
I don't use a DataSource. I populate like this in the columns constructor:
private void InitialiseComboItems()
{
List<ushort> listColours = new List<ushort>();
listColours.Add(0);
listColours.Add(1);
listColours.Add(2);
listColours.Add(3);
listColours.Add(4);
listColours.Add(5);
listColours.Add(6);
listColours.Add(7);
listColours.Add(8);
listColours.Add(9);
listColours.Add(250);
listColours.Add(251);
listColours.Add(252);
listColours.Add(253);
listColours.Add(254);
listColours.Add(255);
this.Items.Clear();
foreach (ushort iColourIndex in listColours)
this.Items.Add(ComboboxColourItem.Create(iColourIndex));
}
I also have a helper method:
public ComboboxColourItem InsertColour(ushort iColourIndex)
{
ComboboxColourItem ocbItem = ComboboxColourItem.Create(iColourIndex);
bool bAppend = true;
if (Items.Count > 16)
{
// There are other colours, need to find right index
for(int i = 16; i < Items.Count; i++)
{
if(ocbItem.Index < ((ComboboxColourItem)Items[i]).Index)
{
bAppend = false;
Items.Insert(i, ocbItem);
break;
}
}
}
if (bAppend)
Items.Add(ocbItem);
return ocbItem;
}
You can use EditingControlDataGridView to find the DataGridView which owns the editing control. Then you can use CurrentCell property of grid to find the current cell and using ColumnIndex you will find the column index. Then using Columns collection, you can get the column at that index:
var c = this.EditingControlDataGridView
.Columns[this.EditingControlDataGridView.CurrentCell.ColumnIndex]
as DataGridViewComboBoxColumn;
if (c != null)
c.Items.Add("Something");
I have the WinForm, there I have a lot of controls, and on certain moments I need to change the properties for some of them.. so, I create the Control array and determines what should be changed
controls = new Control[] {loadFromFile_btn, logout_btn, postBtn, waitFrom_tb, waitTo_tb, messageTB, recurs_check};
ChangeStatus.activStatus(controls);
Then in my class ChangeStatus make changes to all of these elements are in an array
public static void activStatus(Control[] controlObj)
{
for (int i = 0; i < controlObj.Count() - 1; i++)
{
controlObj[i].BeginInvoke((Action)delegate
{
if (controlObj[i] is TextBox || controlObj[i] is CheckBox || controlObj[i] is Panel)
controlObj[i].Enabled = true;
else
{
controlObj[i].BackColor = Color.DarkGray;
controlObj[i].Enabled = true;
}
});
}
}
But I have a problem... the change applies only to the last element in the array. Help me please..
That's because of the closure.Try storing i in a local variable and use it in your anonymous method
for (int i = 0; i < controlObj.Count() - 1; i++)
{
int j = i;
controlObj[i].BeginInvoke((Action)delegate
{
if (controlObj[j] is TextBox || controlObj[j] is CheckBox || controlObj[j] is Panel)
controlObj[j].Enabled = true;
else
{
controlObj[j].BackColor = Color.DarkGray;
controlObj[j].Enabled = true;
}
});
}
I'm trying to make a small app, for make my job easier creating definitions (new web forms aspx) via WinForms C#.
Now I have this form, where I tell the app how many textboxes I want to create.
After their creation, I want to assign to a string the textboxes values that I wrote.
private void CreateControls()
{
for (int index = 0; index < NumberOfRows; index++)
{
TextBox textBox = new TextBox();
textBox.Name = "TextBox" + (index + 1).ToString();
textBox.Size = new Size(120, 20);
textBox.Location = new Point(X, Y + 26);
ComboBox comboBox = new ComboBox();
comboBox.Name = "ComboBox" + (index + 1).ToString();
comboBox.Size = new Size(75, 20);
comboBox.Location = new Point(141, Y + 26);
comboBox.DataSource = Enum.GetNames(typeof(DataTypes));
Y += 26;
this.Controls.Add(textBox);
this.Controls.Add(comboBox);
}
}
Now, I don't know how to check if the textboxes are created, and then take their values.
Could anyone refer me something? Thanks :)!
You'll need to, on Page_Load, find those controls and grab their values. Since you gave them meaningful names when you created them, this should do the trick:
for (int index = 0; index < NumberOfRows; index++)
{
TextBox textBox = this.FindControl(
string.Format("TextBox{0}", index)) as TextBox;
if (textBox == null) { continue; } // this means it wasn't found
var text = textBox.Text;
// work with the text
}
However, if the ComboBox class you're using isn't a third-party one and it's not an ASP.NET application, the code would work for a Windows Forms application as well with a minor modification:
for (int index = 0; index < NumberOfRows; index++)
{
// you have to use the Find method of the ControlCollection
TextBox textBox = this.Controls.Find(
string.Format("TextBox{0}", index)) as TextBox;
if (textBox == null) { continue; } // this means it wasn't found
var text = textBox.Text;
// work with the text
}
I tend to agree with the community that it's probably a Windows Forms application because you can't set the Location of a standard ASP.NET control. However, if these are user controls, or third-party ones, that support those properties and render the appropriate CSS then we'd never know.
if(Page.FindControl("IDofControl") != null)
//exists
else
//does no exists
How do you change the text of a button in Windows Phone 7 and C#? NullPointer Exception too, if I am doing the changing of the button text right, what is the problem?
public void CreateWords(Word[] theWords)
{
listOfWords = new Button[theWords.Length]; //Button Array
textBlock1.Text = theWords[0].getWord(); //Totally Works
for (int i = 0; i < theWords.Length; i++)
{
listOfWords[i].Content = theWords[0].getWord(); //NullPointer Exception
}
for (int i = 0; i < theWords.Length; i++)
{
stackWords.Children.Add(listOfWords[i]);
}
}
You're getting the NullReferenceException because, while you have created the new Button array, you haven't initialized any of the elements of that array (each element is still null).
As Justin said earlier, you have just created an Array of the Type of Button, You have not added any Button's to the Array as of yet. You need to explicitly set each index of the Array to a Button: Try doing something like this.
for (int i = 0; i < theWords.Length; i++)
{
listOfWords[i] = new Button();
listOfWords[i].Content = theWords[0].getWord(); //NullPointer Exception
}