bajaux Module: bajaux/Widget

The base Widget class, used for loading Web based Niagara Widgets.

A Widget contains the most basic mechanisms necessary for displaying user
interface upon a DOM element. It should not be instantiated directly,
but rather subclassed with the specific functionality you need.

At a bare minimum, either the doInitialize or doLoad function will need
to be implemented by your subclass.

Parameters:

Name Type Argument Description

params

Object

a parameters object.

Properties

Name	Type	Argument	Default	Description
`properties`	Object	<optional>		properties to add to this editor's underlying `bajaux/Properties` instance.
`enabled`	Boolean	<optional>		false to disable this editor
`readonly`	Boolean	<optional>		true to readonly this editor
`formFactor`	String	<optional>		form factor this editor should use (c.f. `Widget.formfactor`)
`keyName`	String	<optional>		the key name that bajaux should use to look up lexicon entries for this editor
`moduleName`	String	<optional>	'bajaux'	the module name that bajaux should use to look up lexicon entries for this editor
`data`	Object	<optional>		optional additional configuration data that may be used on a per-widget basis. This will often be used in conjunction with `fe`.
`params`	Object	<optional>		in conjunction with `defaults`, allows a Widget subclass to accept parameters passed to the constructor as well as an initial set of default values. See example.
`defaults`	Object	<optional>		in conjunction with `params`, allows a Widget subclass to define an initial set of default values. See example.

Mixes In:

tinyevents

Examples

Construct a Widget, defining its initial configuration with an object literal.

const w = new Widget({
  readonly: true,
  properties: { foo: 'bar' },
  formFactor: 'compact'
});

Define a Widget subclass with an initial set of default values, while still allowing parameters to be passed to the constructor. This is the preferred method of calling a Widget super-constructor.

class MyButton extends Widget {
  constructor(params) {
    super({
      params,
      defaults: {
        moduleName: 'myModule',
        keyName: 'MyButton',
        properties: { borderRadius: 15, padding: 10 }
      }
    });
  }
}
const button = new MyButton({ properties: { padding: 20 } });
button.properties().getValue('borderRadius'); // 15, from defaults
button.properties().getValue('padding'); // 20, from constructor

params and defaults will be correctly processed even when subclassing.

class AWidget extends Widget {
  constructor(params) {
    super({ params, defaults: { properties: { name: 'A' } } });
  }
}
class BWidget extends AWidget {
  constructor(params) {
    // defaults will be merged in with superclass defaults.
    super({ params, defaults: { properties: { name: 'B' } } });
  }
}
new BWidget().properties().getValue('name'); // 'B'
new BWidget({ properties: { name: 'Bee' } }).properties().getValue('name'); // 'Bee'

Requires

Members

<static> css

Widget CSS class names.

Properties:

Name	Type	Description
`initialized`	String	`bajaux-initialized`: applied after the widget is initialized.
`disabled`	String	`bajaux-disabled`: applied when the widget is disabled.
`designTime`	String	`bajaux-design-time`: Applied to an ancestor DOM element to indicate the widget is running in a graphic design editor. You can use this to style your widget differently between design time and production.
`readonly`	String	`bajaux-readonly`: Applied when the widget is marked readonly.b
`max`	String	`bajaux-max`: A large Widget (e.g. a View).
`compact`	String	`bajaux-compact`: A medium sized Widget (e.g. a dashboard Widget).
`mini`	String	`bajaux-mini`: A small Widget (e.g. a Field Editor).

<static> formFactor

Widget form-factors.

Properties:

Name	Type	Description
`max`	String	A large Widget (e.g. a View).
`compact`	String	A medium sized Widget (e.g. a dashboard Widget).
`mini`	String	A small Widget (e.g. a Field Editor).

See:

module:bajaux/Widget#getFormFactor

Methods

<static> in(el)

Find the Widget instance living in this DOM element.

Parameters:

Name	Type	Description
`el`	JQuery \| HTMLElement

Since:

Niagara 4.6

Returns:

Type: module:bajaux/Widget | undefined

applyParams( [params])

Can re-apply certain params that can also be passed to the constructor.

