Widgets with Arguments
Widgets do not need to have arguments or parameters, but most Widgets are best designed with some customization available to the user.
Let us add a few arguments to our Simple Widget.
Add an Simple Text Argument
Our starting point looks like this.
We want to give the user an option to change the target of the link. To start we will add the urlTarget
argument to the renderIt()
and then use that argument in our link.
When the user tries to use the widget now, they'll see this added to the Widget selector.
Adding more User Friendly Options to Arguments
You will see the argument name urlTarget
shown, with the type (any)
. We can add some more options to the arguments to make it more user friendly, including:
Label
Required
Hint
Type
Default
Options
OptionsUDF
MultiOptions
MultiOptionsUDF
These are all added via the JavaDoc syntax for the RenderIt() function. Below is an example of the label being used.
Argument Label
The Label is used when you want to have a more meaningful label for the form field than the name of the argument itself. In our example, by default, the label is urlTarget
, but we can change it to something like This is my Label
The Widget Form now shows this label instead of the Argument name
Required Argument
Required does what it says, it makes a field a required field. This will show a label and add the necessary validation.
To make a field required, add Javadoc Meta comment @urlTarget.required
to the function meta.
Argument Hint
A label goes a long way in helping the user understand the purpose of a field, but you can also use Hints to make this crystal clear.
To add a field hint, add Javadoc Meta comment @urlTarget.hint
to the function meta.
Argument Type
Argument Type is very important. By default, all arguments are considered strings, and are shown as a Text Input. The type tells the Widget form builder how to display the argument field. The logic is processed in this order.
Boolean - as a yes / no select drop down
Numeric / String with Options - Select drop down with items from the options list.
Numeric / String with OptionsUDF - Select drop down with items from the options UDF
Numeric / String with MultiOptions - Multiple Select drop down with items from the options list.
Numeric / String with MultiOptionsUDF - Multiple Select drop down with items from the options UDF
Numeric / String - Text Input box
Argument Type can be defined by the Function definition, or with the Meta Data. Below you can see these argument types being set inside the function itself.
You can also use the Meta Data approach that most of the argument options require.
Default Value
You can set a default Value for the field.
To add a default value for an argument, add Javadoc Meta comment @urlTarget.default _blank
to the function meta.
Options for Arguments
Using Labels, Hints and Required fields helps the user, but in some cases its best if you can give your users a set list of options to pick from. This will provide the user a select drop down box, instead of a text box. This ensures there are no typos.
To add options for an argument, add Javadoc Meta comment @urlTarget.options _self,_blank,_top,_parent
to the function meta.
As you can see, the Default value even works with the options drop down, so you can have the default, pre-selected.
Options for Arguments via UDF
Option lists work great for some use cases, but sometimes you might need some dynamic information. This allows you to write a function, and the Widget form builder calls that function for you to load the options. To use an optionsUDF instead of options you need to do 2 things.
1- To add options for an argument via UDF, add Javadoc Meta comment @urlTarget.optionsUDF getTargetTypes
to the function meta. The function should be the name without the parenthesis.
2- Add the new function. The new function can be named anything ( other than RenderIt - the default function for a widget ). The function must return an array of elements that can be converted to a string. Here is the UDF function that matches the previous list of options, but this time, we added one, to be sure it is from the UDF.
Reload and test the widget, we see the list of Target Types.
You might see a side effect of adding the function. Now you will see another option, Public Methods
with a list of public functions in ths CFC. Widgets are required to implement the default RenderIt()
function, but the Widget can actually have several methods.
To hide this function ( since this is outputting an array, not a string ), you cannot use a private function ( otherwise the UDF cannot be called by the Form Builder ), you need to add some meta data to ignore the function.
or you could use the inline meta
With either of these two options, you will see the list of Options provided by the UDF, but you will not see the Public Methods
option, as there is only 1 public rendering function.
MultiOptions - Multiple Choice Options
Using Labels, Hints and Required fields helps the user, but in some cases its best if you can give your users a set list of options to pick from, especially if they user could/should pick one or more options. This will provide the user a multi select drop down box, instead of a text box. This ensures there are no typos.
To add options for an argument, add Javadoc Meta comment @urlTarget.multioptions _self,_blank,_top,_parent
to the function meta.
MultiOptionsUDF - Multiple Choice Options via UDF
MultiOptionsUDF works the same as OptionsUDF except the user can select none, one or more of the options.
Add the meta to the RenderIt() function
Add the UDF ( include the cbignore meta data so the Widget Form builder ignores the function )
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