I have a ListView in an ASP.NET web application. When a user clicks the edit button, I want textfields to pop up that are dependent on certain values of the item. However, I can't seem to find any controls inside of my ListView1_ItemEditing() function.
I have read the Microsoft documentation and various help threads on the internet, but their suggestions do not appear to work for me. This is generally what I see:
ListViewItem item = ProductsListView.Items[e.NewEditIndex];
Label dateLabel = (Label)item.FindControl("DiscontinuedDateLabel");
For the sake of simplicity I just want to be able to select a label in ListView1_ItemEditing(). This is the code in ListView1_ItemEditing():
protected void ListView1_ItemEditing(Object sender, ListViewEditEventArgs e)
{
DataBind(); //not sure if this does anything
ListViewItem item = ListView1.Items[e.NewEditIndex];
Label debugLabel = (Label)item.FindControl("label_editing");
debugLabel.Text = "Works";
}
Here is the ASP
<EditItemTemplate>
<asp:Label ID="label_editing" runat="server" Text="hello world"></asp:Label>
</EditItemTemplate>
When debugging, item and debugLabel are both NULL.
UPDATE: I resolved this issue by moving my logic to ItemDataBound and then checking if my tr (containing textboxes) was in that particular data item. Code below:
protected void ListView1_ItemDataBound(object sender, ListViewItemEventArgs e)
{
if (e.Item.ItemType == ListViewItemType.DataItem)
{
Control tr_verizon = e.Item.FindControl("tr_verizonEdit");
Control tr_att = e.Item.FindControl("tr_attEdit");
if (tr_verizon != null)
{
//Control tb_meid = e.Item.FindControl("TextBox_Meid");
Label lbl_carrierId = (Label)e.Item.FindControl("lbl_carrierId");
if (lbl_carrierId == null)
{
Message.Text = "lbl_carrierId is null!";
}
else if (lbl_carrierId.Text.Equals(""))
{
Message.Text = "lbl_carrierId is empty!";
}
else
{
string recordId = lbl_carrierId.Text;
if (tr_verizon != null && tr_att != null)
{
if (lbl_carrierId.Text.Equals("1"))
{
tr_verizon.Visible = false;
tr_att.Visible = true;
}
else
{
tr_verizon.Visible = true;
tr_att.Visible = false;
}
}
}
}
}
}
The ItemEditing event is raised when an item's Edit button is clicked, but before the ListView item is put in edit mode. Therefore controls in EditItemTemplate are not available at this time.
More Info and example
You should do the DataBind() first, like this:
ListView1.EditIndex = e.NewEditIndex;
ListView1_BindData(); // a function that get the DataSource and then ListView1.DataBind()
// Now find the control as you did before
Have you tried casting the sender object instead of trying to access your ListViewItem by index?
protected void ListView1_ItemEditing(Object sender, ListViewEditEventArgs e)
{
var item = sender as ListViewItem;
var debugLabel = item.FindControl("label_editing") as Label;
debugLabel.Text = "Works";
}
Related
I have a project that using dropdownlist for choices.When check checkbox1 dropdown automatically bind data from database using table1 and when I check checkbox2 dropdown automatically binding data from database using table2.I do not want to use get data by using any button .How can I do that .Please help me.
here is code by using button:
public void LokasyonDoldur()
{
birimBUS = new BirimBUSV1();
List<BirimVO> birimVO = new List<BirimVO>();
DrpChcs.Items.Clear();
List<ListItem> items = new List<ListItem>();
birimVO = birimBUS.LokasyonlariGetir();
foreach (var item in birimVO)
{
items.Add(new ListItem(item.BirimAdi, item.ID.ToString()));
}
DrpChcs.Items.AddRange(items.ToArray());
}
public void BirimleriDoldur()
{
PoliklinikBUS poliklinikBUS = new PoliklinikBUS();
List<PoliklinikVO> poliklinikVO = new List<PoliklinikVO>();
DrpChcs.Items.Clear();
List<ListItem> items = new List<ListItem>();
poliklinikVO = poliklinikBUS.Poliklinikler();
foreach (var item in poliklinikVO)
{
items.Add(new ListItem(item.PoliklinikAdi, item.ID.ToString()));
}
DrpChcs.Items.AddRange(items.ToArray());
}
protected void BtnLokasyon_Click(object sender, EventArgs e)
{
if (ChckLctn.Checked == true && ChckBrm.Checked==false)
{
LokasyonDoldur();
}
else if (ChckLctn.Checked == false && ChckBrm.Checked == true)
{
BirimleriDoldur();
}
else
{
}
Button1.Visible = true;
BtnLokasyon.Visible = false;
}
protected void DrpChcs_SelectedIndexChanged(object sender, EventArgs e)
{
}
protected void Button1_Click(object sender, EventArgs e)
{
KirilimId = Int32.Parse(DrpChcs.SelectedValue);
BPolikilinikID= KirilimId;
}
but I do not want to use this one.
