If I add a target element after initialization, the ContextMenu cannot be opened for it. It seems like the ContextMenu cannot work with dynamic targets.
Reproduction: https://blazorrepl.telerik.com/wyaKvxaM02UinTjJ35.
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ADMIN EDIT
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A possible workaround is to dispose and recreate the ContextMenu after adding the new element during runtime: https://blazorrepl.telerik.com/coaUvdYs153SKyiQ29.
If you open a child menu via the keyboard, you can then hover over another parent and open a second submenu. The problem can be reproduced in the live demo.
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ADMIN EDIT
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The issue targets the Menu component as well.
Try to click an item in the context menu by clicking the icon instead of the text. The click doesn't register. It happens only with SVG icons.
Example use case is to have a context menu bound to a form item. The form item would re-render on submit that would change the dom element.
Example: https://blazorrepl.telerik.com/mxEnmnaV09ahp4EB15
Workaround: https://blazorrepl.telerik.com/mxkxwHOr08fcjSKK39
Hello,
Please consider an OnHide event for the ContextMenu. Here is a scenario - the target's styles change when the Menu opens. There is no reliable built-in event that one can use to revert the styles back. The user can click on a Menu item, but they can also click somewhere else or hit Escape.
Currently, a possible workaround is to listen for clicks and keypresses on the document with JavaScript:
When the menu shows on its own (it has a Selector and you right click that element), it tracks the z-index of other Telerik popups and has an inline z-index rule. This does not happen when you show it via its API (.ShowAsync()).
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ADMIN EDIT
A workaround could be using a CSS CLass to set a higher z-index to it, but there is an issue with that where it does not render high enough in the DOM: https://feedback.telerik.com/blazor/1514877-css-class-does-not-render-on-the-topmost-element. You can Vote for that and Follow it as well, and it contains a CSS workaround you can consider for this issue too. Note that it will affect all animation containers on the page.
Basic reproducible - showing a context menu on a grid row in a Window - the context menu is not visible behind the window (you can only see it partially in the last 1-2 rows).
<TelerikWindow Visible="true">
<WindowContent>
Copy code@using System.Collections.Generic
@using System.Collections.ObjectModel
<TelerikContextMenu @ref="@ContextMenuRef" Data="@MenuItems"
OnClick="@((MenuItem item) => ContextMenuClickHandler(item))">
</TelerikContextMenu>
<TelerikGrid Data="@GridData" @ref="@GridRef"
EditMode="@GridEditMode.Inline"
Height="500px"
Pageable="false"
OnCreate="@CreateItem" OnUpdate="@UpdateHandler"
OnRowContextMenu="@OnContextMenu"
SelectionMode="@GridSelectionMode.Multiple"
@bind-SelectedItems="@SelectedItems">
<GridToolBar>
<GridCommandButton Command="Add" Icon="add">Add Employee</GridCommandButton>
</GridToolBar>
<GridColumns>
<GridColumn Field=@nameof(SampleData.ID) Editable="false" />
<GridColumn Field=@nameof(SampleData.Name) />
<GridCommandColumn>
<GridCommandButton Command="Save" Icon="save" ShowInEdit="true">Update</GridCommandButton>
<GridCommandButton Command="Cancel" Icon="cancel" ShowInEdit="true">Cancel</GridCommandButton>
</GridCommandColumn>
</GridColumns>
</TelerikGrid>
@if (SelectedItems.Any())
{
<ul>
@foreach (var item in SelectedItems)
{
<li>@item.Name</li>
}
</ul>
}
@code {
//data sources
ObservableCollection<SampleData> GridData { get; set; }
List<MenuItem> MenuItems { get; set; }
IEnumerable<SampleData> SelectedItems { get; set; } = Enumerable.Empty<SampleData>();
//metadata for the context menu actions
SampleData SelectedPerson { get; set; }
//component references so we can use their methods
TelerikContextMenu<MenuItem> ContextMenuRef { get; set; }
TelerikGrid<SampleData> GridRef { get; set; }
// sample menu item class
public class MenuItem
{
public string Text { get; set; }
public string Icon { get; set; }
public Action Action { get; set; }
public string CommandName { get; set; }
}
// show the context menu for a particular row
async Task OnContextMenu(GridRowClickEventArgs args)
{
var argsItem = args.Item as SampleData;
SelectedPerson = argsItem;
if (args.EventArgs is MouseEventArgs mouseEventArgs)
{
await ContextMenuRef.ShowAsync(mouseEventArgs.ClientX, mouseEventArgs.ClientY);
}
}
// sample handling of the context menu click
async Task ContextMenuClickHandler(MenuItem item)
{
// one way to pass handlers is to use an Action, you don't have to use this
if (item.Action != null)
{
item.Action.Invoke();
}
else
{
// or you can use local code to perform a task
// such as put a row in edit mode or select it
switch (item.CommandName)
{
case "BeginEdit": // read more at https://localhost/blazor-ui/components/grid/state#initiate-editing-or-inserting-of-an-item
var currState = GridRef.GetState();
currState.InsertedItem = null;
SampleData itemToEdit = SampleData.GetClonedInstance(GridData.Where(itm => itm.ID == SelectedPerson.ID).FirstOrDefault());
currState.OriginalEditItem = itemToEdit;
await GridRef.SetState(currState);
break;
case "ToggleSelect":
var selItems = SelectedItems.ToList();
if (SelectedItems.Contains(SelectedPerson))