Parameters:

Name Type Argument Description

params

Object

Properties

Name	Type	Argument	Default	Description
`readonly`	Boolean	<optional>
`enabled`	Boolean	<optional>	true	must explicitly set to false to disable
`properties`	Object	<optional>

Since:

Niagara 4.10

Returns:

promise to be resolved after any
setEnabled/setReadonly work is done. Note that these functions will not
be called if the value of enabled/readonly is not actually changing.

Type: Promise

changed(name, value)

Called whenever a Widget's Property is changed.

This function should not typically be overridden.
doChanged() should be overridden
instead.

Parameters:

Name	Type	Description
`name`	String	The name of the Property that's changed.
`value`	*	The new Property value.

See:

module:bajaux/Widget#properties

Returns:

Type: Promise

cleanupDom()

Called to clean up the DOM when the widget is being destroyed.

This method can be overridden if DOM clean up needs to be
handled in a different way.

destroy()

Indicates that a widget is no longer needed and is in the process of being
removed. In this function, subclasses can deallocate any resources, event
handlers, etc. that they may be holding. Delegates the actual work to
doDestroy.

This method will not typically be overridden. doDestroy() should be
overridden instead.

Triggers a bajaux:destroy or bajaux:destroyfail event, as appropriate.

Please note, after doDestroy has resolved, the DOM will be emptied,
all event handlers will removed and the 'widget' data stored on the
DOM element will be deleted.

See:

module:bajaux/Widget#doDestroy

Returns:

A promise to be resolved when the widget has been
destroyed

Type: Promise

doChanged(name, value)

Called by changed() when a Property
is changed.

This method is designed to be overridden by any subclasses.

Parameters:

Name	Type	Description
`name`	String	The name of the Property that's changed.
`value`	*	The new Property value.

Returns:

Type: Promise | *

doDestroy( [params])

Called by destroy so this widget has a chance to clean up after itself
and release any resources it is holding.

Notably, any jQuery event handlers registered on child elements of the
widget's DOM element should be unregistered here. Also, you may want to
remove any CSS classes you've added to the widget's DOM element.

Parameters:

Name	Type	Argument	Description
`params`	Object	<optional>	Optional params object passed to `destroy()`

See:

module:bajaux/Widget#destroy

Returns:

An optional promise that's resolved once the widget
has been destroyed.

Type: * | Promise

doEnabled(enabled)

Called when the widget is enabled/disabled.

Parameters:

Name	Type	Description
`enabled`	Boolean	the new enabled state.

Returns:

An optional Promise that can be returned if
the state change is asynchronous.

Type: * | Promise

doInitialize(element [, params])

Performs the actual work of initializing the DOM element in which this
widget will live. This function should be overridden by subclasses - the
subclass function should append elements to element as
necessary and then optionally return a promise.

Most commonly, this will involve building up the HTML structure
necessary to load in a value. If this widget will display/edit a String,
for example, doInitialize might append a text input element to
the target element. A DynamicEnum might include a
<select> dropdown.

In some cases, no initialization may be required at all. This
might be the case if you are binding the widget to an HTML element that is
already pre-populated with all the necessary structure to load a value,
or maybe doLoad will empty out the element completely
and rebuild it from scratch every time a new value is loaded. In this
case, you do not need to override this method. (However, a widget that
overrides neither doInitialize nor doLoad will not be very useful!)

Tip: the promises returned by setEnabled and setReadonly can
only ever resolve after initialize itself resolves. So
return this.setEnabled(enabled) or return this.setReadonly(readonly)
from doInitialize will result in a deadlock that will never resolve.
They may be called, but not returned.

Parameters:

Name	Type	Argument	Description
`element`	JQuery		The element in which this Widget should build its HTML.
`params`	Object	<optional>	Optional params object passed into `initialize()`.

See:

module:bajaux/Widget#initialize

Returns:

An optional promise to be resolved once the Widget
has initialized.

Type: * | Promise

doLayout( [params])

Called when the layout of the Widget changes. This method is designed
to be overridden.