ohh its another language. its hard to read. but what you basicly have to do is check which checkbox is checked in the page load and then load the dropdown based on what is loaded.
something like this. (I have typed it from my head so its not like copy-paste but you get the idea)
page_load
{
if(checkbox1.checked)
{
dropdown.dataitems = items1;
dropdown.databind();
return;
}
if(checkbox2.checked)
{
dropdown.dataitems = items2;
dropdown.databind();
return;
}
}
YOu can call the Button1_click event from the Dropdown list selected index changed event like this
Button1_Click(Button1,new EventArgs());
and in this you can hide that button from the page and in code behind you are calling the same function
OR
You can refactor the code in a seperate function from the button click event and call that function in the selected index changed event.
Please let me knwo if I misunderstood your question
Thanks
I have a repeater with one delete button and bind it to a list like this:
page_load()
{
list<person> myList = new list<person>()
myList.add(new person(Id="1",Name="n1"));
if(!isPostBack)
{
myList.add(new person(Id="2",Name="n2"));
myRepeater.DataSource = myList;
myrepeater.DataBind();
}
myRepeater.ItemCommand += myHandler;
}
void AdverticRp_ItemCommand(object source, RepeaterCommandEventArgs e)
{
if(e.CommandName == "delete")
{
FileUploader fu = myrepeater.FindControl("fu") as FileUploadr;
// do somthing ** * but contorls is null refrence ***
}
}
the repeater bind successfully and delete button raised correctly but i want get contorls in myrepeater but they are null refrence. i know why. because repeater not binded in postback. what should i do? must save state of repeater in veiwsate?
I think im wrong in binding. but what is the correct one?
I appreciate for all help.
If you disable viewstate, you won't see them unless you databind on every page load. You are getting your values from viewstate
Check link.
Find the control from the repeater's Items, not on the repeater itseld. Try this:
void AdverticRp_ItemCommand(object source, RepeaterCommandEventArgs e)
{
if(e.CommandName == "delete")
{
RepeaterItem item = e.Item;
if (item.ItemType == ListItemType.Item || item.ItemType == ListItemType.AlternatingItem)
{
FileUploader fu = item.FindControl("fu") as FileUploader;
// do somthing here
}
}
}
I am using a wizard. and in step two the user can add information about a location that will be stored. He can add as many locations as he likes.
In step three I want to enter more information about the specific location.
To select which location to use I have ASP:dropdownlist that I populate when user enters stuff.
I want to change index but it just does not work It never goes into the function when I tried debugging. I am using a label to debug.
When I change the selected item the page reloads and the first item in the dropdown list is always selected even though I selected something else. I do not understand why that happens
here is what I have
ASPX File
Select location to enter data for:
<asp:DropDownList ID="s3_location_list" runat="server" AutoPostBack="true" OnSelectedIndexChanged="stepThree_location_list_SelectedIndexChanged">
</asp:DropDownList>
Current location index:
<asp:Label ID="Label3" runat="server" Text="Label"></asp:Label>
CS files
/*This is where I add data to the drop down list
protected void stepTwo_addLocationData(object Sender, System.EventArgs e)
{
//initialize a temporary string array to get all the data from the form
//Console.Write("AAAAA"+ Context.Items["IsRefreshed"]);
Boolean refreshed = (Boolean)Context.Items["IsRefreshed"];
if (!refreshed)
{
//if user is adding a new entry to the location table
LocationData new_location = new LocationData();
//add stuff to locationData
if (stepTwo_locationTableIndex == -1)
{
//add the new_location element into the location_data array
location_data.Add(new_location);
//redraw the table
DataRow dr = dt.NewRow();
dr["Location"] = new_location.City;
//dr["Name"] = loc;
dt.Rows.Add(dr);
}
else
{
location_data[stepTwo_locationTableIndex] = new_location;
dt.Rows[stepTwo_locationTableIndex]["Location"] = City.Text;
}
GridView1.DataSource = dt.DefaultView;
GridView1.DataBind();
///CreateTable();
stepFive_setLocationListOptions();
stepThree_setLocationListOptions();
stepTwo_resetForm();
}
/*this is the page load on step 3
protected void stepThree_load()
{
if (!IsPostBack && Session["s_s3_locationDropdownIndex"] == null)
{
stepThree_locationDropdownIndex = s3_location_list.SelectedIndex;
Session["s_s3_locationDropdownIndex"] = stepThree_locationDropdownIndex;
}
else
{
stepThree_locationDropdownIndex = (int) Session["s_s3_locationDropdownIndex"];
}
s3_location_list.SelectedIndex = stepThree_locationDropdownIndex;
Label3.Text = "" + s3_location_list.SelectedIndex;
}
/*this is my where I populate the list
protected void stepThree_setLocationListOptions()
{
s3_location_list.Items.Clear();
int i = 0;
foreach (LocationData item in location_data)
{
s3_location_list.Items.Add(new ListItem(item.City, "" + i));
}
s3_location_list.DataBind();
}
/* this is the function thats callled when selected index is changed.
