add child's form closing event #2

George Paroglou

Vulpes as far it concerns tabs name update: the reason that I am thinking such a thing is because I want to assign in the same tab string a new tabpage without closing the initial one. For a single user this will be as from the initial tabpage it goes to a new tabpage by using the same tab and not opening a new one. Something like the categories of running applications in windows( not the same thought). That's why I mentioned to update tabs name.

Do you think is it possible?

P.S. I opened a new thread cause the initial one prints an error. ( http://www.c-sharpcorner.com/Forums/Thread/118328/add-childs-form-closing-event.aspx )

25 Replies

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Vulpes15y ago
Sorry, Focus is a method rather than a property so in C# it needs to be tp.Focus() rather than tp.Focus which VB allows if a method takes no arguments.

The fields should be placed near the top of the form class:

class Form1 : Form
{

private TabPage TempTab;
private int TempTabIndex;

// rest of form code
}
George Paroglou15y ago
vulpes why in the first snippet it signs tp.focus as an error ( Cannot convert method group 'Focus' to no-delegate type 'bool' )?

these fields ( private TabPage TempTab; private int TempTabIndex; ) I have to add them where?

I am trying to add the code of the first snippet inside my toolStripButton2_Click...
Vulpes15y ago
Sure, George. It's a manual conversion as I never use translators:

// first snippet

private void button3_Click(object sender, EventArgs e)
{
// Identify the TabPage to be removed
foreach(TabPage tp in this.tabControl1.TabPages)
{
if(tp.Focus)
{
TempTab = tp;
tabControl1.TabPages.Remove(tp);
break;
}
}
}

// second snippet

tabControl1.TabPages.Add(TempTab);

// third snippet

// Identify the Index Number of the selected TabPage
for(int i = 0; i < tabControl1.TabPages.Count; i++)
{
if(tabControl1.TabPages[i].Focus)
{
// Save the details of this TabPage
TempTab = tabControl1.TabPages[i];
// Save its index number
TempTabIndex = i;
// Remove it
tabControl1.TabPages.RemoveAt(i);
// Stop looking for Tabpages with Focus
break;
}
}

// fourth snippet

private button6_Click(object sender, EventArgs e)
{

//Reinsert TabPage in correct position
tabControl1.TabPages.Insert(TempTabIndex, TempTab);
}

You'll also need to add these fields to your form:

private TabPage TempTab;
private int TempTabIndex;
George Paroglou15y ago
You are right...I am not confortable with tag because I couldn't find out how this could be called back after tab's creation.

Vulpe can you please convert for me the codes of the second article from vb to c#?
Vulpes15y ago
George, did you look at the second part of the article (http://blogs.vbcity.com/xtab/archive/2007/06/29/8473.aspx) and also, though it may not be relevant, the third part (http://blogs.vbcity.com/xtab/archive/2007/07/18/8508.aspx)?

You can probably stick to using the Name property with this approach as you never seemed comfortable with using the Tag property instead.
George Paroglou15y ago
during this hide/show proccesses how can I use the correct childtab in order to do so and how can I give the same string context in the new tab/tabpage?
Vulpes15y ago
Yes, I don't see why not.

As explained in the article, the key is to save the TabPage to a temporary field before you remove it from the TabPages collection. You can then restore it to its previous position with all its controls still in tact.
George Paroglou15y ago
It does have a tabpage open and a tab and I am trying to make the new form to be a member of the initial opened tab and on top of the already opened tabpage

I found this example in vb ( http://blogs.vbcity.com/xtab/archive/2007/06/25/8465.aspx)

Do you think it could be done to hide the old tabpage and its tab and open a new one in the same place at it was? and If later on I want to go back to the hidden tab-tabpage just show() it?

I am thinking and the possiblity of overloading either pc's proccess power or memory's capacity....
Vulpes15y ago
Well, I don't know what you're expecting me to say, George, as the example code which you've pasted in from my earlier post appears to have nothing to do with the rest of the code.

I have no idea whether tabControl1 has any TabPages at that stage or not.
George Paroglou15y ago
Vulpes I added the sample code you gave me but still nothing. I attatched the code for a review.
George Paroglou15y ago
i c Vulpes... and how I can assign the new opened form with the specific tabpage (and tab) and be controlled as part of them? I mean to be on top of the proccessed tabpage and make its tab to print a new name?

what do you suggest I should do to assign the new proccess form to the tabpage,tab?
Vulpes15y ago
Just assign a suitable value to the Tag property whenever you create a new TabPage.

I think it would have been better if you'd used the Tag property from the outset rather than the Name property to achieve tab and TabPage synchronization because doing so has no implications for the indexing of the TabPages collection. You can change it now if you like but I don't think it will solve the previous problem which probably has nothing to do with what the TabPages are called but has some other (as yet unexplained) cause.
George Paroglou15y ago
and the rest bits of codes (for loop and if statement) should be added in the new's form(tabpage) opening event I guess right?

