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[CLOSED] combobox value disappear after button click

  1. #1
    Dec 19, 2014, 4:35 AM

    [CLOSED] combobox value disappear after button click

    Hi
    I have a combobox and a button ,and the button set with AutoPostback="true",after click on button combobox value disappear,please run the test case,also I found EmptyValue property not present in combobox.

    Sample Aspx
    <html>

<body>
    <form id="Form1" runat="server">
       <ext:ResourceManager ID="ResourceManager1" runat="server" DisableViewState="false" />
        <ext:ComboBox runat="server" ID="cmpDepartment" Editable="true" DisplayField="DepartmentName" ValueField="DepartmentID" TypeAhead="true"
            EmptyText="All">
            <Triggers>
                <ext:FieldTrigger Icon="Clear" HideTrigger="true">
                </ext:FieldTrigger>

            </Triggers>
            <Listeners>
                <Select Handler="this.getTrigger(0).show();" />
                <BeforeQuery Handler="this.getTrigger(0)[this.getRawValue().toString().length == 0 ? 'hide' : 'show']();" />
                <TriggerClick Handler="if (index == 0) {
                                           this.clearValue();
                                           this.getTrigger(0).hide();
                                       }" />
            </Listeners>
            <Store>
                <ext:Store
                    runat="server"
                    ID="DepartmentStore">

                    <Model>
                        <ext:Model ID="Model1" runat="server" IDProperty="DepartmentID">
                            <Fields>
                                <ext:ModelField Name="DepartmentID" Type="Int" />
                                <ext:ModelField Name="DepartmentName" Type="String" />
                            </Fields>
                        </ext:Model>
                    </Model>
                </ext:Store>
            </Store>

        </ext:ComboBox>
        <ext:DisplayField runat="server" ID="df" PaddingSpec="0 0 0 25" Html="&nbsp;"></ext:DisplayField>
        <ext:Button runat="server" ID="btn" OnClick="btn_Click" Text="Click" AutoPostBack="true"></ext:Button>
    </form>
</body>
</html>
    Sample Code

    public partial class delayed_event : System.Web.UI.Page
    {
        protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                LoadCombo();
            }
        }

        private void LoadCombo()
        {
            Department d ;
            List<Department> _d = new List<Department>();
            for (int i = 0; i <= 4; i++)
            {
                d = new Department();
                d.DepartmentID = i;
                d.DepartmentName = "Department - " + i.ToString();
                _d.Add(d);
            }

            DepartmentStore.DataSource = _d;
            DepartmentStore.DataBind();
        }

        protected void btn_Click(object sender, EventArgs e)
        {

        }


    }

    public class Department
    {
        public int DepartmentID { get; set; }
        public string DepartmentName { get; set; }
    }
    Last edited by Daniil; Feb 25, 2015 at 9:13 AM. Reason: [CLOSED]
  2. #2
    Dec 19, 2014, 5:56 AM
    Hi @matrixwebtech,

    You should replace
    if (!IsPostBack)
    with
    if (!X.IsAjaxRequest)
    Otherwise, the ComboBox's Store is just not binding to the data on PostBack.
  3. #3
    Dec 19, 2014, 6:08 AM
    Hi ,Daniil
    Change according your suggestion ,now its working.but there are one problem.

    1.I select a value from combobox,and the trigger button visible as expected.
    2.click on button ,trigger button disappear.
    how to fix this?
  4. #4
    Dec 19, 2014, 6:12 AM
    I would try FireSelectOnLoad="true" for the ComboBox.
  5. #5
    Dec 19, 2014, 6:20 AM
    thank you very much for help.there are many small small tricks in EXT.Net .please close this thread.
  6. #6
    Feb 12, 2015, 2:28 PM
    I add after data bind in LoadCombo() function bellow code to add a All Option to the combo

    DepartmentStore.DataSource = _d;
            DepartmentStore.DataBind();
         this.cmpDepartment.SelectedItems.Clear();
            this.cmpDepartment.Items.Insert(0, new Ext.Net.ListItem { Text = "All", Value = "0" });
            this.cmpDepartment.SelectedItems.Add(new Ext.Net.ListItem { Index = 0 });
    All option added.but when I click on button selected item always lost and always All get selected.without adding All button click code works fine.
  7. #7
    Feb 13, 2015, 1:13 PM
    any thought ?
  8. #8
    Feb 13, 2015, 6:59 PM
    Mm, I don't quite understand the issue.

    Please provide a full test case. Then we could investigate.
  9. #9
    Feb 14, 2015, 2:07 PM
    Please try bellow code

    <ext:ComboBox runat="server" ID="cmdtest" Editable="true" DisplayField="DepartmentName" ValueField="DepartmentID" TypeAhead="true"
                        EmptyText="All">
                        <Triggers>
                            <ext:FieldTrigger Icon="Clear" HideTrigger="true">
                            </ext:FieldTrigger>

                        </Triggers>
                        <Listeners>
                            <Select Handler="this.getTrigger(0).show();" />
                            <BeforeQuery Handler="this.getTrigger(0)[this.getRawValue().toString().length == 0 ? 'hide' : 'show']();" />
                            <TriggerClick Handler="if (index == 0) {
                                           this.clearValue();
                                           this.getTrigger(0).hide();
                                       }" />
                        </Listeners>
                        <Store>
                            <ext:Store
                                runat="server"
                                ID="stest">

                                <Model>
                                    <ext:Model ID="Model1" runat="server" IDProperty="DepartmentID">
                                        <Fields>
                                            <ext:ModelField Name="DepartmentID" Type="Int" />
                                            <ext:ModelField Name="DepartmentName" Type="String" />
                                        </Fields>
                                    </ext:Model>
                                </Model>
                            </ext:Store>
                        </Store>

                    </ext:ComboBox>
<ext:Button runat="server" ID="btnShow" Text="Show" OnClick="btnShow_Click" AutoPostBack="true">
    public partial class test : System.Web.UI.Page
    {
       
        protected void Page_Load(object sender, EventArgs e)
        {

            if (!X.IsAjaxRequest)
            {
                
                LoadCombo();


            }
           
        }

        


        protected void btnShow_Click(object sender, EventArgs e)
        {

           
        }

        private void LoadCombo()
        {
            Department d;
            List<Department> _d = new List<Department>();
            for (int i = 0; i <= 4; i++)
            {
                d = new Department();
                d.DepartmentID = i;
                d.DepartmentName = "Department - " + i.ToString();
                _d.Add(d);
            }
            

            stest.DataSource = _d;
            stest.DataBind();
			
			this.cmdtest.SelectedItems.Clear();
            this.cmdtest.Items.Insert(0, new Ext.Net.ListItem { Text = "All", Value = "0" });
            this.cmdtest.SelectedItems.Add(new Ext.Net.ListItem { Index = 0 });
        }
    }

    public class Department
    {
        public int DepartmentID { get; set; }
        public string DepartmentName { get; set; }
    }
    1. Run this code and select ,combobox first item get selected automatically.
    2. select a option suppose Department - 4,click on button again All option get selected.

    but if I remove 
    this.cmdtest.SelectedItems.Clear();
            this.cmdtest.Items.Insert(0, new Ext.Net.ListItem { Text = "All", Value = "0" });
            this.cmdtest.SelectedItems.Add(new Ext.Net.ListItem { Index = 0 });
    from LoadCombo() all works fine.
  10. #10
    Feb 16, 2015, 6:09 AM
    Please try to set QueryMode="Local" for the ComboBox.

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