| Client-Side API Reference > Input > wijmo.input > Menu Class |
constructor(element: any, options?): Menu
Initializes a new instance of the Menu class.
The DOM element that hosts the control, or a selector for the host element (e.g. '#theCtrl').
The JavaScript object containing initialization data for the control.
Gets or sets a value that indicates whether the control should automatically expand the selection to whole words/numbers when the control is clicked.
Gets the ICollectionView object used as the item source.
Gets or sets the command to execute when an item is clicked.
Commands are objects that implement two methods:
You can also set commands on individual items using the commandPath property.
Gets or sets the name of the property that contains a parameter to use with the command specified by the commandPath property.
Gets or sets the name of the property that contains the command to execute when the user clicks an item.
Commands are objects that implement two methods:
Gets or sets the template used to instantiate DropDown controls.
Gets or sets the name of the property to use as the visual representation of the items.
Gets the drop down element shown when the isDroppedDown property is set to true.
Gets or sets a CSS class name to add to the control's drop-down element.
This property is useful when styling the drop-down element, because it is shown as a child of the document body rather than as a child of the control itself, which prevents using CSS selectors based on the parent control.
Event that fires when items in the drop-down list are created.
You can use this event to modify the HTML in the list items. For details, see the formatItem event.
Gets or sets the name of a property to use for getting the value displayed in the control's input element.
The default value for this property is null, which causes the control to display the same content in the input element as in the selected item of the drop-down list.
Use this property if you want to de-couple the value shown in the input element from the values shown in the drop-down list. For example, the input element could show an item's name and the drop-down list could show additional detail.
Gets the DOM element that is hosting the control.
Gets the HTML input element hosted by the control.
Use this property in situations where you want to customize the attributes of the input element.
Gets or sets a value that indicates whether the control should use a fade-in animation when displaying the drop-down.
Gets or sets a value that determines whether this Menu should act as a split button instead of a regular menu.
The difference between regular menus and split buttons is what happens when the user clicks the menu header. In regular menus, clicking the header shows or hides the menu options. In split buttons, clicking the header raises the itemClicked event and/or invokes the command associated with the last option selected by the user as if the user had picked the item from the drop-down list.
If you want to differentiate between clicks on menu items and the button part of a split button, check the value of the isDroppedDown property of the event sender. If that is true, then a menu item was clicked; if it is false, then the button was clicked.
For example, the code below implements a split button that uses the drop-down list only to change the default item/command, and triggers actions only when the button is clicked:
<-- view -->
<wj-menu is-button="true" header="Run" value="browser"
item-clicked="itemClicked(s, e)">
<wj-menu-item value="'Internet Explorer'">Internet Explorer</wj-menu-item>
<wj-menu-item value="'Chrome'">Chrome</wj-menu-item>
<wj-menu-item value="'Firefox'">Firefox</wj-menu-item>
<wj-menu-item value="'Safari'">Safari</wj-menu-item>
<wj-menu-item value="'Opera'">Opera</wj-menu-item>
</wj-menu>
// controller
$scope.browser = 'Internet Explorer';
$scope.itemClicked = function (s, e) {
// if not dropped down, click was on the button
if (!s.isDroppedDown) {
alert('running ' + $scope.browser);
}
}
Gets or sets a value indicating whether the drop-down list displays items as plain text or as HTML.
Gets or sets a value that determines whether the control is disabled.
Disabled controls cannot get mouse or keyboard events.
Gets or sets a value that indicates whether the drop down is currently visible.
Gets or sets a value that enables or disables editing of the text in the input element of the ComboBox (defaults to false).
Gets or sets a value that indicates whether the user can modify the control value using the mouse and keyboard.
Gets or sets a value that determines whether the control value must be set to a non-null value or whether it can be set to null (by deleting the content of the control).
Gets a value that indicates whether the control is currently handling a touch event.
Gets a value that indicates whether the control is currently being updated.
Gets or sets a function used to customize the values shown in the drop-down list. The function takes two arguments, the item index and the default text or html, and returns the new text or html to display.
