I have a data grid that is created dynamically to display information retrieved from a database. The data grid consists of multiple bound columns and two button columns for each row, a view and a delete button.
Clicking either button calls the Page_Load() method with Page.IsPostBack as false.
if (!Page.IsPostBack)
{
this.bindForm(); // Populates drop down lists that the user can select
setAccess(false); // Sets access for the page
// Stuff commented out to avoid confusion
}
else
{
bindDynamicGrids(); // Create the data grid(s) and populate them
}
So when I first click the button the above code gets called with IsPostBack false, and the dynamic grids get bound. But, the button click event does not fire. When I click the button a second time, Page_Load is called with IsPostBack false, and after executing bindDynamicGrids() the button click event is fired. I cannot understand the difference between the first and second click.
I have read a few threads;
ASP.NET C#, need to press a button twice to make something happen
http://forums.asp.net/t/1783694.aspx?ASP+NET+Button+needs+to+be+clicked+twice
To attempt to understand the issue, but I must be missing something. From what I am gathering from the second link, a session variable may be getting set in the click event, which is also being set in Page_Load, and this is all an issue with ordering. If that is the case I am not seeing where it is happening.
When it is not a post back the bindForm() method is called, which populates all drop down lists. The edit click event populates those drop downs with the values from the row, but the click event is always a post back and the form has already been bound.
I have also considered having a script automatically double click one of the buttons anytime the user single clicks, but I have not been able to find an "OnClick" property for the column button. Any help that could be provided would be phenomenal.
The thing is, that the button click event happens after the Page_Load event meaning that the filtering does not get applied on the first postback. It has been updated on the second postback and you see the filtering.
You can try to move the code of your page_load event to OnPreRender so the reload happens after the button click event.
for more information look here: Button needs to be clicked twice
and here
Related
I am developing a Web application using C# with asp.net. I have a sub-view in a Multiview control, which can be 3 states.
I change an enumeration in code to determine the state of the page. This is done by clicking one of the three buttons.
But my problem is,
the button event will be fired after the page_load event, which loads the data of the page based on the enumeration, so the cycle goes as follows:
Click Button -> Load Page -> change enumeration.
So the changes won't be displayed. Only when i click the button a second time it shows the new data, because then the enumeration is changed and it loads. But I can't load the data in another event like Page_PreLoad because I'm dynamically creating controls with events, which won't work then. Thanks for helping!
I have a text box on a Gridview which I'm allowing some data to be edited. When the enter key is hit, the TextChanged event happens, like I'd expect. But when i change the data and click a button, the button effect not happen. I must click the button again to fire button event. I think it happen because the grid didnot lost it focus.
How to make it possible fire the button event just in one click?
You can change your gridview element's IsTabStop property to false to gain that effect.
Also if you want to cycle with Tab you can TabNavigation="Cycle" .
Both changes are in xaml.
Not much we can do to help you here without the code itself but here are couple things you could try to debug this:
Try different browsers – it may be a browser issue
Try some client side debugging – just open console and see if anything happens when you click the button for the first time
I have a grid which contains multiple columns/rows with ASP TextBox controls. In addition to this, above the grid I have a radio button list which contains years.
The user can enter numbers into the TextBoxes and then click an item on the RadioButton list to save the information then switch years or click an update button to just save the information and remain viewing the data.
If I click the 'save' button the textchanged event handler fires and I know what rows on my grid had something changed, then I update my DB and then get the data again to display to the user.
If however I click the radiobuttonlist to switch years the SelectedIndexChanged event fires but the TextChanged event handler does not run because the save and get data runs first, rebinding the grid and eventhandler.
This appears to me to be something to do with the way events run in .net, does anyone know how can I get the textchanged event handler to run first when clicking a radio button list?
I'm using VS2005, .Net 2.5, ASP.Net, C#
Thanks in advance
Your question is not clear. Anyway i can understand that you have problem with the event handlers and how they are called.
I want to know what is the need of calling the textchanged event and SelectedIndexChanged. Even they are not called your data would be get saved perfectly.
Every time I click an ASP button on my page to select an item in my dropdown list, it is only choosing the first item in the list. It is as if every time I click a button the page refreshes and all variables reset. How do you choose an item from a dropdown when using dynamic data from a database?
This sounds indicative of populating the DropDownList in Page_Load. Is that the case? (I'm assuming you're using WebForms.) If you're populating the control in Page_Load then you'll want to wrap it in a conditional:
if (!IsPostBack)
{
// populate your controls from data
}
Otherwise, they'll get re-populated with each postback. When you click a button or perform some other action on the page which initiates a postback, Page_Load is called before the event handler. So in effect, this is happening:
User navigates to the page
Page_Load clears and re-populates the DropDownList
User chooses an item in the DropDownList
User clicks a button
Page_Load clears and re-populates the DropDownList
Button handler gets the current selection from the DropDownList, which is the default.
What do you mean by "click ASP button"?
If you are talking about the downarrow to open the dropdown list, then you need to set AutoPostback options to false if you don't want that opening the dropdown list triggers postback (that is on the other side required if you have any events related to the opening of your list).
Have a dropdown list with autopostback set to 'yes' have another dropdown list box that will be populated based on the selection of the first dropdown. It works fine until I put a submit botton on the form. When I do it appears to not do the auto postback until the submit button is pushed. Can you have a submit button on a form that has a dropdown with autopostback active. thanks...
Sure you can.
Are you handling the autopostback event of the first dropdown in the code-behind file to populate the second dropdown? If so, your postback event should be firing when you change your selection in the first dropdown. Put a breakpoint in your code to assure that your event code is being called.
Sure you can. Are you seeing it not load the second dropdown? If so, check where you're handling that, as it may be in the wrong spot (if you're doing it with code) or you might have it wrapped in a !postback without thinking about it. Post more code and explanation for more help.