protected void stepThree_location_list_SelectedIndexChanged(object sender, EventArgs e)
{
Label3.Text = "Hello";
}
I think the problem is the order of execution. You should only initialize a DropDownList once, otherwise it will overwrite your SelectedIndex. For example, use the OnInit event:
<asp:DropDownList ID="s3_location_list"
runat="server"
OnInit="s3_location_list_Init"/>
And write the event method like this:
protected void s3_location_list_Init(object sender, EventArgs e)
if (!IsPostBack) {
foreach (LocationData item in location_data)
{
s3_location_list.Items.Add(new ListItem(item.City, "" + i));
}
s3_location_list.DataBind();
}
}
This must be something that a lot of people have done. Basically, it's a custom GridView (i.e. inherited control) with the ability to update all rows at once. I've tried putting the "update all" button in various places (footer, pager, outside the grid), but it looks neatest (to me) when the button is in an extra row as the last row of the GridView.
NB: The pager row is not a suitable place for this button because this custom control could be used in a situation where paging is false. Similarly, the normal footer may be required for some other purpose (e.g. totals).
Here's my code for putting the button in the correct place (with apologies for the terse variables etc.):
protected override void OnPreRender(EventArgs e)
{
base.OnPreRender(e);
//Add an extra row to the table...
if (_updateAllEnabled)
{
GridViewRow r = base.CreateRow(-1, -1, DataControlRowType.Footer, DataControlRowState.Normal);
Button btn = new Button();
TableCell c = new TableCell();
btn.ID = "UpdateAllButton"; // tried with and without this line
btn.Text = "Update All";
btn.Click += new EventHandler(UpdateAll);
r.Cells.Add(c);
c.Controls.Add(btn);
Table t = this.Controls[0] as Table;
c.ColumnSpan = this.Columns.Count;
t.Rows.Add(r);
}
}
This gives the appearance that I want, but the click event (UpdateAll) does not fire.
I assume that the stuff is being added too late in the life cycle (PreRender), but where else can I do this to ensure that the row is at the end of the GridView? I also thought that there might be trouble identifying the button, so I tried setting the ID. In any case, the ID in the generated HTML looks OK (consistent with "working" buttons in the pager row.
Is there a way for me to achieve this or am I attempting the impossible?
The best place to create your footer-controls is RowCreated since that's early enough in the lifecycle and also ensures that their recreated on every postback:
Footer approach:
protected void Grid_RowCreated(Object sender, GridViewRowEventArgs e) {
if(e.Row.RowType == DataControlRowType.Footer) {
Button btn = new Button();
TableCell c = new TableCell();
btn.ID = "UpdateAllButton";
btn.Text = "Update All";
btn.Click += new EventHandler(UpdateAll);
var firstCell=e.Row.Cells[0];
firstCell.ColumnSpan =e.Row.Cells.Count;
firstCell.Controls.Add(btn);
while(e.Row.Cells.Count > 1)e.Row.Cells.RemoveAt(e.Row.Cells.Count-1);
}
}
Of course you have to set ShowFooter to true:
<asp:GridView ID="GridView1"
ShowFooter="true"
OnRowCreated="Grid_RowCreated"
runat="server"
</asp:GridView>
Pager approach:
In my opinion this is the purpose of the FooterRow. But if you really want to ensure that your Button is in the very last row of a GridView(even below Pager as commented), i would try my next approach.