Parameters:

Name	Type	Argument	Description
`params`	*	<optional>	as of Niagara 4.10, any parameters passed to `layout()` will also be passed to `doLayout()`.

Returns:

This method may optionally return a promise once the
Widget has been laid out.

Type: * | Promise

doLoad(value [, params])

Performs the actual work of populating the widget's HTML to reflect the
input value.

This function should be overridden by subclasses. The subclass function
should manipulate the DOM jq() and,
optionally,return a promise to indicate that the work of loading the value
has completed.

Parameters:

Name	Type	Argument	Description
`value`	*		The value to be loaded.
`params`	Object	<optional>	Optional params object passed to `load()`

See:

Returns:

An optional promise that's resolved once the widget has
loaded.

Type: Promise

doModified(modified)

The actual implementation for setModified. This function
should do any work necessary when the widget is set to a modified or
"dirty" state - typically enabling a save button, arming a
window.onbeforeunload handler, etc. Likewise, it should do
the opposite when setting modified to false.

Note that this is synchronous, as is setModified. Async work can be
performed, but setModified will not wait for it.

Parameters:

Name	Type	Description
`modified`	Boolean

See:

module:bajaux/Widget#setModified

doRead()

Does the work of reading the widget's current representation.

This might mean reading a series of text inputs and assembling their
values into an array. It might mean instantiating a copy of the backing
baja.Component and setting slot values on the new copy.
It might mean simply returning the boolean value of a checkbox. If your
widget is composed of pure text/HTML and is not actually backed by an
external value, it might mean returning nothing.

When saving a modified widget, the output of this function will be passed
directly into this widget's validation process, so all your validation
steps should be expecting to receive this. It will also be passed to
doSave, so your doSave implementation should also expect this value.

The default behavior of doRead is simply to use the widget's current
value.

See:

module:bajaux/Widget#read

Returns:

The read value, or a promise to be resolved with the
read value

Type: * | Promise

doReadonly(readonly)

Called when the widget is set to readonly or made writable.

Parameters:

Name	Type	Description
`readonly`	Boolean	the new readonly state.

Returns:

An optional Promise that can be returned if
the state change is asynchronous.

Type: * | Promise

doSave(validValue [, params])

Performs the actual work of saving the widget. This function should
be overridden by subclasses to save the value. The subclass function
should save the value and then, optionally, return a promise to indicate
that the work of saving the widget has completed.

Parameters:

Name	Type	Argument	Description
`validValue`	*		The value to be used for saving. This value will have been read from the widget using `read()` and validated using `validate()`.
`params`	Object	<optional>	Optional params object passed to `save()`

Returns:

An optional promise that's resolved once
the widget has saved.

Type: * | Promise

generateId()

Generate a unique DOM ID. The ID will include the name of this widget's
constructor just for tracing/debugging purposes.

Returns:

Type: String

getChildWidgets( [params])

Returns an array of child widgets living inside this editor's DOM.
This method will specifically not return child widgets of child widgets

for instance, if this widget has one child editor for a baja.Facets,
you will only get a single widget back - it won't recurse down and give
you all the tag editors, type editors etc.

This is safer and easier than using $.find(), which recurses down,
or carefully managing strings of $.children() calls.

Pass in a jQuery instance to limit the child editor search to
a particular set of elements. Otherwise, will search all child elements
of this editor's DOM.

If this editor has not initialized yet, you'll just get an empty array
back.

The returned array will have some utility functions attached that return
promises. See example for details.

Parameters:

Name Type Argument Description

params

Object | jQuery

Properties

Name	Type	Argument	Default	Description
`dom`	JQuery	<optional>	this.jq().children()	the dom element to search
`type`	function	<optional>		the widget type to search for - pass in the actual constructor, for `instanceof` checks

Since:

Niagara 4.10

Returns:

an array of child widgets

Type: Array.<module:bajaux/Widget>

Examples

var kids = ed.getChildWidgets();
  kids.setAllEnabled(false).then(function () {});
  kids.setAllModified(false).then(function () {});
  kids.setAllReadonly(false).then(function () {});
  kids.readAll().then(function (valuesArray) {});
  kids.validateAll().then(function (valuesArray) {});
  kids.saveAll().then(function () {});
  kids.destroyAll().then(function () {});

var stringEditors = ed.getChildWidgets({ type: StringEditor });

getCommandGroup()

Return the widget's command group.

