I have a child form that displays with a button in user control and I want to clone ListView in user control to its child form.
I checked with breakpoint and printed the list but it gives me error like out of bounds or instance variable is zero.
public partial class JobForm: Form
{
public Job()
{
InitializeComponent();
}
List<string> joblist = new List<string>();
public List<string> _var
{
set {
joblist = value; }
}
}
User Control
private void button_Click(object sender, EventArgs e)
{
//MessageBox.Show(_var[0].ToString());
JobForm jb = new JobForm();
jb.Show();
}
public List<string> listViewJob()
{
_var.Add(item);
return _var;
}
public List<string> _var { get;} = new List<string>();
I used also 'var parent = this.Parent as JobForm; parent.ID2 = ID2; but it gives me same error. So I check with breakpoint it is a correct list until the form shows then I get null or out of bound (_var) in User Control and in Form. I would appreciate if you could write an example.
It is very confusing that both JobForm and the user control have a list called _var. Its best to use more descriptive variable names.
I'm not completely sure what you want to achieve, but basically, when you have created the child form you can access its properties.
For instance:
private void button_Click(object sender, EventArgs e)
{
//MessageBox.Show(_var[0].ToString());
JobForm jb = new JobForm();
// Members of 'jb' are available here
this._var = jb._var;
jb.Show();
}
Related
I'm having problems. I get a lot of errors and this is annoying me when I'm trying to add tabs from a user control.
Here is the code
public Form1 f1 { get; private set; }
private void button1_Click(object sender, EventArgs e)
{
TabPage tp = new TabPage { };
tp.Text = "NewTab";
tp.Controls.Add(new b());
f1.tabControl1.TabPages.Add(tp); //>>> errors here
}
Image for more details: code no showing errors
Run-time errors
Your code isn't assigning f1 which is why you are getting a null reference exception at run time.
Depending on the architecture of your project ...
A. If UserControl is instantiated in the parent Form code behind then simply inject f1 into the constructor of the UserControl:
private readonly MyForm _f1;
public b(MyForm f1){
InitializeComponents();
_f1 = f1;
}
private void button1_Click(object sender, EventArgs e) {
TabPage tp = new TabPage { };
tp.Text = "NewTab";
tp.Controls.Add(new b());
// assumes 'tabControl1' exists as a publicly accessible control
_f1.tabControl1.TabPages.Add(tp);
}
B. If using M-V-P then, using the code you have, the Presenter can assign the f1 variable at initialization but make the setter public or internal.
f1 is null because no form has been assigned to it. Drop this property and instead write:
TabPage tp = new TabPage { };
tp.Text = "NewTab";
tp.Controls.Add(new b());
FindForm().Controls.OfType<TabControl>().Single().TabPages.Add(tp);
This assumes that the form contains exactly one TabControl and that it is a top level control. If it can be inside another container control, you will have to loop the controls recursively. This question might help: Loop through all controls on a form, even those in groupboxes
Note, that your approach has yet another issue: f1 is typed as Form, but this general type has no tabControl1. You would have to type it with a specific form type MyForm f { get; set; }.
Maybe an easier way to access the TabControl is to let the form implement an interface defining just a property returning this TabControl:
public interface ITabControlProvider
{
TabControl MainTabControl { get; }
}
Then let your form implement it
public partial class MyForm : Form, ITabControlProvider
{
...
TabControl MainTabControl { get { return tabControl1; } }
}
Now your UserControl can find the TabControl like this
var frm = FindForm() as ITabControlProvider;
if (frm != null) {
frm.MainTabControl.TabPages.Add(tp);
}
As this code looks like it is all happening from inside a form, you can try this :
public Form1 f1 { get; private set; }
private void button1_Click(object sender, EventArgs e)
{
if(f1 == null) { f1 = this; }
TabPage tp = new TabPage { };
tp.Text = "NewTab";
tp.Controls.Add(new b());
f1.tabControl1.TabPages.Add(tp); //>>> errors here
}
If it is happening inside a UserControl, then you can try this :
public Foo : UserControl {
public TabControl tabControl { get; set; }
private void button1_Click(object sender, EventArgs e)
{
if(tabControl == null) {
// do nothing - ignore button click.
