I've written a custom widget with its own set of styles. These styles are defined in a little resource interface contained in the widget, and applied in the constructor of the widget.
I'd like to use the widget in a uibinder xml file, and apply additional styles there. Unfortunately, setting the styleName attribute seems to remove the styles applied in the constructor, and indeed the setStyleName javadoc indicates that it clears other style names.
What's the best solution here? I could override setStyleName, but that takes away options later. Is there a way to call addStyleName instead of setStyleName from the ui.xml file?
Did you try addStyleNames in your ui binder file?
Related
How do I override a widget in order to provide some custom modifications to one of its property.
For example: Let's say I want to create my own Text widget which will convert whole text to uppercase. I'll do something like:
class MyOwnText extends Text {
MyOwnText(String data) : super(data.toUpperCase());
}
But with this approach, I can't use other properties of Text in my own widget, style, for example. For that, I'll have to add style property in my class constructor like this:
MyOwnText(String data, {TextStyle style}) : super(data.toUpperCase(), style: style);
But Text has got around 12-13 properties, and just to override one, I need to define all of those properties and then their assertion. I'm sure I may not be doing something right. Can anyone please help?
Note: Neither I want to use extension methods nor some client side code. MyOwnText should be a Text.
I get what you wanted to achieve, but I do not recommend to do this.
Why?? - Because most of the class has private variable and they have their separate getter and setter which are expose to the outer front of the class.
Again, If you wanted to for design and func. then you should not extend the widget. Instead you can directly use those in your build method
Why?? - You can't inherit more than one class(Mixin is other way around here)
So ultimately you need to assign properties directly or you could use spread operator
I am creating a custom widget, say "CustomWid" in UiBinder.
And in CustomWid.java file I am writing two constructors
one with zero args like
CustomWid(){....}
another with some args like
CustomWid(String a,String b){......}
So,Now I am using my custom widget in another .ui.xml file,in that .ui.xml file
it is working fine when we give
<my:CustomWid/> alone,
and also fine when we give like
<my:CustomWid a="srt1" b="str2"/> alone
But "MY PROBLEM" is whenever I am trying to give both the tags in the one .ui.xml as
<my:CustomWid/>
<my:CustomWid a="str1" b="str2"/>
Now it is throwing error when i am using both types of tags in a single .ui.xml
I mean How to use my custom widget tag like a prdefined tag?
I am using #uiConstructor, but it showing error
Please developers... I need answer as early as possible
UiBinder will only ever use a single constructor for a given widget: either its zero-arg constructor, or a #UiConstructor (I'm surprised that you say it works when using either one or the other call but not both: one should fail in every case, and one should succeed in every case; if you haven't annotated a constructor with #UiConstructor, then <my:CustomWid/> should always work and <my:CustomWid a="str1" b="str2"/> should always fail)
There are two solutions here:
use setters for the a and b attributes (void setA(String a) and void setB(String b))), and possibly check later (say, in onLoad or onAttach) that you have either none or both of A and B, but not one without the other (if that's your rule).
use #UiField(provided = true) when you need to use the other constructor (if you choose to have UiBinder use the zero-arg constructor –i.e. no #UiConstructor–, then that means you'll have to move the a="str1" b="str2" from the XML to the Java code: #UiField(provided = true) CustomWid myCustomWid = new CustomWid("str1", "str2")).
The first option has my preference.
It Will not show any errors...'
#UiConstructor
public Component(String displayText,String heading)
{
initWidget(uiBinder.createAndBindUi(this));
this.displayText.setText(displayText);
this.heading.setText(heading);
}`
now use another constructor with default parameters also it will work
public Component()
{
initWidget(uiBinder.createAndBindUi(this));
}
now if you add with xml parameters component and without parameters also works in the same page.
If you are defining an Editor in GWT using the UiBinder, then you can specify the path to a property value using the #Path annotation.
If you are defining an Editor without using the UiBinder (i.e programmatically), how can you specify the path to an editable attribute without using the annotation?
You can use the same #Path annotation on the declared fields.
It is not bound to UiBinder.
You can bind properties to fields in 2 ways -
1) Declare the field with the same name as the property.
2) #Path annotation, in case, if the field and the property are declared with different names.
If you don't want to bind any property to the field, declare that field with #Ignore annotation.
These annotations are all used by Editor Framework's Code generator to generate some supporting java classes.
So, At Runtime you can not change the Path of the editors programmatically.
If you define your UI programmatically, you can still use #Path (or just name the field to match the property) on a field in your widget class. Not using UiBinder doesn't mean you can't use the Editor Framework.
That said, paths cannot be defined programmatically, no matter how you build the ui. The Editor Driver generating code requires that it can see which properties will be used so it only generates the necessary code to wire properties into editors.
Editor and UiBinder are totally distinct features - it just so happens that both can wire into fields in your class. UiBinder doesn't care about #Path annotations any more than Editors care about #UiField
I would like to add widgets (checkboxes) in an already defined form (with configure method).
I can't add them in the definition of the form because the number of widgets varies (according to the object).
I see two ways of doing it :
Either pass a variable into the configure method of the form or maybe use embedded forms.
But which one is the right way ? Is there another solution ?
Thank you
The right way is to pass the object right into the options. In the form you can use the $this->getOption method to retrieve the passed options.
I Agree with Don Pinkster on passing option and use it to configure form in configure() method.
But if need it or can't get the value when instanciating the class, you can use from anywhere :
$form->getWidgetSchema()->offsetSet($name, $widget);
$form->getValidatorSchema()->offsetSet($name, $validator)
The fact you use embedded forms or widget will not change that much, as you can do this after the form is initially configured :
$form->embedForm($name, $form2);
For just one checkbox I don't see advantages in using embedded form.
In both cases, I suggest you do this in a public method from your form's class, to avoid exploding the form configuration in the action class or elsewhere.
Regards,
This may sound very weird, but let's start with an example:
<my:MagicWidget ui:field="someFieldName" fieldName="someFieldName"/>
It's pretty much asured that we'll always want to have the same value in ui:field and in fieldName. Clearly there is some duplucation in this code, I'd like to avoid it and make the fieldName optional.
So, this is what I have in the widget's code:
#UiConstructor
public MagicWidget(String fieldName) {
this.fieldName = fieldName;
}
But I'd like, if possible to allow this constructor to be optional, and provide an default constructor that would "by magic" find out it's ui:field value:
#UiConstructor
public MagicWidget() {
this.fieldName = /*some magic to get ui:field's value*/;
}
I was wondering if there is a way to get the value of "ui:field" inside my MagickWidget? (The widget extends Composite). I fear this might not be possible, because most of the time it's not so useful, but if anyone has an idea - feel free to share!
PS: I'm using GWT 2.1.0.RC1.
As you may know, the ui:field is there so you can interact with a UI Object in Java code after you've declared it with UiBinder. So, for example, if you add a MagicWidget in a UiBinder template, you can write
#UiField MagicWidget someWidget
in order to be able to interact with it programatically. Having your magic widget aware of the name of the reference that is pointing to it might not be all that helpful (or possible), as you can pass the reference to that specific MagicWidget back and forth between different parts of your application. A single MagicWidget could easily have several references with different names pointing at is simultaneously. That's why it's difficult to pick it out "by magic" at runtime. I realize this isn't much of an issue if you only want this value when the object is constructed, but keep in mind that you're not required to include a ui:field when you add a widget using UiBinder.
Why is it important that the Widget know its field name? Knowing that might make it easier to provide suggestions about other ways to accomplish what you are looking to do.