Returns:

Type: module:bajaux/commands/CommandGroup

getFormFactor()

Return the widget's form-factor. The form-factor
is normally passed in from the Widget's constructor. However,
it can be set from a 'formFactor' property if required.

A widget's form-factor typically doesn't change during a widget's
life-cycle.

See:

module:bajaux/Widget.formfactor

Returns:

The form-factor.

Type: String

hasMixIn(mixin)

Return true if the widget implements the specified MixIn.

Parameters:

Name	Type	Description
`mixin`	String	the name of the mixin to test for.

Returns:

Type: Boolean

initialize(dom [, params] [, layoutParams])

Initializes the DOM element to be bound to this Widget.

In a nutshell, initialize defines the following contract:

After initialize completes and calls
deferred.resolve, the target element will be fully initialized,
structured, and ready to load in a value. It will be accessible by
calling this.jq().
If this is an editor, load may not be called until
initialize's promise is resolved. Attempting
to load a value prior to initialization will result in failure.
This widget will be set as a jQuery data value on the initialized
DOM element. It can be retrieved by calling Widget.in(element).

initialize delegates the actual work of building the
HTML structure (if any) to the doInitialize function. When
subclassing Widget, you should not override initialize.
doInitialize should be overridden.

After initialize completes, an bajaux:initialize or
bajaux:initializefail event will be triggered, as appropriate. Will also
emit an initialized tinyevent.

initialize will always reject if the widget has already been destroyed.

Parameters:

Name	Type	Argument	Description
`dom`	JQuery		The jQuery DOM element in which this widget should build its HTML (will be passed directly to `doInitialize`)
`params`	*	<optional>	optional parameters object to be passed through to `doInitialize`
`layoutParams`	*	<optional>	as of Niagara 4.10, optional parameters object to be passed through to `layout`

See:

module:bajaux/Widget#doInitialize

Returns:

A promise to be resolved once the widget has
initialized

Type: Promise

isDesignTime()

Returns true if the Widget is in a graphic design editor.

Returns:

Type: Boolean

isDestroyed()

Return true if this Widget has already been destroyed. After destruction,
initialize() will always reject: the widget cannot be reused.

Returns:

Type: Boolean

isEnabled()

Returns this widget's enabled state.

See:

module:bajaux/Widget#setEnabled

Returns:

Type: Boolean

isInitialized()

Return true if this Widget is initialized.

Returns:

Type: Boolean

isLoading()

Check if this widget is currently in the process of loading. This will
return true immediately after load is called, and return false
after the load promise resolves.

Returns:

Type: Boolean

isModified()

Returns this widget's modified state.

Returns:

Type: Boolean

isReadonly()

Returns this widget's readonly state.

See:

module:bajaux/Widget#setReadonly

Returns:

Type: Boolean

jq()

Returns the jQuery DOM element in which this widget has been initialized.
If initialize() has not yet been called, then this will return null.

Returns:

the DOM element in which this widget has been
initialized, or null if not yet initialized.

Type: JQuery | null

layout( [params])

A widget may need to do its own layout calculation. It might need
to statically position elements, or show/hide them based
on the shape of its container.

This function gives a widget an opportunity to do that. It's called once
the Widget has been initialized and once the form factor has changed.
Also it may be called when the widget's container changes shape
or size, or is shown/hidden.

This method should not typically be overridden. Override
doLayout() instead.

Parameters:

Name	Type	Argument	Description
`params`	*	<optional>	as of Niagara 4.10, any parameters passed to `layout()` will also be passed to `doLayout()`.

Returns:

A promise that's resolved once the layout has
completed.

Type: Promise

load(value [, params])

Updates the widget's HTML with the given value. An widget for editing a
string, for example, might load the string into a text input. A view for
editing a DynamicEnum might programmatically set a <select>
dropdown's value.

load() may not be called until initialize() has completed its work.
If initialize() is not finished, load() will reject.