} else {
TabPage tp = new TabPage { };
tp.Text = "NewTab";
tp.Controls.Add(new b());
tabControl.TabPages.Add(tp); //>>> errors here
}
}
}
The on the form you have this user control added to, you can either choose the TabControl it is bound to from the drop-down menu in the property editor, or you can assign it in code like this :
foo1.tabControl = tabControl1;
Suppose i have created a WPF form having one text box. i am calling that form inside another wpf window's gridpanel and after entering value inside the textbox, i am clicking on submit button. After button click, i need to get that value and save it in string form inside my current class. My logic is something like this.
For getting the from inside my current window:-
void SelectedClick(object sender, RoutedPropertyChangedEventArgs<object> e)
{
selectedItem.ContextMenu = VcontextMenu;
VcontextMenu.Items.Add(VmenuItem1);
VmenuItem1.Click += AddValidation;
details();
}
void AddValidation(object sender, RoutedEventArgs e)
{
ValidationForm obj = new ValidationForm();
ProcessGrid.Content = obj.VForm;
}
Now i want to store the value of my textbox inside a string. For that i have used following code:-
public void details()
{
ValidationForm obj = new ValidationForm();
string str = obj.s.ToString();
}
My ValidationForm Code:-
public partial class ValidationForm : UserControl
{
public string s { get; set; }
public ValidationForm()
{
InitializeComponent();
}
public void XSave_Click(object sender, RoutedEventArgs e)
{
s = TextValidationName.Text;
}
}
but instead of opening the form, the control is going to obj.s.ToString() and showing error as "Object reference not set to an instance of an object." Please help. Thanks.
The issue is caused since the string s in your ValidationForm class is not assigned. It is probably caused since the XSave_Click() method is not being called.
Ensure that you properly assign the value to s before you try to get value from it.
Im running into a bit of an issue regarding Children and parents.
I have 2 forms which have the same dropdown menus, both of which have the ability to add additional options to them. When the "(add new)" option is selected in any of the combo boxes my third form is loaded which enables the addition of a new option.
This is the code for that third window (as it stands)
public partial class taskNewDropdownEntry : Form
{
taskWindow _owner;
applianceWindow _owner2;
int windowType;
int manufacturer_id;
sqlMod data = new sqlMod();
public int setManufacturerID {get { return manufacturer_id; } set { manufacturer_id = value; } }
public taskNewDropdownEntry(taskWindow owner, int type)
{
InitializeComponent();
this._owner = owner;
this.windowType = type;
}
public taskNewDropdownEntry(applianceWindow owner, int type)
{
InitializeComponent();
this._owner2 = owner;
this.windowType = type;
}
private void taskNewDropdownEntry_Load(object sender, EventArgs e)
{
if (windowType == 1)
{
instructionLabel.Text = "Input the new appliance type below";
}
else if (windowType == 2)
{
instructionLabel.Text = "Input the new manufacturer below";
}
else if (windowType == 3)
{
instructionLabel.Text = "Input the new model below";
}
}
private void btnOK_Click(object sender, EventArgs e)
{
if (windowType == 1)
{
data.insertApplianceType(textField.Text);
_owner.refreshTypeCombo();
}
else if (windowType == 2)
{
data.insertManufacturerSimple(textField.Text);
_owner.refreshManuCombo();
}
else if (windowType == 3)
{
data.insertModelSimple(manufacturer_id, textField.Text);
_owner.refreshModelCombo();
}
this.Close();
}
private void btnCancel_Click(object sender, EventArgs e)
{
this.Close();
}
}
Now, my issue is that the 2 forms that call this third form are different - thus my only thought of how to solve this would be to duplicate some of the code and modify the methods (you can see the second constructor already added).
Instead of having multiple constructors, and duplicated methods (in this class, or in a seperate one) is there a way whereby I can use the same constructor but different owners depending on the form that calls it?
