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Properties of Webusercontrols

I have a question and I can not find the right terms to do a reasoned search and solve the question.
Let's see, when I'm creating a page, at some point I need to create a WebUserControl and defer something like state = "true" (like the text of the lables) inside the html tag so that as soon as the page loads , Whether or not that control is subsequently edited in code.
<MyControls:Teste Id="aaa" runat="server" state="false"/>
The test control code is as follows: (The HTML page of this control is blank, it only has the header)
public partial class WebUserControls_WUC_Tect : System.Web.UI.UserControl
{
private static bool state ;
public bool State
{
get { return state ; }
set { state = value; }
}
protected void Page_Load(object sender, EventArgs e)
{
}
}
Problem:
Whenever the page returns to the server and is reloaded, the state variable is always set to false or true depending on the initial state I passed, what I intended was for this variable to be loaded only once at the beginning of the page and then Could only be changed by codebeind.
I am grateful for your suggestions.
greetings
Patrick Veiga

You need to use the ViewState to store the property value to keep the persistent value saved.
public partial class WebUserControls_WUC_Tect : System.Web.UI.UserControl
{
private static bool state ;
public bool State
{
get
{
if (ViewState["MyState"] == null)
{
ViewState["MyState"] = false;
}
return (bool)ViewState["MyState"];
}
set
{
ViewState["MyState"] = value;
}
}
protected void Page_Load(object sender, EventArgs e)
{
}
}

WP8 determining page navigation history

In my windows phone 8 app, I am navigating among pages. say
From MainPage(some user control a click to) -> Page1 then with a key press it will take me to main page back again
From MainPage(some user control b click to) -> Page2 and then back with the key press to main page again and so on to page3, page4 etc.
Here I want to identify from which page the main page is loaded from?
Say page1, page2 or page3 based on that I want to load the user controls according to navigation history.
I could not found any built-in property or function in a library.
Any help, I am looking for best practice as well to achieve such functionality.

You can use back stack for this kind of purposes.
How to navigate using the back stack for Windows Phone
See also:
https://stackoverflow.com/a/7000977/942286

make hashtable global.
Hashtable ht = new Hashtable();
ht.Add("page1");
NavigationService.Navigate(new Uri("Page1.xaml", UriKind.Relative));

You can create an
enum PageType
{
NONE,
PAGE_1,
PAGE_2,
PAGE_3,
PAGE_4
}
Then in your MainPage you can have a ivar as
private PageType pageType = PageType.NONE;
Then when you move to a page you can set it
pageType = PageType.PAGE_!;
NavigationService.Navigate(new Uri("Page1.xaml", UriKind.Relative));
and when you come back to MainPage then you can have this
protected override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
if (e.NavigationMode == NavigationMode.Back)
{
switch (pageType)
{
case PageType.NONE:
//Your code
break;
case PageType.PAGE_1:
//Your code
break;
case PageType.PAGE_2:
//Your code
break;
case PageType.PAGE_3:
//Your code
break;
case PageType.PAGE_4:
//Your code
break;
}
}
}
EDIT
You can then use navigation context.
In your user control
NavigationService.Navigate(new Uri("Page1.xaml?PAGE_TYPE=Page1", UriKind.Relative));
In your MainPage
protected override void OnNavigatedTo(NavigationEventArgs e)
{
base.OnNavigatedTo(e);
if (e.NavigationMode == NavigationMode.Back)
{
String pageType = null;
NavigationContext.QueryString.TryGetValue("PAGE_TYPE", out pageType);
if (pageType == "Page1")
{
//Your code
}
}
}

If you must know what page you came from, you can use PhoneApplicationService.Current.State. Within your secondary pages, override OnBackKeyPress and set the value
protected override void OnBackKeyPress(System.ComponentModel.CancelEventArgs e)
{
base.OnBackKeyPress(e);
PhoneApplicationService.Current.State["LastPage"] = this;
}
Then in the MainPage, you would override OnNavigatedTo and check the value of the state
protected override void OnNavigatedTo(NavigationEventArgs e)
{
object lastPage;
if((e.NavigationMode == NavigationMode.Back) &&
(PhoneApplicationService.Current.State.TryGetValue("LastPage", out lastPage)))
{
// we navigated back and we know what the last page was!
var pageName = lastPage.GetType().Name;
if (pageName == "Page1")
{
// do something!
}
}
}

Just pass parameters when you are navigating back to main page, maybe an enum type contains 'page1' 'page2' ...