After load() completes its work, the value loaded will be accessible
via this.value().

load() delegates the work of loading the HTML values to doLoad().
Subclasses will typically not override load, but more commonly will
override doLoad.

After load() completes, a bajaux:load or bajaux:loadfail event will
be triggered, as appropriate. Will also emit a loaded tinyevent.

While this method is performing its work, this.isLoading() will return
true.

Parameters:

Name	Type	Argument	Description
`value`	*		The value to be loaded
`params`	Object	<optional>	additional parameters to be passed to `doLoad()`

See:

Returns:

A promise to be resolved with the loaded value after
the widget has been loaded, or rejected if the widget fails to load the
value.

Type: Promise

properties()

Return the Properties for a widget.

Returns:

The Properties for a widget.

Type: module:bajaux/Properties

read()

Read the current representation of the widget. For instance, if the widget
is made up from two text input boxes, this might resolve an object with
two strings from those text boxes.

Note the word "representation" - this function does not necessarily
return the widget's actual value, but might assemble a different
object, or array, or number, based on current user-entered values.

read will not typically be overridden.
doRead() should be overridden instead.

See:

module:bajaux/Widget#doRead

Returns:

A promise that will be resolved with a value read from
the widget as specified by doRead, or rejected if the read fails.

Type: Promise

requestFocus()

Attempts to place the cursor focus on this editor. For instance, if
showing a simple string editor in a dialog, it should request focus so
that the user can simply begin typing without having to move the mouse
over to it and click.

Override this as necessary; by default, will place focus on the first
input or textarea element in this editor's element.

Since:

Niagara 4.10

resolve(data [, resolveParams])

Resolve a value from some data. Please note, this will not load the value
but will resolve some data that could then be loaded by the widget.

By default, this will treat the data as an ORD so it can be resolved via
BajaScript.

Parameters:

Name	Type	Argument	Description
`data`	* \| String \| baja.Ord		Specifies some data used to resolve a load value so `load(value)` can be called on the widget.
`resolveParams`	Object	<optional>	An Object Literal used for ORD resolution. This parameter is designed to be used internally by bajaux and shouldn't be used by developers.

Returns:

a promise to be resolved with the value resolved from
the given data object

Type: Promise

save( [params])

Saves any outstanding user-entered changes to this widget. Triggers a
bajaux:save or bajaux:savefail event, as appropriate.

In order to save the widget, its current value will be validated using
validate(), then the validated value will be passed to doSave().

This method will not typically be overridden.
doSave() should be overridden instead.

Parameters:

Name	Type	Argument	Description
`params`	Object	<optional>	Additional parameters to be passed to `doSave()`

See:

Returns:

A promise to be resolved once the widget has been saved,
or rejected if the save fails.

Type: Promise

setCommandGroup(commandGroup)

Set this widget's command group. Triggers a bajaux:changecommandgroup
event.

Parameters:

Name	Type	Description
`commandGroup`	module:bajaux/commands/CommandGroup

setEnabled(enabled)

Set this widget's enabled state.

Setting of the internal flag will be synchronous, so isEnabled will
return the expected value immediately after calling this function. However,
the actual work of updating the DOM cannot be performed until after the
widget has finished initializing, so this method will return a promise.

This method will not typically be overridden. doEnabled() should be
overridden instead.

Parameters:

Name	Type	Description
`enabled`	Boolean	the new enabled state

See:

module:bajaux/Widget#isEnabled

Returns:

A promise to resolve immediately if initialize has
not yet been called, that will resolve once the work of initialize
followed by doEnabled have both been completed. It will reject if
initialize or doEnabled fail.

Type: Promise

setModified(modified)

Sets this widget's modified or "dirty" status, to indicate that the user
has made changes to this widget that may need to be saved.

The modification status will only be set if the widget is initialized
and the widget is not loading a new value.

Triggers bajaux:modify or bajaux:unmodify depending on the input value.
Any arguments passed to this function after the first will be passed
through to the triggered event.

This method should not typically be overridden.
doModified() should be overridden
instead.