You have too much implementation in your child form. The way I would tackle this is to
Add a property to your child form:
public string InstructionLabel { get; set; }
This allows your parent forms to individually set the label text when instantiating the form, and also set up an event handler for when the form is closing. So your parent form would have code something like
var newItemForm = new taskNewDropdownEntry();
newItemForm.InstructionLabel = "Input the new appliance type below";
newItemForm.FormClosing += new FormClosingEventHandler(ChildFormClosing);
Then somewhere early in your child form's life cycle (FormLoading event) set
instructionLabel.Text = InstructionLabel;
Then also add a property in the child form for
public string NewItem { get; set; }
your child form should set this public property in the btnOK_Click event
private void btnOK_Click(object sender, EventArgs e)
{
this.NewItem =textField.Text;
}
Then your parent form listens for a FormClosing event, and when it hits that event it takes the NewItem text, adds it to the relevant combo and refreshes it. So in the parent form, the handler looks like
private void ChildFormClosing(object sender, FormClosingEventArgs e)
{
sqlMod data = new sqlMod();
data.insertApplianceType(textField.Text);
refreshTypeCombo();
}
Pretty hard to understand the question but code speaks for all.
There are 2 options, worse (because keeping the parent reference is not a good practice first of all):
create an interface that both classes taskWindow and applianceWindow (where is the naming convention for god's sake!) implement, ex
intrerface IRefreshable {
void refreshManuCombo();
}
then constructor and your poperty can have type of IRefreshable
IRefreshable _owner;
public taskNewDropdownEntry(IRefreshable owner, int type)
{
InitializeComponent();
this._owner = owner;
}
better option, use child form events like Closed to implement refreshing logic in parent. You just need to register event handler before showing the form and voila. Check examples here:
https://msdn.microsoft.com/en-us/library/system.windows.forms.form.closed(v=vs.110).aspx
You can also implement your own public form event for more custom usage (ex. DataChanged, ResultGenerated).
I've got code and i know I'm 99% of the way there. C# coding in MS VS2008.
Basically I have a form that has 4 radio buttons and a Continue button. the user clicks one of the radio buttons and clicks continue, and this all works fine.
However, I want to use the value entered by the user (i.e. if they click the first button, I want a variable equal to 1, 2nd button equals 2 and so on). I tried doing this in various points but the only place I can get it to run is in the private void btnOkClick line, which means I can use the values outside this void, which is what I really want.
I've tried playing around with setting some enums and such (commented out in the code below), but I can't quite get it. I know I must be close but my novice-ness is truly showing as I keep reading posts and can't quite grasp it.
In short, I want to be able to have other classes in my VS2008 project be able to reference whatever value the user selected in the initial form.
namespace AmortClient
{
public partial class frmLoadACTFCST : Form
{
public frmLoadACTFCST()
{
InitializeComponent();
//set the parent of the form to the container
//this.MdiParent = parent;
}
//public enum ACTFCST
//{
// ACT = 1,
// FCST = 2,
// PLAN = 3,
// FiveYearPlan2012=4
//}
//private ACTFCST _actfcst = ACTFCST.ACT;
//public ACTFCST actfcst
//{
// get { return _actfcst; }
// set { _actfcst = value; }
//}
private void frmLoadACTFCST_Load(object sender, EventArgs e)
{
}
private void groupBox1_Enter(object sender, EventArgs e)
{
}
private void btnActual_CheckedChanged(object sender, EventArgs e)
{
}
private void btnForecast_CheckedChanged(object sender, EventArgs e)
{
}
private void btnPlan_CheckedChanged(object sender, EventArgs e)
{
}
private void btn5YrPlan2012_CheckedChanged(object sender, EventArgs e)
{
}
private void btnContinue_Click(object sender, EventArgs e)
{
string ACTFCSTtext = "";
int dataTypeKey = 0;
if (btnActual.Checked)
{
ACTFCSTtext = btnActual.Text;
dataTypeKey = 1;
}
else if (btnForecast.Checked)
{
ACTFCSTtext = btnForecast.Text;
dataTypeKey = 2;
}
else if (btnPlan.Checked)
{
ACTFCSTtext = btnPlan.Text;
dataTypeKey = 3;
}
else if (btn5YrPlan2012.Checked)
{
ACTFCSTtext = btn5YrPlan2012.Text;
dataTypeKey = 4;
}
string msg = "";
msg = ACTFCSTtext + " " + dataTypeKey;
//btn5YrPlan2012
MessageBox.Show(msg);
Close();
}
}
}
Your dataTypeKey and ACTFCSTtext variables need to be declared as instance variables for your Form object if you want to access them from any other methods within your form. If you want to use them with some other form, you can pass them either as constructor arguments, or set some properties of said other form.