If the formatting function needs a scope (i.e. a meaningful 'this' value), then remember to set the filter using the 'bind' function to specify the 'this' object. For example:
comboBox.itemFormatter = customItemFormatter.bind(this);
function customItemFormatter(index, content) {
if (this.makeItemBold(index)) {
content = '<b>' + content + '</b>';
}
return content;
}
Gets or sets the array or ICollectionView object that contains the items to select from.
Gets or sets the maximum height of the drop-down list.
Gets or sets the maximum width of the drop-down list.
The width of the drop-down list is also limited by the width of the control itself (that value represents the drop-down's minimum width).
Gets or sets the element that owns this Menu.
This variable is set by the wj-context-menu directive in case a single menu is used as a context menu for several different elements.
Gets or sets the string shown as a hint when the control is empty.
Gets a value indicating whether the control is hosted in an element with right-to-left layout.
Gets or sets the index of the currently selected item in the drop-down list.
Gets or sets the item that is currently selected in the drop-down list.
Gets or sets the value of the selectedItem, obtained using the selectedValuePath.
Gets or sets the name of the property used to get the selectedValue from the selectedItem.
Gets or sets a value that indicates whether the control should display a drop-down button.
addEventListener(target: EventTarget, type: string, fn: any, capture?: boolean): void
Adds an event listener to an element owned by this Control.
The control keeps a list of attached listeners and their handlers, making it easier to remove them when the control is disposed (see the dispose and removeEventListener method).
Failing to remove event listeners may cause memory leaks.
Target element for the event.
String that specifies the event.
Function to execute when the event occurs.
Whether the listener is capturing.
applyTemplate(classNames: string, template: string, parts: Object, namePart?: string): HTMLElement
Applies the template to a new instance of a control, and returns the root element.
This method should be called by constructors of templated controls. It is responsible for binding the template parts to the corresponding control members.
For example, the code below applies a template to an instance of an InputNumber control. The template must contain elements with the 'wj-part' attribute set to 'input', 'btn-inc', and 'btn-dec'. The control members '_tbx', '_btnUp', and '_btnDn' will be assigned references to these elements.
this.applyTemplate('wj-control wj-inputnumber', template, {
_tbx: 'input',
_btnUp: 'btn-inc',
_btnDn: 'btn-dec'
}, 'input');
Names of classes to add to the control's host element.
An HTML string that defines the control template.
A dictionary of part variables and their names.
Name of the part to be named after the host element. This determines how the control submits data when used in forms.
beginUpdate(): void
Suspends notifications until the next call to endUpdate.
deferUpdate(fn: Function): void
Executes a function within a beginUpdate/endUpdate block.
The control will not be updated until the function has been executed. This method ensures endUpdate is called even if the function throws an exception.
Function to be executed.
dispose(): void
Disposes of the control by removing its association with the host element.
The dispose method automatically removes any event listeners added with the addEventListener method.
Calling the dispose method is important in applications that create and remove controls dynamically. Failing to dispose of the controls may cause memory leaks.
disposeAll(e?: HTMLElement): void
Disposes of all Wijmo controls contained in an HTML element.
Container element.
endUpdate(): void
Resumes notifications suspended by calls to beginUpdate.
getControl(element: any): Control
Gets the control that is hosted in a given DOM element.
The DOM element that is hosting the control, or a selector for the host element (e.g. '#theCtrl').
getDisplayText(index?: number): string
Gets the string displayed in the input element for the item at a given index (always plain text).
The index of the item to retrieve the text for.
getTemplate(): string
Gets the HTML template used to create instances of the control.
This method traverses up the class hierarchy to find the nearest ancestor that specifies a control template. For example, if you specify a prototype for the ComboBox control, it will override the template defined by the DropDown base class.
hide(): void
Hides the menu.
This method is useful if you want to hide a context menu displayed with the show method.
indexOf(text: string, fullMatch: boolean): number
Gets the index of the first item that matches a given string.
initialize(options: any): void
Initializes the control by copying the properties from a given object.
This method allows you to initialize controls using plain data objects instead of setting the value of each property in code.
For example:
grid.initialize({
itemsSource: myList,
autoGenerateColumns: false,
columns: [
{ binding: 'id', header: 'Code', width: 130 },
{ binding: 'name', header: 'Name', width: 60 }
]
});
// is equivalent to
grid.itemsSource = myList;
grid.autoGenerateColumns = false;
// etc.