Here I'm using the pager for your costom control(s) by adding another TableRow to the PagerTable which inherits from Table.
protected void Grid_RowCreated(Object sender, GridViewRowEventArgs e) {
switch(e.Row.RowType){
case DataControlRowType.Pager:
Button btnUpdate = new Button();
btnUpdate.ID = "UpdateButton";
btnUpdate.Text = "Update";
btnUpdate.Click += new EventHandler(UpdateAll);
var tblPager = (Table)e.Row.Cells[ 0 ].Controls[ 0 ];
var row = new TableRow();
var cell = new TableCell();
cell.ColumnSpan = tblPager.Rows[ 0 ].Cells.Count;
cell.Controls.Add(btnUpdate);
row.Cells.Add(cell);
tblPager.Rows.Add(row);
break;
}
}
To ensure that the pager is visible even if only one page is shown(note that the real pager is invisible if PageSize==1):
protected void Grid_PreRender(object sender, EventArgs e){
GridView gv = (GridView)sender;
GridViewRow gvr = (GridViewRow)gv.BottomPagerRow;
if(gvr != null) {
gvr.Visible = true;
var tblPager = (Table)gvr.Cells[ 0 ].Controls[ 0 ];
//hide real pager if unnecessary
tblPager.Rows[ 0 ].Visible = GridView1.PageCount > 1;
}
}
Of course now you have to set AllowPaging=true:
<asp:GridView ID="GridView1"
AllowPaging="true"
PagerSettings-Mode="NumericFirstLast"
OnRowCreated="Grid_RowCreated"
OnPreRender="Grid_PreRender"
OnPageIndexChanging="Grid_PageChanging"
runat="server">
</asp:GridView>
Final approach(working for a custom GridView and all PagerPositions):
public PagerPosition OriginalPagerPosition{
get { return (PagerPosition)ViewState[ "OriginalPagerPosition" ]; }
set { ViewState[ "OriginalPagerPosition" ] = value; }
}
protected void Page_Load(object sender, EventArgs e){
if(!IsPostBack) OriginalPagerPosition = GridView1.PagerSettings.Position;
GridView1.PagerSettings.Position = PagerPosition.TopAndBottom;
GridView1.AllowPaging = true;
// databinding stuff ...
}
Keep the RowCreated the same as above in Pager approach.
Visibility of top/bottom pagers will be controlled in PreRender according to the OriginalPagerPosition property. Both pagers are created even with PagerPosition=TOP, the bottom pager is required for your additional control(s):
protected void Grid_PreRender(object sender, EventArgs e)
{
GridView gv = (GridView)sender;
GridViewRow tpr = (GridViewRow)gv.TopPagerRow;
GridViewRow bpr = (GridViewRow)gv.BottomPagerRow;
tpr.Visible = gv.PageCount > 1 && (OriginalPagerPosition == PagerPosition.Top || OriginalPagerPosition == PagerPosition.TopAndBottom);
bpr.Visible = true;
var tblBottomPager = (Table)bpr.Cells[ 0 ].Controls[ 0 ];
tblBottomPager.Rows[ 0 ].Visible = gv.PageCount > 1 && (OriginalPagerPosition == PagerPosition.Bottom || OriginalPagerPosition == PagerPosition.TopAndBottom);
var tblTopPager = (Table)tpr.Cells[ 0 ].Controls[ 0 ];
tblTopPager.Rows[1].Visible = false;
}
Note: if you are extending the GridView control, you have to replace all occurences of GridView1(my test-grid) with this.
It would be easy to add an extra row into the grid. But the difficulty in your requirement is that the GridView's RowCollection should not contain this row since that would be error-prone. It should also be the very last row even if paging is enabled. This is (afaik) not possible.
Hence i've chosen to extend the pager with this functionality.
I'll add this as separate answer since my other is already too detailed and describes two different ways(footer,pager) to add controls to a GridView without extending it.