So you'd declare them just after the class declaration if you want them to be instance variables. They should still be private, meaning they can only be accessed from within your frmLoadACTFCST class.
public partial class frmLoadACTFCST : Form
{
private string ACTFCSTtext = "";
private int dataTypeKey = 0;
...
EDIT: if you want to access variables from one object in a different object (or static class), your options are as follows...
1) Declare your variables as public instance variables (same as shown above but public; these are known as Properties when you give them getter and setter methods). Your class that needs access to these variables would need to have a reference to the class that owns the variables.
Example:
FormA has a public property named SomeString.
FormB needs to access SomeString.
FormB needs a reference to FormA, and would access the variable as...
formAReference.SomeString
2) Pass the values of the variables as arguments to some method for the class that needs access.
Example:
FormA has a private instance variable named SomeString.
FormB needs access to SomeString.
If FormA instantiates FormB, it can pass the value of SomeString to FormB's constructor...
//From within FormA's code
FormB formB = new FormB(SomeString);
//FormB's constructor
public FormB(string someString)
{
this.someString = someString;
}
Maybe there is a smarter way to do it.
public partial class frmLoadACTFCST : Form
{
public frmLoadACTFCST()
{
InitializeComponent();
actfcst = ACTFCST.ACT;
btnActual.Tag = ACTFCST.ACT;
btnActual.Checked = true;
btnForecast.Tag = ACTFCST.FCST;
btnPlan.Tag = ACTFSCT.PLAN;
btn5YrPlan2012.Tag = ACTFCST.FiveYearPlan2012;
}
public enum ACTFCST
{
ACT = 1,
FCST = 2,
PLAN = 3,
FiveYearPlan2012=4
}
public static ACTFCST actfcst { get; private set; }
private void CheckedChanged(object sender, EventArgs e)
{
// All the buttons uses this Click-event.
actfcst = (sender as Button).Tag as ACTFCST;
}
private void btnContinue_Click(object sender, EventArgs e)
{
MessageBox.Show(actfcst.ToString());
Close();
}
}
The point is that all the buttons calls CheckedChanged when clicked.
Using a static means that others can access the value using something like this:
frmLoadACTFCST.ACTFCST value = frmLoadACTFCST.actfcst;
// Do something based on value.
I hope this helps you in yoyr quest.
If you select a control in design view, the properties window contains an item named "Modifiers". You can make the control public here.
A better way would be to create a new public property on your form that yields the value of the currently selected radio button.
I have a listbox full of items for my order.
I want to take all of the items inside my listbox and transfer them into my listview.
Then I want to take my listview and display it in another form (my messagebox).
