ListView control

  • Thread starter Thread starter Brian Gaze
  • Start date Start date
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Brian Gaze

I have created a ListView control and have bound this to a datasource.
Within the ItemTemplate of the ListView I have added another ListViewControl
which is databound in the code behind. The idea is that when clicking on the
"Show details" button the ListView for the appropriate row binds in the
codebehind and displays the detail data for the selected row. I did
something similar with a gridview control previously, but want to be able to
fully control the HTML produced now so don't want to go down that route.

The problem I am having is that the master ListView renders with the correct
data, but the embedded details ListView does not display at all. If I pull
the details ListView out of the master ListView and create seperately it
does render correctly. Is the problem being caused because the master
ListView is rendering before the details ListView is generated? Any help
appreciated.

Regards

Brian


Here's the code......

I'm trying to bind the details ListView in the SelectedIndexChanged event
of the master ListView, with something like this in the codebehind:

ListView tmp = new ListView();
tmp = (ListView)this.ListView1.Items[rowcount].FindControl("lvDetails");
tmp.DataSourceID = "ods1";
tmp.DataBind();


The declarative code is...

<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID="LinkButton1" runat="server"
CausesValidation="False" CommandName="Select"
Text="Show details"
OnClick="LinkButton1_Click"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server"
CausesValidation="False" CommandName="Cancel"
Text="Hide details"></asp:LinkButton>
<asp:Label ID="Label10" runat="server" Text='<%#
Eval("[Field1]") + "kmh" %>'></asp:Label>
</td>
<td>
<asp:Label ID="Label9" runat="server" Text='<%#
Eval("Field2") + "mB"%>'></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:ListView ID="lvDetails" runat="server"
EnableViewState="false">
<LayoutTemplate>
<ul>
<asp:PlaceHolder ID="itemPlaceholder"
runat="server"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<%# Eval("[Wind speed]")%>
<%# Eval("[Temperature]")%>
</li>
</ItemTemplate>
</asp:ListView>
</td>

</tr>
</ItemTemplate>
 
The line
ListView tmp = new ListView();
is not needed. You are creating an instance of ListView and the next line is
going to override the reference to this instance with the one already
defined in the template. But that is not the reason for your problem.

In declarative databinding you need to run Select on the datasource to get
the data programmatically. Without this, tmp.Databind() won't help since it
will bind to an empty datasource. Replace
tmp.DataBind();
with
ods1.Select()
and see if it works.


--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


Brian Gaze said:
I have created a ListView control and have bound this to a datasource.
Within the ItemTemplate of the ListView I have added another
ListViewControl which is databound in the code behind. The idea is that
when clicking on the "Show details" button the ListView for the appropriate
row binds in the codebehind and displays the detail data for the selected
row. I did something similar with a gridview control previously, but want
to be able to fully control the HTML produced now so don't want to go down
that route.

The problem I am having is that the master ListView renders with the
correct data, but the embedded details ListView does not display at all.
If I pull the details ListView out of the master ListView and create
seperately it does render correctly. Is the problem being caused because
the master ListView is rendering before the details ListView is generated?
Any help appreciated.

Regards

Brian


Here's the code......

I'm trying to bind the details ListView in the SelectedIndexChanged event
of the master ListView, with something like this in the codebehind:

ListView tmp = new ListView();
tmp = (ListView)this.ListView1.Items[rowcount].FindControl("lvDetails");
tmp.DataSourceID = "ods1";
tmp.DataBind();


The declarative code is...

<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID="LinkButton1" runat="server"
CausesValidation="False" CommandName="Select"
Text="Show details"
OnClick="LinkButton1_Click"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server"
CausesValidation="False" CommandName="Cancel"
Text="Hide details"></asp:LinkButton>
<asp:Label ID="Label10" runat="server" Text='<%#
Eval("[Field1]") + "kmh" %>'></asp:Label>
</td>
<td>
<asp:Label ID="Label9" runat="server" Text='<%#
Eval("Field2") + "mB"%>'></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:ListView ID="lvDetails" runat="server"
EnableViewState="false">
<LayoutTemplate>
<ul>
<asp:PlaceHolder ID="itemPlaceholder"
runat="server"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<%# Eval("[Wind speed]")%>
<%# Eval("[Temperature]")%>
</li>
</ItemTemplate>
</asp:ListView>
</td>

</tr>
</ItemTemplate>
Click to expand...
 