{
selItems.Remove(SelectedPerson);
}
else
{
selItems.Add(SelectedPerson);
}
SelectedItems = selItems;
break;
default:
break;
}
}
SelectedPerson = null; // clean up
}
// generate data
protected override void OnInitialized()
{
// context menu items
MenuItems = new List<MenuItem>()
{
new MenuItem(){ Text = "Select", Icon="checkbox-checked", CommandName="ToggleSelect" },
new MenuItem(){ Text = "Edit", Icon="edit", CommandName="BeginEdit" },
new MenuItem(){ Text = "Delete", Icon="delete", Action = DeleteItem }
};
// generate data for the grid
GridData = new ObservableCollection<SampleData>();
var rand = new Random();
for (int i = 0; i < 100; i++)
{
GridData.Add(new SampleData()
{
ID = i,
Name = "Employee " + i.ToString(),
});
}
}
// CUD operations for the grid
async Task CreateItem(GridCommandEventArgs args)
{
var argsItem = args.Item as SampleData;
// call the actual data service here
argsItem.ID = GridData.Count + 1;
GridData.Insert(0, argsItem);
}
void DeleteItem() // not async so it can be passed as an Action
{
var argsItem = SelectedPerson;
// call the actual data service here
GridData.Remove(argsItem);
}
async Task UpdateHandler(GridCommandEventArgs args)
{
var argsItem = args.Item as SampleData;
// call the actual data service here
var index = GridData.ToList().FindIndex(i => i.ID == argsItem.ID);
if (index != -1)
{
GridData[index] = argsItem;
}
}
public class SampleData
{
public int ID { get; set; }
public string Name { get; set; }
public override bool Equals(object obj)
{
if (obj is SampleData)
{
return this.ID == (obj as SampleData).ID;
}
return false;
}
public SampleData()
{
}
public SampleData(SampleData itmToClone)
{
this.ID = itmToClone.ID;
this.Name = itmToClone.Name;
}
public static SampleData GetClonedInstance(SampleData itmToClone)
{
return new SampleData(itmToClone);
}
}
}
</WindowContent>
</TelerikWindow>
Based on the sample app "BlazingCoffee" (where you can reproduce this bug), when I add a ContextMenu in the grid Sales, using OnRowContextMenu of TelerikGrid, there's an asynchrony in the behavior of telerik-blazor.js when it open the popup of the ContextMenu and when it try to focus it.
The bug consists in the fact that when I have a vertically long grid, with an active scrollbar, if I right-click on the first row to open the ContextMenu, the app first try to focus it, does not find it, then scroll the page to the bottom and after all this it open the popup of the ContextMenu in the right position. So you need to scroll back to row where you right-clicked to visualize the ContextMenu.
In general, it try always to focus to the first element of the ContextMenu and after that it open the new ContextMenu in the right position, letting it focus the page in the wrong position.
WORKAROUND:
To solve this wrong behavior I deleted the last line of code of the method "focusFirstMenuItem" of "telerik-blazor.js". If I remove "t&&t.focus()", the ContextMenu works perfectly, without unwanted scrolling.
I hope you can resolve this soon.
Angelo Marzullo
P.S. Telerik version: 2.24.0
The Class does not render on the topmost element so you can't properly set css rules like z-index to the context menu.
A workaround is to set a higher z-index to all animation containers with a rule like this:
.k-animation-container {
z-index: 987654;
}
Please allow the context menu to be used without a data source and run using templates only.
That way we can use this control to provide a popup of items that we can control, and don't have to set it up with sometime of blank list of items that are never used.
When using Template there's no way to trigger a close of the ContextMenu when clicking inside the template.
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ADMIN EDIT
Marked as duplicated, because the feature will be implemented in ContextMenu and Menu component at once. For better tracking, we will keep the item logged for the Menu component.
Sample workaround:
@inject IJSRuntime _js
<script suppress-error="BL9992">
function hideMenu(menuClass) {
setTimeout(function () {
var menuParent = document.querySelector("." + menuClass);
if (menuParent) {
menuParent.dispatchEvent(new KeyboardEvent('keydown', { 'key': 'Escape' }));
}
}, 50);
}
</script>
<div class="menuTarget">
right click this target
</div>
<style>
.menuTarget {
width: 100px;
background: yellow;
margin: 50px;
}
</style>
<TelerikContextMenu Data="@MenuItems" @ref="@TheContextMenu" Selector=".menuTarget" Class="@menuClass">
<Template>
<TelerikButton OnClick="@HideMenu">Hide Menu</TelerikButton>
</Template>
</TelerikContextMenu>
@code {
string menuClass = "my-context-menu";
async Task HideMenu()
{
await _js.InvokeVoidAsync("hideMenu", menuClass);
}
// sample data binding
public List<ContextMenuItem> MenuItems { get; set; }
TelerikContextMenu<ContextMenuItem> TheContextMenu { get; set; }
bool UseSpecialMenu { get; set; }
async Task ShowContextMenu(MouseEventArgs e)
{
await TheContextMenu.ShowAsync(e.ClientX, e.ClientY);
}
// generate sample data for the listview and the menu
protected override void OnInitialized()
{
MenuItems = new List<ContextMenuItem>()
{
new ContextMenuItem
{
Text = "More Info",
Metadata = "info"
},
new ContextMenuItem
{
Text = "Special Command",
Metadata = "special"
}
};
base.OnInitialized();
}
public class ContextMenuItem
{
public string Text { get; set; }
public string Metadata { get; set; }
}
}
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