c# win forms

Question

Is it possible to do this:
Form6 form6 = new Form6();
in a form in a windows application and then do this
form6.listview1.Items.Add(lv1);
directly in another form in the same application?
Tried it, but it does not work, any other way to work this out?

stvb2nu · Answer

hi to all...
i'm a newbie in c#. i'm currently doing an application for our school Internet Lab. I 've created a form winForm1 with a Listview control on it.. then i've created another form winForm2 with a combobox on it. whenever winForm2 loads, student username fills the comboBox. my problem is, how will i pass a value from the comboBox to the listView control in winForm1? i've already tried some code from the other forums but it wont work. i've already made the listview in winForm1 PUBLIC. please help...
thanks..

steven_yin · Answer

you cant do this,for listview1 is private?

mdlardizabal · Answer

One quick question, have you considered using MDI forms instead?
If not then either you start considering using MDI or build a mechanism similar to MDI parent-child relationships.
The main principle is to create a static list most likely an arraylist that will contain references to any open form. If one form wants to access another form it has to traverse the list.
You would need to build a parent form to hold the list, it doesn't have to be visible all the time or not at all.
Pick which path and we can help you either way, I hope hehehe...
Hanggang sa muli,
Tikbalang

rmtielman · Answer

Actually there are more than 3 forms involved in it.
the middle form is used to select from the combo and fill up the listbox.
and when u add to the listbox the form remains hidden, only in the end that it is supposed to display the list of items listed.
However from the middle form u can go back to other forms to update the combo to appropriate values from the db.(so that I have to reload the middle form all the time which means that a new form with the list will be instantiated each time u add something)
The problem is how d'u make the compiler know that the last form(say frmx) is already instantiated.
Coz unless u do 'frmx frm = new frmx();', the compiler cannot find it.(but the form has to be instantiated the first time though)
Sorry for all the misunderstandings, am a little bit new to all this :S. n thks for the replies.

garymorris · Answer

I'm a little confused myself on what exactly you are asking for,
but I've seen a lot of questions like this and I had a similar
situation. Now, if you have, say, a form Form1, and you need
to open a second form, Form2, that can access Form1, here is
what I would do:
In Form2 I'd create a Form field, like
Form frm1 = new Form();
Then, I would overload the constructor of Form2 with a Form
parameter like
public Form2(Form passedForm)
{
frm1 = passedForm;
}
Then, when calling Form2 from Form1, I'd just say
Form frm2 = new Form2(this);
That way, Form2 gets passed the CURRENT instance of Form1
and can access anything that exists in Form1.
From there it's a simple thing to say frm2.listview......
or whatever.
That is, IF I read this right. If not, let us know.

mdlardizabal · Answer

Hmmm I'm confused bare with me pls =)
If Form6 is not instantiated why update its properties?
Or are you trying something like this:
You have Form6 open, then you click something Form1 opens, and then you change something on a textbox you want those changes forwarded back to Form6 ListView?
If you were doing the above scenarion here is what I suggest:
1. You can create a property in Form1 called MyParent and make it type Form6.
2. When you open Form1 assign MyParent the "this" to reference the current object.
so something like
// form6
Form1 f1 = new Form1();
f1.MyParent = this;
//form1
this.MyParent.ListView.Clear();
or something like that.
Hope that helps. I was assuming, so if you had something different in mind please correct me right away.
Hanggang sa muli,
Tikbalang

rmtielman · Answer

Yea, I had made the listview public, the problem is with the form6. the compiler could not find it coz I did not create an instance for it.
How can u create that instance in another form and still access it in this one?

mdlardizabal · Answer

I'm sorry I was a bit vague.
On your code on Form6
public class Form6 : System.Windows.Forms.Form
{
...
private System.Windows.Forms.ListView listView1;
....
}
change it to
public class Form6 : System.Windows.Forms.Form
{
...
public System.Windows.Forms.ListView listView1;
....
}

mdlardizabal · Answer

Hi,
Have you tried making the listview1 object of Form6 public?
Hanggang sa muli,
Tikbalang