Thanks - that resolves the problem I was having with sub ListView not
rendering, but introduces another issue. A sub ListView (with the same data
in each case) is rendered for each item returned in the master ListView.
What I'm trying to do is only render a sub ListView for the item currently
selected in the master ListView.

Any ideas?

Brian


Eliyahu Goldin said:
The line
ListView tmp = new ListView();
is not needed. You are creating an instance of ListView and the next line
is going to override the reference to this instance with the one already
defined in the template. But that is not the reason for your problem.

In declarative databinding you need to run Select on the datasource to get
the data programmatically. Without this, tmp.Databind() won't help since
it will bind to an empty datasource. Replace
tmp.DataBind();
with
ods1.Select()
and see if it works.


--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


Brian Gaze said:
I have created a ListView control and have bound this to a datasource.
Within the ItemTemplate of the ListView I have added another
ListViewControl which is databound in the code behind. The idea is that
when clicking on the "Show details" button the ListView for the
appropriate row binds in the codebehind and displays the detail data for
the selected row. I did something similar with a gridview control
previously, but want to be able to fully control the HTML produced now so
don't want to go down that route.

The problem I am having is that the master ListView renders with the
correct data, but the embedded details ListView does not display at all.
If I pull the details ListView out of the master ListView and create
seperately it does render correctly. Is the problem being caused because
the master ListView is rendering before the details ListView is
generated? Any help appreciated.

Regards

Brian


Here's the code......

I'm trying to bind the details ListView in the SelectedIndexChanged
event of the master ListView, with something like this in the codebehind:

ListView tmp = new ListView();
tmp = (ListView)this.ListView1.Items[rowcount].FindControl("lvDetails");
tmp.DataSourceID = "ods1";
tmp.DataBind();


The declarative code is...

<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID="LinkButton1" runat="server"
CausesValidation="False" CommandName="Select"
Text="Show details"
OnClick="LinkButton1_Click"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server"
CausesValidation="False" CommandName="Cancel"
Text="Hide details"></asp:LinkButton>
<asp:Label ID="Label10" runat="server" Text='<%#
Eval("[Field1]") + "kmh" %>'></asp:Label>
</td>
<td>
<asp:Label ID="Label9" runat="server" Text='<%#
Eval("Field2") + "mB"%>'></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:ListView ID="lvDetails" runat="server"
EnableViewState="false">
<LayoutTemplate>
<ul>
<asp:PlaceHolder ID="itemPlaceholder"
runat="server"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<%# Eval("[Wind speed]")%>
<%# Eval("[Temperature]")%>
</li>
</ItemTemplate>
</asp:ListView>
</td>

</tr>
</ItemTemplate>
Click to expand...
Click to expand...
 
Why is it rendered for each item? Don't you handle the SelectedIndexChanged
event? In any case, since you are already in code-behind, you can code any
logic as when to populate the sub listview.

--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


Brian Gaze said:
Thanks - that resolves the problem I was having with sub ListView not
rendering, but introduces another issue. A sub ListView (with the same
data in each case) is rendered for each item returned in the master
ListView. What I'm trying to do is only render a sub ListView for the item
currently selected in the master ListView.

Any ideas?

Brian


Eliyahu Goldin said:
The line
ListView tmp = new ListView();
is not needed. You are creating an instance of ListView and the next line
is going to override the reference to this instance with the one already
defined in the template. But that is not the reason for your problem.

In declarative databinding you need to run Select on the datasource to
get the data programmatically. Without this, tmp.Databind() won't help
since it will bind to an empty datasource. Replace
tmp.DataBind();
with
ods1.Select()
and see if it works.


--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


Brian Gaze said:
I have created a ListView control and have bound this to a datasource.
Within the ItemTemplate of the ListView I have added another
ListViewControl which is databound in the code behind. The idea is that
when clicking on the "Show details" button the ListView for the
appropriate row binds in the codebehind and displays the detail data for
the selected row. I did something similar with a gridview control
previously, but want to be able to fully control the HTML produced now so
don't want to go down that route.

The problem I am having is that the master ListView renders with the
correct data, but the embedded details ListView does not display at all.
If I pull the details ListView out of the master ListView and create
seperately it does render correctly. Is the problem being caused because
the master ListView is rendering before the details ListView is
generated? Any help appreciated.

Regards

Brian


Here's the code......

I'm trying to bind the details ListView in the SelectedIndexChanged
event of the master ListView, with something like this in the
codebehind:

ListView tmp = new ListView();
tmp =
(ListView)this.ListView1.Items[rowcount].FindControl("lvDetails");
tmp.DataSourceID = "ods1";
tmp.DataBind();


The declarative code is...