My new listview:
private void CustomerInfo_Click(object sender, EventArgs e)
{
ListViewItem customers = new ListViewItem(fullName.Text);
customers.SubItems.Add(totalcount.ToString());
customers.SubItems.Add(total.ToString());
customers.SubItems.Add(Address.Text);
customers.SubItems.Add(telephone.Text);
for (int i = 0; i < OrderlistBox.Items.Count; i++)
{
customers.SubItems.Add(OrderlistBox.Items[i].ToString());
}
Customers.Items.Add(customers);
//CLEAR ALL FIELDS
OrderlistBox.Items.Clear();
fullName.Text = "";
Address.Text = "";
telephone.Text = "";
totalDue.Text = "";
totalItems.Text = "";
}
My contextMenuStrip, so when I click on the customer I can get its info (name, address, order, etc.):
private void customerInformationToolStripMenuItem_Click(object sender, EventArgs e)
{
if (Customers.SelectedItems.Count != 0)
{
var myformmessagedialog = new MessageBoxForm
{
name = Customers.SelectedItems[0].SubItems[0].Text,
address = Customers.SelectedItems[0].SubItems[3].Text,
telephone = Customers.SelectedItems[0].SubItems[4].Text,
};
myformmessagedialog.ShowDialog();
}
}
My new form, the messagebox where I will display all the info for the client:
public partial class MessageBoxForm : Form
{
public MessageBoxForm()
{
InitializeComponent();
}
public string name;
public string address;
public string telephone;
public ListViewItem order = new ListViewItem();
private void MessageBoxForm_Load(object sender, EventArgs e)
{
lblName.Text = name;
lbladdress.Text = address;
lbltelephone.Text = telephone;
orderListView.Items.Add(order);
}
}
I'm sorry if this seems confusing but I'm just looking for help to go in the right direction. Any help is appreciated.
One way to do this is to put the data that you want to display in some sort of ViewModel, basically a class or set of classes that has the data that you want to display. Then the main form can display it, and you can pass a reference to that ViewModel to the message box and it can display it as well.
In general you want to avoid any kind of code that directly ties controls from different forms together.
The easiest way based on your current setup is to simply pass your list view data across to your MessageBoxForm e.g.
public partial class MessageBoxForm : Form
{
...
public void LoadListView(ListViewItemCollection items)
{
orderListView.Clear();
orderListView.AddRange(items);
}
}
....
private void customerInformationToolStripMenuItem_Click(object sender, EventArgs e)
{
if (Customers.SelectedItems.Count != 0)
{
var myformmessagedialog = new MessageBoxForm
{
name = Customers.SelectedItems[0].SubItems[0].Text,
address = Customers.SelectedItems[0].SubItems[3].Text,
telephone = Customers.SelectedItems[0].SubItems[4].Text,
};
myformmessagedialog.LoadListView(Customers.Items);
myformmessagedialog.ShowDialog();
}
}
Basic answer is you don't.
You maintain a collection of items (whatever they are).
You display them in a list box.
You display them in a list view.
If you want say select some from the list box and only move them to the list view.
Then you use the listbox selection to find them in your collections of items, create a list of selected ones then passs that to the form with the listview to display.
Don't use UI controls to store your data and try really hard to never make one form's UI directly dependant on another.
I'm guessing what you'd need (and I could have misunderstood what you are looking for) is a new method in you MessageBoxForm to pass in your Customers object:
private void customerInformationToolStripMenuItem_Click(object sender, EventArgs e)
{
if (Customers.SelectedItems.Count != 0)
{
var myformmessagedialog = new MessageBoxForm;
myformmessagedialog.Customers = Customers;
if (myformmessagedialog.ShowDialog() == DialogResult.OK)
{
Customers = myformmessagedialog.Customers;
}
}
}
If so, simply modify your class to be something like this:
public partial class MessageBoxForm : Form
{
public MessageBoxForm()
{
InitializeComponent();
}
private void MessageBoxForm_Load(object sender, EventArgs e)
{
if (Customers != null)
{
// add your code here to add your Customers as needed
}
}
public Customers Customers { get; set; }
}
To access anything from the parent form you need to pass it to the child form so
myformmessagedialog.ShowDialog();
becomes
myformmessagedialog dialog = new myformmessagedialg(this);
dialog.ShowDialog();
and your class constructor becomes this:
public MessageBoxForm(myformmessagedialog parent){
name=parent.fullName.Text;
address=parent.address.Text;
...etc...
InitializeComponent();
}
Though it might be better to just pass in the name, address, etc rather than the whole form, this way is nice for while you are changing things because you have one less place to change to add another variable to pass.