It seems that the NavigationService doesn't contain the information you need, as well as the NavigatingCancelEventArgs parameter coming with OnNavigatingFrom.
So unfortunately, it seems there's no builtin feature addressing your need.
However , what you could do is to persist the last page your user has been (to handle tombstoning scenarios). For instance it could be in AppSettings, here is a pseudo code :
public class WhateverYouWantLastPagePersister
{
private const string LastPageID = "LastPage";
public string GetLastPage()
{
string lastPage = string.Empty;
IsolatedStorageSettings.ApplicationSettings.TryGetValue<string>(LastPageID, out lastPage);
return lastPage;
}
public void PersistLastPage(string lastPage)
{
IsolatedStorageSettings.ApplicationSettings[LastPageID] = lastPage;
}
}
To persist "automatically" your last visited page, you can derive from PhoneApplicationPage and override OnNavigatingFrom to create a your own base page :
public class BasePage : PhoneApplicationPage
{
protected override void OnNavigatedFrom(NavigationEventArgs e)
{
base.OnNavigatedFrom(e);
Uri currentUri = ((App)Application.Current).RootFrame.CurrentSource;
WhateverYouWantLastPagePersister.PersistLastPage(CustomMethodToExtractPageNameFromUri(currentUri));
}
}
All pages needing to persist the last visited pages have to derived from it (so Page1, Page2...)
Finally you can use WhateverYouWantLastPagePersister.GetLastPage() to get what you need.
Of course, in these pseudo code samples :
lastPage can be of any type you want (string, enum , int and so
on...), you just need an appropriate custom converter from string to anything you want
CustomMethodToExtractPageNameFromUri is a simple string parser
WhateverYouWantLastPagePersister can be static class, a singleton, injected with a DI framework, it's up to you!

How can I take items from a listbox and display them in a listview in another form?

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.

Is there a way to clear the Navigation Service or not register a frame?

I'm developing an aplication for Windows 7, and I need to block a page.. my solutions are not register that frame or clear all the frames in back.

Guessing that you mean you have a page on the Back-stack that you want to remove --
In the new Mango SDK, there's a Method you can try NavigationService.RemoveBackEntry
However it might be easier to just use a boolean and check in OnNavigatedTo:
At page where you need to go back > 1 pages:
in App.xaml.cs:
public static bool IsBackwardNavigation = false;
public static string PageContext = string.Empty;
Page2.xaml.cs :
public void YourFunction()
{
App.PageContext = "MainPage";
App.IsBackwardNavigation = true;
if (NavigationService.CanGoBack)
NavigationService.GoBack();
}
And in each page's OnNavigatedTo:
Page1.xaml.cs:
string Page1 = "Page1";
protected override void OnNavigatedTo(object sender, NavigationEventArgs e)
{
if (App.IsBackwardNavigation)
{
if (!Page1.Equals(App.NavigationContext)
{
//since this page's name is not the correct page, the page will go back again.
if (NavigationService.CanGoBack)
NavigationService.GoBack();
}
else
{
//this is the page we're trying to get to
App.IsBackwardNavigation = false;
App.NavigationContext = string.Empty;
}
}
}
}

Linking a Text Box to a variable?

I would like to have direct access to the text inside a textbox on another form, so I added a public variable _txt to a form and added an event like so:
private void richTextBox1_TextChanged(object sender, EventArgs e)
{
_txt = richTextBox1.Text;
}
But the form is loaded like this:
public FrmTextChild(string text)
{
InitializeComponent();
_txt = text;
richTextBox1.Text = _txt;
Text = "Untitled.txt";
}
Is there a better way to directly link the two?

You could use a property instead to read directly from your TextBox. That way you don't need an extra variable at all.
public string Text
{
get
{
return richTextBox1.Text;
}
}
Add a setter if you also want to be able to change the text.

I don't think you should ever have forms reference each other's controls: when you change the lay out of one you will have to rewrite the code for the other. It is much better IMHO to store shared values in a separate class and have both forms reference that. Like so:
public class DataContainer
{
public string SomeData{get;set;}
}
public class Form1:Form
{
private DataContainer _container;
public Form1(DataContainer container)
{
_container=container;
}
private void richTextBox1_TextChanged(object sender, EventArgs e)
{
_container.SomeData = richTextBox1.Text;
}
private void SpawnForm2()
{
var form2=new Form2(_container);
form2.Show();
}
public class Form2:Form
{
private DataContainer _container;
public Form2(DataContainer container)
{
_container=container;
}
}

Another way to do it would be setting the Modifiers property for the TextBox (or any other control you want to access) to Protected Internal and then open the second form, the Owner being the first form.
This way, you can later on access the control and its properties with something like this:
((Form1)this.Owner).textBox1.Text = "This is a message from the second form";