<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID="LinkButton1" runat="server"
CausesValidation="False" CommandName="Select"
Text="Show details"
OnClick="LinkButton1_Click"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server"
CausesValidation="False" CommandName="Cancel"
Text="Hide details"></asp:LinkButton>
<asp:Label ID="Label10" runat="server" Text='<%#
Eval("[Field1]") + "kmh" %>'></asp:Label>
</td>
<td>
<asp:Label ID="Label9" runat="server" Text='<%#
Eval("Field2") + "mB"%>'></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:ListView ID="lvDetails" runat="server"
EnableViewState="false">
<LayoutTemplate>
<ul>
<asp:PlaceHolder ID="itemPlaceholder"
runat="server"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<%# Eval("[Wind speed]")%>
<%# Eval("[Temperature]")%>
</li>
</ItemTemplate>
</asp:ListView>
</td>

</tr>
</ItemTemplate>
Click to expand...
Click to expand...
Click to expand...
 
Thanks. The easiest solution for me was to add the sub ListView
declaratively in the SelectedItemtemplate.

Brian



Eliyahu Goldin said:
Why is it rendered for each item? Don't you handle the
SelectedIndexChanged event? In any case, since you are already in
code-behind, you can code any logic as when to populate the sub listview.

--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


Brian Gaze said:
Thanks - that resolves the problem I was having with sub ListView not
rendering, but introduces another issue. A sub ListView (with the same
data in each case) is rendered for each item returned in the master
ListView. What I'm trying to do is only render a sub ListView for the
item currently selected in the master ListView.

Any ideas?

Brian


Eliyahu Goldin said:
The line
ListView tmp = new ListView();
is not needed. You are creating an instance of ListView and the next
line is going to override the reference to this instance with the one
already defined in the template. But that is not the reason for your
problem.

In declarative databinding you need to run Select on the datasource to
get the data programmatically. Without this, tmp.Databind() won't help
since it will bind to an empty datasource. Replace
tmp.DataBind();
with
ods1.Select()
and see if it works.


--
Eliyahu Goldin,
Software Developer
Microsoft MVP [ASP.NET]
http://msmvps.com/blogs/egoldin
http://usableasp.net


I have created a ListView control and have bound this to a datasource.
Within the ItemTemplate of the ListView I have added another
ListViewControl which is databound in the code behind. The idea is that
when clicking on the "Show details" button the ListView for the
appropriate row binds in the codebehind and displays the detail data for
the selected row. I did something similar with a gridview control
previously, but want to be able to fully control the HTML produced now
so don't want to go down that route.

The problem I am having is that the master ListView renders with the
correct data, but the embedded details ListView does not display at
all. If I pull the details ListView out of the master ListView and
create seperately it does render correctly. Is the problem being caused
because the master ListView is rendering before the details ListView is
generated? Any help appreciated.

Regards

Brian


Here's the code......

I'm trying to bind the details ListView in the SelectedIndexChanged
event of the master ListView, with something like this in the
codebehind:

ListView tmp = new ListView();
tmp =
(ListView)this.ListView1.Items[rowcount].FindControl("lvDetails");
tmp.DataSourceID = "ods1";
tmp.DataBind();


The declarative code is...

<ItemTemplate>
<tr>
<td>
<asp:LinkButton ID="LinkButton1" runat="server"
CausesValidation="False" CommandName="Select"
Text="Show details"
OnClick="LinkButton1_Click"></asp:LinkButton>
<asp:LinkButton ID="LinkButton2" runat="server"
CausesValidation="False" CommandName="Cancel"
Text="Hide details"></asp:LinkButton>
<asp:Label ID="Label10" runat="server" Text='<%#
Eval("[Field1]") + "kmh" %>'></asp:Label>
</td>
<td>
<asp:Label ID="Label9" runat="server" Text='<%#
Eval("Field2") + "mB"%>'></asp:Label>
</td>
</tr>
<tr>
<td colspan="2">
<asp:ListView ID="lvDetails" runat="server"
EnableViewState="false">
<LayoutTemplate>
<ul>
<asp:PlaceHolder ID="itemPlaceholder"
runat="server"></asp:PlaceHolder>
</ul>
</LayoutTemplate>
<ItemTemplate>
<li>
<%# Eval("[Wind speed]")%>
<%# Eval("[Temperature]")%>
</li>
</ItemTemplate>
</asp:ListView>
</td>

</tr>
</ItemTemplate>
Click to expand...
Click to expand...
Click to expand...
 
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