Is it possible to acces a control thats located in a content page (withing a content place holder, a multiview control to be more exactp) from the master page?
The situation is, i have a menu with buttons thats located in the master page.
Now in my content page i have 1 content place holder.
In which a multiview with several views is located.
If i press a button in the menu (MasterPage) then it should open the proper view (with its controls) displayed in the content place holder area.
I have set the ActieveViewIndex=0 but i am getting all sorts of wierd behavour.
I have to do something with the ActiveViewIndex++ somewhere but nothing seems to work.
edit::
string a = Request.Querystring["one"]
string b = Request.QueryString["two"]
if ( a == "addOne") // where addone is a redirection to the content page from the master page button
{
mvMultieView.SetActiveView(vView1);
}
else
if ( b == "addTwo")
{
mvMultieView.SetActiveView(vView2);
}
Any suggestions?
Kind Regards.
You can easily do that using find control
View myView = (View)this.Master.FindControl("PlaceHolderFullMain").FindControl("PlaceHolderMain").FindControl("Mymultiview")
The way my team and I accomplished this task (and I don't know that it's the best method, but it was effective) was to use query strings (as you had in your previous question it looks like). We established a standard QS variable called iView that would determine the name of the view in question (not necessarily the control name itself, but some keyword that the content control would respond to). Since all of our pages/controls have a page base class they inherit from, we put a method in the base class (in our case it was at the page level, but in yours a control level might work) that was responsible for getting the requested view. In the control we would have a mechanism (switch perhaps) that would set the activeView. In some cases we just used the actual ID of the control (since it was a mystery to be obfuscated) and avoided the switch altogether.
http://www.mydomain.com/mypage.com?iView=mySecondView
partial class MyControl : System.Web.UI.WebControl
{
// blah blah control stuff
public string getRequestedView()
{
return (Request.QueryString["iView"]) ? Request.QueryString["iView"] : String.Empty;
}
}
...
protected void Page_Load(object sender, EventArgs e)
{
View myView = myMultiView.FindControl(this.getRequestedView());
if(myView != null)
this.MyView.SetActiveView(myView);
}
have you done this change in the Master page or content page?
because i also got the same problem.
I have link buttons in my master page which i need to activate view controls in content page.
the content page is not the currently loaded page.
will this method help for my solution?
Related
Okay, so we all know about changing a master page dynamically in a page's OnPreInit event.
But what about a nested master page? Can I change a master's master?
There is no OnPreInit event exposed in the MasterPage class.
Any ideas?
Just tested this and it works from the PreInit of the Page that is using the nested MasterPage.
protected void Page_PreInit(object sender, EventArgs e)
{
this.Master.MasterPageFile = "/Site2.Master";
}
Obviously you will need to ensure that the ContentPlaceholderIds are consistent across the pages you are swapping between.
We combine Andy's method with a "BasePage" class - we create a class that inherits from System.Web.UI.Page, and then all our pages inherit from this class.
Then, in our base page class, we can perform the relevant checks to see which root master page should be used - in our case we have a "Presentation" master, and an "Authoring" master - the presentation version has all the navigation and page furniture, along with heavy display CSS, while the authoring master has some extra JS for the authoring tools, lighter CSS, and no navigation (it's what we use when the user is actually authoring a page, rather than modifying the site layout).
This base page can then call Page.Master.MasterPageFile and set it to the Authoring master if that is the correct state for the page.
Just in case anyone stumbles across this and tears their hair out with a "Content controls have to be top-level controls in a content page or a nested master page that references a master page" error when trying Andy's code, get rid of the this.Master. So, the code becomes:
protected void Page_PreInit(object sender, EventArgs e)
{
MasterPageFile = "/Site2.Master";
}
Edit As Zhaph points out below, the code I have ^^ there will only change the current page's master, not the master's master. This is the code Hainesy was talking about when he mentioned "we all know about changing a master page dynamically" (which I didn't, d'oh). If you happen to get to this page by googling "stackoverflow change master page" (which is what I did) then this is possibly the code you're looking for :-)
To add on to the answer of Zhaph - Ben Duguid, (+1 by the way):
Here is example code that sets the master page of the nested master page. All pages inherit from this BasePage, so this code only exists in one place.
public class BasePage : System.Web.UI.Page
{
private void Page_PreInit(object sender, System.EventArgs e)
{
if (Request.Browser.IsMobileDevice)
{
if (Page.MasterPageFile == "~/master/nested.master"))
{
Page.Master.MasterPageFile = "~/master/mobile.master";
}
else
{
MasterPageFile = "~/master/mobile.master";
}
}
}
}
I have Main.Master, an inner master page Inner.Master, and abc.aspx. In Inner.Master I have a dropdownlist ddlChildren which I populate on Inner.Master page load.
I would like to, on loading page abc.aspx, I get access to ddlChildren from its master page, Inner.Master:
int x = Int32.Parse(((DropDownList)this.Parent.FindControl("ddlChildren")).SelectedValue);
I am doing this on page load of abc.aspx. The problem is this control is not found. I think this happens becuase the control is not even loaded yet in Inner.Master, because when I do:
this.Parent.Controls.Count
at debugging, I only have 1 control for Inner.Master, which its Main.Master.
I then tried to call ddlChildren onPreRender, but the same Happens.
According to http://msdn.microsoft.com/en-us/library/ms178472.aspx, controls are loaded at pre render, but the on pre render of inner master is called AFTER abc.aspx. So can I do this at another page stage?
Or am I completely off track?
Visual breakdown of the lifecycle, including master pages.
OK, I think there is more going on here.