At the very beginning I was trying to make this tab and tabpage synchronization by using a code with key assignment.... do you think this should be the appropriate way of initially create the tabs and their tabpages or do you suggest to leave them with the text name assignment and just add the tag
Vulpes15y ago
The only place I can see where you're creating a TabPage is in the linkLabel1_DoubleClick method:

public void linkLabel1_DoubleClick(object sender, EventArgs e)
{
Spoudastes_Form sc = new Spoudastes_Form(); //add new child
TabPage childTab = new TabPage(); //create new tab page
sc.MdiParent = this; //set as child of this form
sc.Name = "People Data " + createdTab.ToString();
sc.Text = "People Data " /*+ createdTab.ToString() */;
childTab.Name = sc.Name;
childTab.Tag = createdTab;
//make sure name and text are same
childTab.Text = "People Data ";// +createdTab.ToString();
//this is for synchronize later
tabControl1.TabPages.Add(childTab); //add new tab
tabControl1.Visible = true;
sc.richTextBox1.Parent = childTab; //attach to tab
ToolStripMenuItem newMenuTab = new ToolStripMenuItem(); //create menu to hold tab
newMenuTab.Text = sc.Text; //make sure the name and text are same to synchronize later
newMenuTab.Name = sc.Name;
mnuTab.DropDownItems.Add(newMenuTab); //add menu item
newMenuTab.Click += new EventHandler(newMenuTab_Click); //add event handler
tabControl1.SelectTab(childTab); //this is to make sure that tab page is selected in the same time
sc.Show(); //as new form created so that corresponding tab and child form is active
sc.Dock = DockStyle.Fill;

createdTab++; //increment of course

toolStripButton2.Visible = true;

Spoudastes_Form childForm = (Spoudastes_Form)this.ActiveMdiChild; //this is the reason
//why synchronization between tab and active MDI child is important
}

BTW, I didn't make this suggestion with a view to solving the previous problem (which is inexplicable) but as a way to facilitate the new stuff that you were talking of doing.
George Paroglou15y ago
Vulpes can you please add it in the attatched code? I tried to put somewhere inside the the first bit of your code and again the synchronization between the x tab button and the x button of tabpage is off
Vulpes15y ago
Well, you'll need a Tag property for every TabPage (there's no default) so I'd add code which sets one from the initial setup and then when each new TabPage is created.
George Paroglou15y ago
do you suggest to replace the initial tabcontrols structure(from the point of opening each tab) or it can be done as soon as the need of s new tabpage is present?
Vulpes15y ago
Sure, this code would set a TabPage's Tag property to its index in the TabPages collection:

for(int i = 0; i < tabControl1.TabPages.Count; i++)
{
tabControl1.TabPages[i].Tag = i;
}

To find the TabPage with a Tag property of 2, you'd then do:

TabPage findPage = null;

for(int i = 0; i < tabControl1.TabPages.Count; i++)
{
int j = (int)tabControl1.TabPages[i].Tag; // cast needed as Tag is stored as type object
if (j == 2)
{
findPage = tabControl1.TabPages[i];
break;
}
}

if (findPage != null)
{
// do something with findPage
}

or, if there may be duplicate TabPages with a Tag of 1, you could do:

List listPages = new List();

for(int i = 0; i < tabControl1.TabPages.Count; i++)
{
int j = (int)tabControl1.TabPages[i].Tag;
if (j == 1) listPages.Add(tabControl1.TabPages[i]);
}

if (listPages.Count > 0)
{
foreach(TabPage page in listPages)
{
// do something with page
}
}
George Paroglou15y ago
what do you mean to use the tag property? I am trying to understand it but something is missing. give me please a code example of how this can be done with tag propery and not with tag name text.
Vulpes15y ago
I'm talking here about the Tag (not Tab) property which is a property which all controls have and which allows you associate some object (it can be a number, string or something else) with a particular control.

In particular, you can use the Tag property (rather than the Name property) to distinguish between instances of the same control. This has the advantage of not affecting the indexing of the controls within their container's Controls collection and also means you can use duplicate tags if you want.
George Paroglou15y ago
I am attatching the code that we concluded for just the opening and closing event for each tab and tabpage.

What do you mean when saying tab property?
Vulpes15y ago
As I can't remember much now about the original thread (still inaccessible), I only have a vague idea of what you're talking about.

However, my instinct is not to change the Name property but to change the Tag property of the TabPage instead because that shouldn't upset anything else and it won't matter if it's duplicated.
George Paroglou15y ago
any clue vulpes?
George Paroglou15y ago
and what about the situation of having two or more opened tabpages with its tabs and all of them be in the same point of proccess? (i.e. in the second opened tabpage all of them). I think you got my point. I am trying to make each tab a completely separate action and the only common will be only their certain possition.

To explain you the proccess, it is the field that user specifies the text of his search and then the second tabpage assigned is a dataset (or datagridview) that outputs the results of his search. This output is the one I am trying to handle correctly. It may have more than two depending on user's steps. Each step and propably a new tabpage with the same tab but with an updated tab's name.

I tried and open this dataset output but of course is not assigned with its first tabpage tab.
Vulpes15y ago
Well, I'd try it and see.

What you will need to be careful with is the TabPages collection because this is indexed by the name of the TabPage as well as by the order in which they are added to the collection. So, you certainly don't want there to be more than one TabPage with the same name at any point in time.