This approach extends a GridView as in your own requirement and is similar to my other pager-approach. But it's cleaner and only adds the additional row to the BottomPager. It woks also for every setting(AllowPaging=false,Pager-Position: Top,Bottom,BottomTop):
[DefaultProperty("EnableUpdateAll")]
[ToolboxData("<{0}:UpdateGridView runat=server></{0}:UpdateGridView>")]
public class UpdateGridView : GridView
{
[Bindable(true)]
[Category("Appearance")]
[DefaultValue("true")]
[Localizable(true)]
public bool EnableUpdateAll
{
get
{
Object val = ViewState["EnableUpdateAll"];
return ((val == null) ? true : (bool)val);
}
set
{
ViewState["EnableUpdateAll"] = value;
}
}
private bool OriginalAllowPaging
{
get
{
Object val = ViewState["OriginalAllowPaging"];
return (bool)val;
}
set
{
ViewState["OriginalAllowPaging"] = value;
}
}
private PagerPosition OriginalPagerPosition
{
get
{
Object val = ViewState["OriginalPagerPosition"];
return (PagerPosition)val;
}
set
{
ViewState["OriginalPagerPosition"] = value;
}
}
protected override void OnInit(System.EventArgs e)
{
if (ViewState["OriginalPagerPosition"] == null)
OriginalPagerPosition = base.PagerSettings.Position;
if(OriginalPagerPosition != PagerPosition.Bottom)
PagerSettings.Position=PagerPosition.TopAndBottom;
if (ViewState["OriginalAllowPaging"] == null)
OriginalAllowPaging = base.AllowPaging;
base.AllowPaging = true;
}
protected override void OnRowCreated(GridViewRowEventArgs e)
{
switch (e.Row.RowType)
{
case DataControlRowType.Pager:
//check if we are in BottomPager
if (this.Rows.Count != 0 && this.EnableUpdateAll)
{
Button btnUpdate = new Button();
btnUpdate.ID = "BtnUpdate";
btnUpdate.Text = "Update";
btnUpdate.Click += new EventHandler(UpdateAll);
var tblPager = (Table)e.Row.Cells[0].Controls[0];
var row = new TableRow();
var cell = new TableCell();
cell.ColumnSpan = tblPager.Rows[0].Cells.Count;
cell.Controls.Add(btnUpdate);
row.Cells.Add(cell);
tblPager.Rows.Add(row);
}
break;
}
}
protected override void OnPreRender(EventArgs e)
{
bool bottomPagerVisible =
OriginalAllowPaging &&
PageCount > 1 &&
(OriginalPagerPosition == PagerPosition.Bottom || OriginalPagerPosition == PagerPosition.TopAndBottom);
BottomPagerRow.Visible = bottomPagerVisible || EnableUpdateAll;
var tblBottomPager = (Table)BottomPagerRow.Cells[0].Controls[0];
tblBottomPager.Rows[0].Visible = bottomPagerVisible;
}
private void UpdateAll(Object sender, EventArgs e)
{
// do something...
}
}
So I have a listbox on my page and some textfields. Through the textfields I can add an item to my listbox (click the button, it adds it to a private List<string> which is then set as a ViewState and the list is databound again).
My listbox is also in an updatepanel which gets triggered on the button's Click event.
Problem: My Viewstate remains null on a postback so it gets reset each time.
Some code:
private List<IngredientData> _ingredientsList;
protected void Page_Load(object sender, EventArgs e)
{
// prepare ingredient lists
_ingredientsList = new List<IngredientData>();
if (Page.IsPostBack)
{
if (ViewState["IngredientsList"] != null)
{
_ingredientsList = (List<IngredientData>) ViewState["IngredientsList"];
}
}
lstIngredients.DataSource = _ingredientsList;
lstIngredients.DataTextField = "Text";
lstIngredients.DataValueField = "Name";
lstIngredients.DataBind();
}
protected void btnAddIngredient_Click(object sender, EventArgs e)
{
_ingredientsList.Add(new IngredientData { Name = txtIngredientName.Text, Quantity = txtUnitQuantity.Text, Unit = lstUnits.SelectedValue });
ViewState["IngredienstList"] = _ingredientsList;
lstIngredients.DataSource = _ingredientsList;
lstIngredients.DataBind();
}
Any idea how I can fix this? Am I doing something wrong?
btnAddIngredient_Click is adding to "IngredienstList" not "IngredientsList" (note the spelling).
You can avoid this kind of typo by using a constant:
private const string IngredientsListViewStateKey = "IngredientsList";
then referring to it like this:
ViewState[IngredientsListViewStateKey] = _ingredientsList;