Parameters:

Name	Type	Description
`modified`	Boolean \| *	(a non-Boolean will be checked for truthiness)

See:

module:bajaux/Widget#doModified

Example

Say I have collection of nested widgets in my DOM element. Whenever one of those widgets is modified, I want to mark myself modified but also provide the originally modified editor. For example, when a Property Sheet is modified, I want to know which row caused the modification.

var that = this;
  dom.on(events.MODIFY_EVENT, function (e, modifiedEd) {
    that.setModified(true, modifiedEd);
    return false;
  });

setReadonly(readonly)

Set this widget's readonly state.

Setting of the internal flag will be synchronous, so isReadonly will
return the expected value immediately after calling this function. However,
the actual work of updating the DOM cannot be performed until after the
widget has finished initializing, so this method will return a promise.

This method will not typically be overridden. doReadonly() should be
overridden instead.

Parameters:

Name	Type	Description
`readonly`	Boolean	the new readonly state.

See:

module:bajaux/Widget#isReadonly

Returns:

A promise to resolve immediately if initialize has
not yet been called, that will resolve once the work of initialize
followed by doReadonly have both been completed. It will reject if
initialize or doReadonly fail.

Type: Promise

toDescription()

Access the widget's icon asynchronously.

By default this will attempt to access the widget's icon from
the originating Lexicon. The Lexicon key should be in the format of
keyName.description. If an entry can't be found then a blank string
will be used.

Returns:

A promise to be resolved with the widget's description

Type: Promise

toDisplayName()

Access the widget's display name asynchronously.

By default, this will attempt to access the widget's display name from
the originating Lexicon. The Lexicon key should be in the format of
keyName.displayName. If an entry can't be found then the Type's
name will be used.

Returns:

A promise to be resolved with the widget's display name

Type: Promise

toIcon()

Access the widget's icon asynchronously.

By default, this will attempt to access the widget's description from
the originating Lexicon. The Lexicon key should be in the format of
keyName.icon. If an entry can't be found then a blank String will be
returned.

Returns:

A promise to be resolved with the widget's icon URI.

Type: Promise

trigger()

Trigger a widget event. By default this fires a DOM event on the associated
widget's DOM element.

validate()

Read the current value from the widget and validate it.

See:

module:bajaux/Validators#validate

Returns:

A promise to be resolved with the value read from the
widget and passed through all validators, or rejected if the value could
not be read or validated.

Type: Promise

validators()

Return the widget's Validators.

See:

module:bajaux/Validators

Returns:

Type: Validators

value()

Returns the widget's current loaded value. This the value that was last
loaded via load(). To read a widget's current representation, reflecting
any user-entered changes, call read(). If no value has been loaded yet,
null is returned.

See:

Returns:

the loaded value, or null if a value hasn't been
loaded yet.

Type: * | null

Module: bajaux/Widget

new (require("bajaux/Widget"))( [params])

Parameters:

Properties

Examples

Requires

Members

<static> css

Properties:

<static> formFactor

Properties:

Methods

<static> in(el)

Parameters:

Returns:

applyParams( [params])

Parameters:

Properties

Returns:

changed(name, value)

Parameters:

Returns:

cleanupDom()

destroy()

Returns:

doChanged(name, value)

Parameters:

Returns:

doDestroy( [params])

Parameters:

Returns:

doEnabled(enabled)

Parameters:

Returns:

doInitialize(element [, params])

Parameters:

Returns:

doLayout( [params])

Parameters:

Returns:

doLoad(value [, params])

Parameters:

Returns:

doModified(modified)

Parameters:

doRead()

Returns:

doReadonly(readonly)

Parameters:

Returns:

doSave(validValue [, params])

Parameters:

Returns:

generateId()

Returns:

getChildWidgets( [params])

Parameters:

Properties

Returns:

Examples

getCommandGroup()

Returns:

getFormFactor()

Returns:

hasMixIn(mixin)

Parameters:

Returns:

initialize(dom [, params] [, layoutParams])

Parameters:

Returns:

isDesignTime()

Returns:

isDestroyed()

Returns:

isEnabled()

Returns:

isInitialized()

Returns:

isLoading()

Returns: