How to make fxml property "text : " in JavaFX custom control? - javafx

Question

I've developing JavaFX custom button. Like this.
public class MyButton extends Control{
private static final String DEFAULT_STYLE_CLASS = "satrec-button";
private Button button;
public MyButton(){
getStyleClass().setAll(DEFAULT_STYLE_CLASS);
}
#Override
public String getUserAgentStylesheet(){
return "sample/css/button.css";
}
public void setButton(Button button){
this.button = button;
}
public void setText(String text){
this.button.setText(text);
}
}
I want to use this control in FXML. But original button and label can set text to use " test : " Like this
<Button text="Search" textFill="white" prefWidth="130" GridPane.columnIndex="4" GridPane.rowIndex="1" styleClass="control" fx:id="search_btn" />
But MyControl can not use this function. I looked up Labeled class. I know text is a StringProperty.
But I don't know what is this, and how can I use. How do I do?? Please, help me.

Answer 1

The default interpretation of an attribute or child property element of an instance FXML element is that it maps to a JavaFX property in the instance. (Essentially it is relying on the control using the JavaFX properties pattern.)
In other words, in your FXML snippet:
<MyButton text="Search" ... />
or, equivalently,
<MyButton>
<text>
<String fx:value="Search" />
</text>
</MyButton>
<MyButton> is an instance element, and it causes the FXMLLoader to create a new instance of the MyButton class, calling the default constructor by default. In either version, text (an attribute in the first version, a property element in the second) is going to cause the FXMLLoader to look for a textProperty() method, returning a WritableValue instance (for example a StringProperty). Assuming it finds one, it will call setValue(...) on that WritableValue, passing in the string "Search". (See the FXML documentation for a full description of all this terminology.)
So you just need your MyButton class to define an appropriate textProperty() method. Since you want this to be the text of the included button, you can just delegate to that button's method:
public class MyButton extends Control{
private static final String DEFAULT_STYLE_CLASS = "satrec-button";
private Button button;
public MyButton(){
getStyleClass().setAll(DEFAULT_STYLE_CLASS);
}
#Override
public String getUserAgentStylesheet(){
return "sample/css/button.css";
}
public void setButton(Button button){
this.button = button;
}
public StringProperty textProperty() {
if (button == null) { // might be better to write the class so that this is never true?
button = new Button();
}
return button.textProperty();
}
public final void setText(String text) {
textProperty().set(text);
}
public final String getText() {
return textProperty().get();
}
}

Answer 2

You can use the NamedArg Annotation:
public MyButton(#NamedArg("text") String text) {
this();
this.setText(text);
}
otherwise the fxml doesn't know which constructor argument you mean.
Now can use your Button in your fxml as you asked:
<MyButton text="Search" ....