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Scrolling

If the RadListDataItems cannot fit in the popup a vertical scroll bar appears so that they can be scrolled and later selected. By default, the value of the EnableMouseWheel is set to true enabling scrolling through the items by using the mouse wheel.

KineticScrolling

This feature ensures that the control is ready for modern touch-screen applications. It can be attached by simply setting the EnableKineticScrolling to true.

Figure 1: Enable Kinetic Scrolling

WinForms RadDropDownList Enable Kinetic Scrolling

Enabling Kinetic Scrolling

this.radDropDownList1.EnableKineticScrolling = true;

Me.RadDropDownList1.EnableKineticScrolling = True

Programmatically Scrolling

RadDropDownList provides out of the box functionality for programmatically scrolling its content. The available methods are:

  • ScrollToItem: Scrolls to a specific item.

  • ScrollToActiveItem: Scrolls to the active item if it is not null and if it is not fully visible.

Figure 2: Scroll to Item

WinForms RadDropDownList Scroll to Item

Scroll to Item

this.radDropDownList1.DropDownListElement.ListElement.ScrollToItem(this.radDropDownList1.Items.Last());

Me.RadDropDownList1.DropDownListElement.ListElement.ScrollToItem(Me.RadDropDownList1.Items.Last())

Figure 3: Scroll to Active Item

WinForms RadDropDownList Scroll to Active Item

Scroll to Active Item

this.radDropDownList1.DropDownListElement.ListElement.ScrollToActiveItem();

Me.RadDropDownList1.DropDownListElement.ListElement.ScrollToActiveItem()

Scrolling Modes

The ListElement contained in the popup of RadDropDownList supports three types of ScrollModes:

  • Discrete: Defines scrolling by only one item at a time.

  • Smooth: Sets scrolling by pixel, meaning that an item can be partially visible.

  • Deferred: Does not cause GUI updates until the user finishes the scrolling operation.

Figure 4: Discrete Scrolling

WinForms RadDropDownList Discrete Scrolling

Discrete Scrolling

this.radDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Discrete;

Me.RadDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Discrete

Figure 5: Smooth Scrolling

WinForms RadDropDownList Smooth Scrolling

Smooth Scrolling

this.radDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Smooth;

Me.RadDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Smooth

Figure 6: Deferred Scrolling

WinForms RadDropDownList Deferred Scrolling

Deferred Scrolling

this.radDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Deferred;

Me.RadDropDownList1.DropDownListElement.ListElement.ScrollMode = ItemScrollerScrollModes.Deferred

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