The initialization data is type-checked as it is applied. If the initialization object contains unknown property names or invalid data types, this method will throw.
Object that contains the initialization data.
invalidate(fullUpdate?: boolean): void
Invalidates the control causing an asynchronous refresh.
Whether to update the control layout as well as the content.
invalidateAll(e?: HTMLElement): void
Invalidates all Wijmo controls contained in an HTML element.
Use this method when your application has dynamic panels that change the control's visibility or dimensions. For example, splitters, accordions, and tab controls usually change the visibility of its content elements. In this case, failing to notify the controls contained in the element may cause them to stop working properly.
If this happens, you must handle the appropriate event in the dynamic container and call the invalidateAll method so the contained Wijmo controls will update their layout information properly.
Container element. If set to null, all Wijmo controls on the page will be invalidated.
onGotFocus(e?: EventArgs): void
Raises the gotFocus event.
onIsDroppedDownChanged(e?: EventArgs): void
Raises the isDroppedDownChanged event.
onIsDroppedDownChanging(e: CancelEventArgs): boolean
Raises the isDroppedDownChanging event.
onItemClicked(e?: EventArgs): void
Raises the itemClicked event.
onLostFocus(e?: EventArgs): void
Raises the lostFocus event.
onSelectedIndexChanged(e?: EventArgs): void
Raises the selectedIndexChanged event.
onTextChanged(e?: EventArgs): void
Raises the textChanged event.
refresh(fullUpdate?: boolean): void
Refreshes the control.
Whether to update the control layout as well as the content.
refreshAll(e?: HTMLElement): void
Refreshes all Wijmo controls contained in an HTML element.
This method is similar to invalidateAll, except the controls are updated immediately rather than after an interval.
Container element. If set to null, all Wijmo controls on the page will be invalidated.
removeEventListener(target?: EventTarget, type?: string, fn?: any, capture?: boolean): number
Removes one or more event listeners attached to elements owned by this Control.
Target element for the event. If null, removes listeners attached to all targets.
String that specifies the event. If null, removes listeners attached to all events.
Handler to remove. If null, removes all handlers.
Whether the listener is capturing. If null, removes capturing and non-capturing listeners.
selectAll(): void
Sets the focus to the control and selects all its content.
show(position?: any): void
Shows the menu at a given location.
This method is useful if you want to use the menu as a context menu, attached to one or more elements on the page. For example:
// create menu
var div = document.createElement('div');
var menu = new wijmo.input.Menu(div, {
itemsSource: 'New,Open,Save,Exit'.split(','),
itemClicked: function (s, e) {
alert('thanks for picking ' + menu.selectedIndex);
}
});
// use it as a context menu for one or more elements
var element = document.getElementById('btn');
element.addEventListener('contextmenu', function (e) {
e.preventDefault();
menu.show(e);
});
An optional MouseEvent or reference element that determines the position where the menu should be displayed. If not provided, the menu is displayed at the center of the screen.
Occurs after the drop down is shown or hidden.
Occurs before the drop down is shown or hidden.
Occurs when the user picks an item from the menu.
The handler can determine which item was picked by reading the event sender's selectedIndex property.
Occurs when the value of the selectedIndex property changes.
The Menu control shows a text element with a drop-down list of commands that the user can invoke by click or touch.
The Menu control inherits from ComboBox, so you populate and style it in the same way that you do the itemsSource property).
The itemClicked event that fires when the user selects an item from the menu. The event handler can inspect the Menu control to determine which item was clicked. For example:
var menu = new wijmo.input.Menu(hostElement); menu.header = 'Main Menu'; menu.itemsSource = ['option 1', 'option 2', 'option 3']; menu.itemClicked.addHandler(function(sender, args) { var menu = sender; alert('Thanks for selecting item ' + menu.selectedIndex + ' from menu ' + menu.header + '!'); });The example below illustrates how you can create value pickers, command-based menus, and menus that respond to the itemClicked event. The menus in this example are based on HTML <select;> and <option;> elements.
Example