Styling a Widget
To make your widget look stylish, you need to style it. There are two basic ways to define CSS styles for a component: in the widget sources and in a theme. A default style should be defined in the widget sources, and different themes can then modify the style.
Determining the CSS Class
The CSS class of a widget element is normally defined in the widget class and set with setStyleName(). A widget should set the styles for its sub-elements as it desires.
For example, you could style a composite widget with an overall style and with separate styles for the sub-widgets as follows:
public class MyPickerWidget extends ComplexPanel {
public static final String CLASSNAME = "mypicker";
private final TextBox textBox = new TextBox();
private final PushButton button = new PushButton("...");
public MyPickerWidget() {
setElement(Document.get().createDivElement());
setStylePrimaryName(CLASSNAME);
textBox.setStylePrimaryName(CLASSNAME + "-field");
button.setStylePrimaryName(CLASSNAME + "-button");
add(textBox, getElement());
add(button, getElement());
button.addClickHandler(new ClickHandler() {
public void onClick(ClickEvent event) {
Window.alert("Calendar picker not yet supported!");
}
});
}
}In addition, all Vaadin components get the v-widget class. If it extends an existing Vaadin or GWT widget, it will inherit CSS classes from that as well.
Default Stylesheet
A client-side module, which is normally a widget set, can include stylesheets. They must be placed under the public folder under the folder of the widget set, a described in "Specifying a Stylesheet".
For example, you could style the widget described above as follows:
.mypicker {
white-space: nowrap;
}
.mypicker-button {
display: inline-block;
border: 1px solid black;
padding: 3px;
width: 15px;
text-align: center;
}Notice that some size settings may require more complex handling and calculating the sizes dynamically.