Intersoft Community - Lounge - WebTreeview Scroll Position

WebTreeview Scroll Position

erwinintersoft — Tue, 15 Mar 2016 11:48:46 GMT

Hi Shailendra,

you could set the button function similiar to TreeView NodeSelect, for example:

function ApplyLatestScroll() {    var treeView = ISGetObject("WebTreeView1");    var frameElement = treeView.GetFrameElement();    frameElement.children[0].scrollTop = form1.ValueHiddenField.value;

    return true;
}

After that, invoke the ApplyLatestScroll() function from OnInitializeNode event.

protected void WebTreeView1_InitializeNode(object sender, ISNet.WebUI.WebTreeView.WebTreeViewNodeEventArgs e) {
     Page.ClientScript.RegisterStartupScript(this.GetType(), "ApplyLatestScroll", "ApplyLatestScroll();", true);
 }

Hope this helps.

Best Regards,
Erwin Sanders

WebTreeview Scroll Position

shailendra.senger — Fri, 11 Mar 2016 19:48:04 GMT

Thanks Yudi. Is there a way to maintain scroll on a button postback. I tried to call ApplyLatestScroll function in Button click but it is not working. I need to maintain scroll at button click as well. Please help.

WebTreeview Scroll Position

yudi — Sun, 28 Feb 2016 19:23:41 GMT

OnNodeSelect client-side event of WebTreeView is used to collect the last position of the vertical scrollbar by obtaining the scrollTop property then store the value in HiddenField control. The OnNodeSelect client-side event specifies the client side (JavaScript) function name that will be invoked when node is selected. Parameters: (controlsId, node).

function WebTreeView1_OnNodeSelect(controlId, node)
{
    // collecting the last position
    // of the vertical scrollbar
    // by obtaining the scrollTop property

    var treeView = ISGetObject(controlId);
    var frameElement = treeView.GetFrameElement();

    // obtain the scrollTop property 
    // of the vertical scrollbar
    var verticalPosition = frameElement.children[0].scrollTop;

    // store the value scrollTop position in HiddenField control
    form1.ValueHiddenField.value = verticalPosition;

    return true;
}

Next, invoke the ApplyLatestScroll() JavaScript function from OnNodeSelectChanged event.

protected void WebTreeView1_NodeSelectChanged(object sender, ISNet.WebUI.WebTreeView.WebTreeViewNodeEventArgs e)
{
    // This event fires after the selected treeview nodes are changed.

    // invoke ApplyLatestScroll() function to set back the scroll position.
    Page.ClientScript.RegisterStartupScript(this.GetType(), "ApplyLatestScroll", "ApplyLatestScroll();", true);
}

The ApplyLatestScroll() JavaScript function is:

function ApplyLatestScroll()
{
    // set back the previous scrollTop property or
    // vertical scroll position

    var treeView = ISGetObject("WebTreeView1");
    var frameElement = treeView.GetFrameElement();
            
    // manually configure the vertical scroll position
    frameElement.children[0].scrollTop = form1.ValueHiddenField.value;

    return true;
}

I enclosed my simple sample for your reference. Please let me know whether this helps or not.

WebTreeview Scroll Position

shailendra.senger — Fri, 26 Feb 2016 23:16:58 GMT

How to maintain WebTreeView scroll position on the postback caused by selected node.

Please answer.