First of all FindControl isn't recursive, unless what you are looking for is a direct child of the object in question, you won't find it.
You'll need a function something like this (not tested, but I've written something like it before):
private WebControl FindControlRecursive(WebControl parentControl, string controlId)
{
if( !parentControl.Controls.Any())
return null;
var foundControl = parentControl.FindControl(controlId);
if(foundControl == null)
{
foreach(child in parentControl.Controls)
{
var foundChild = FindControlRecursive(child, controlId);
if(foundChild != null)
return foundChild;
}
}
return foundControl;
}
Second, you're assuming Parent of your page is the master page. This may not be true. Try Page.MasterPage detailed here.
So, to conclude, try this:
var dropDown = (DropDownList)FindControlRecursive(Page.MasterPage, "ddlChildren");
One more thing. It's usually good to consider that if you find yourself accessing controls that exist in a level above your current Page scope, you may want to rethink your design.
How to Access Controls from UserControls in ASPX page?
For example:
I want to access gridview which is in usercontrol on ASPX page.
Please help me.
Try this :
GridView GridView1 = (GridView)WebUserControl1.FindControl("GridView1");
Where WebUserControl1 is ID of use control on .aspx page.
Hope this helps..
The best way is to provide properties in your UserControl that you can access.
For example:
public GridView UserGrid
{
get
{
return GridView1;
}
}
But the question is why you need this.
Rule of thumb: Only expose as few as possible. On that way your code will be most robust and readable. So it would e.g. better to expose it's DataSource rather than the complete GridView.
On the other hand, if you want your page to react on events in your UserControl, it should provide custom events(e.g. UserDeleted) that your page then can handle.
Page-UserControl-Commmunication
Because the controls now nothing about eachother at the same level, you have to use the parent page to get it. Try this logic:
Create a property referring to your parent page (the page your control usually is in (might be different because of layering of controls)
Create a property on your page referring to the usercontrol the grid is in, or link to that grid directly.
page.aspx
public UserControl UserGridControl
{
get;
set;
}
userControl.ascx
public Page ParentPage
{
get;
set;
}
Example call:
Instantiate the properties first. After that, use the following statement to access anything from that control (as an example I used Foo() here, to use as a dummy method, but it seems it was unclear to someone):
otherControl.ascx:
this.ParentPage.UserGridControl.Foo();
EDIT: Want to have a direct code example to be able do it from the page only? See Tim Schmelters answer. If you need a way to call the grid from another user control as well. Use mine.
I am using a user control that I created (just a .cs file not an .ascx file), that does some magic and depending on a value generated by the control, I need it to do something on the parent page that is 'hosting' the control. It needs to call a method under certain circumstances (method is on the parent control).
the control is placed on the parent page like so:
<customtag:MyControl ID="something" runat="server" />
I'm dynamically creating buttons etc on the control itself but when a button is clicked, let's say for example that there's a text box on the control and if the value of the textbox is "bob" it needs to call a method on the page that's housing the control...how can I accomplish this?
You could do what casperOne suggested, but I wouldn't advise it. This is tightly coupling your user control to your parent page, which kind of defeats the purpose of a user control.
Personally, I'd add an event to the user control (say, ButtonClicked) that the parent page can handle. In the event handler in your parent, deal with the event however you see fit. This way you can plug the user control into a different page at a later date and not have to worry about logic in the user control that requires a specific kind of parent page.
You should be able to get the Page hosting the control through the Parent property. However, that's going to be returned to you as a Control. You have to cast it to the type of your page in order to access any methods on the page which you have defined.
I think that casperOne is on the right track, but you need to go a step further. I'm giong to make the assumption that this user control will be used on more then on page. (I normally write VB.Net, sorry if my C# is malformed)
Make a base page class (you can store it in your App_Code directory or in a project):
public class PageToInheritFrom : System.Web.UI.Page {
public void SpecialFunction() {
}
}
Now make sure that all of your pages inherit from this page in your code behind file:
public partial class _Default : PageToInheritFrom {
}
Now in your user control you know what the page type is and can call
((PageToInheritFrom)this.Page).SpecialFunction();
I'm trying to make a default modal box that must be accessible from any part of the application, and need to be called whenever I want from inside any page. (must be called from code-behind).
So I came up with the idea of a Panel + modalPopupExtender placed in the MasterPage, and calling it from child pages via code-behind.
How can I do that? Or perhaps you guys have a better idea to solve this.
Since the modal is to be called from the code behind, you can achieve it like this
Add a method to your Master Page
public class MyMaster : MasterPage
{
public void ShowModal(string someParameter)
{
// Do your logic here
// Show the modal
}
}
Then add a method to your page, or page base like this...
public void ShowModal(string someParameter)
{
MyMaster masterPage = this.Master as MyMaster;
masterPage.ShowModal(someParameter);
}
I recommend using a base class for your pages so that you don't have to replicate the above method.
Add a method to your Master page. For example:
public void ShowMpSignup4free()
{
mpSignup4free.Show();
}
Then call this method from the code behind page like this:
protected void lbSignin_Click(object sender, EventArgs e)
{
MasterPages_WebMasterPage wm = (MasterPages_WebMasterPage)(this.Master);
wm.ShowMpSignup4free();
}
Here mpSignup4free is ID of ModelPopupExtender and MasterPages_WebMasterPage is name of master page (WebMasterPage is name of master page placed in folder MasterPages. That is why the complete name of master page is MasterPages_WebMasterPage).
and lbSignin is Link button on the page whose master page is WebMasterPage to whose click event will show the model popup.
For avoiding post back place the lbSignin link button in UpdatePanel...