javafx.scene.control.ComboBoxBase Maven / Gradle / Ivy
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package javafx.scene.control;
import javafx.collections.MapChangeListener;
import javafx.css.PseudoClass;
import javafx.beans.property.*;
import javafx.event.ActionEvent;
import javafx.event.Event;
import javafx.event.EventHandler;
import javafx.event.EventType;
import javafx.scene.AccessibleAction;
import javafx.scene.AccessibleAttribute;
/**
* Abstract base class for ComboBox-like controls. A ComboBox typically has
* a button that, when clicked, will pop up some means of allowing a user
* to select one or more values (depending on the implementation). This base
* class makes no assumptions about what happens when the {@link #show()} and
* {@link #hide()} methods are called, however commonly this results in either
* a popup or dialog appearing that allows for the user to provide the
* required information.
*
* A ComboBox has a {@link #valueProperty() value} property that represents
* the current user input. This may be based on a selection from a drop-down list,
* or it may be from user input when the ComboBox is
* {@link #editableProperty() editable}.
*
*
An {@link #editableProperty() editable} ComboBox is one which provides some
* means for an end-user to provide input for values that are not otherwise
* options available to them. For example, in the {@link ComboBox} implementation,
* an editable ComboBox provides a {@link TextField} that may be typed into.
* As mentioned above, when the user commits textual input into the textfield
* (commonly by pressing the Enter keyboard key), the
* {@link #valueProperty() value} property will be updated.
*
*
The purpose of the separation between this class and, say, {@link ComboBox}
* is to allow for ComboBox-like controls that do not necessarily pop up a list
* of items. Examples of other implementations include color pickers, calendar
* pickers, etc. The {@link ComboBox} class provides the default, and most commonly
* expected implementation. Refer to that classes javadoc for more information.
*
* @see ComboBox
* @param The type of the value that has been selected or otherwise
* entered in to this ComboBox.
* @since JavaFX 2.1
*/
public abstract class ComboBoxBase extends Control {
/* *************************************************************************
* *
* Static properties and methods *
* *
**************************************************************************/
/**
* Called prior to the ComboBox showing its popup/display after the user
* has clicked or otherwise interacted with the ComboBox.
* @since JavaFX 2.2
*/
public static final EventType ON_SHOWING =
new EventType<>(Event.ANY, "COMBO_BOX_BASE_ON_SHOWING");
/**
* Called after the ComboBox has shown its popup/display.
* @since JavaFX 2.2
*/
public static final EventType ON_SHOWN =
new EventType<>(Event.ANY, "COMBO_BOX_BASE_ON_SHOWN");
/**
* Called when the ComboBox popup/display will be hidden.
* @since JavaFX 2.2
*/
public static final EventType ON_HIDING =
new EventType<>(Event.ANY, "COMBO_BOX_BASE_ON_HIDING");
/**
* Called when the ComboBox popup/display has been hidden.
* @since JavaFX 2.2
*/
public static final EventType ON_HIDDEN =
new EventType<>(Event.ANY, "COMBO_BOX_BASE_ON_HIDDEN");
/* *************************************************************************
* *
* Constructors *
* *
**************************************************************************/
/**
* Creates a default ComboBoxBase instance.
*/
public ComboBoxBase() {
getStyleClass().add(DEFAULT_STYLE_CLASS);
// Fix for RT-29885
getProperties().addListener((MapChangeListener) change -> {
if (change.wasAdded()) {
if (change.getKey() == "FOCUSED") {
setFocused((Boolean)change.getValueAdded());
getProperties().remove("FOCUSED");
}
}
});
// End of fix for RT-29885
}
/* *************************************************************************
* *
* Properties *
* *
**************************************************************************/
// --- value
/**
* The value of this ComboBox is defined as the selected item if the input
* is not editable, or if it is editable, the most recent user action:
* either the value input by the user, or the last selected item.
* @return the value property
*/
public ObjectProperty valueProperty() { return value; }
private ObjectProperty value = new SimpleObjectProperty<>(this, "value");
public final void setValue(T value) { valueProperty().set(value); }
public final T getValue() { return valueProperty().get(); }
// --- editable
/**
* Specifies whether the ComboBox allows for user input. When editable is
* true, the ComboBox has a text input area that a user may type in to. This
* input is then available via the {@link #valueProperty() value} property.
*
* Note that when the editable property changes, the value property is
* reset, along with any other relevant state.
* @return the editable property
*/
public BooleanProperty editableProperty() { return editable; }
public final void setEditable(boolean value) { editableProperty().set(value); }
public final boolean isEditable() { return editableProperty().get(); }
private BooleanProperty editable = new SimpleBooleanProperty(this, "editable", false) {
@Override protected void invalidated() {
pseudoClassStateChanged(PSEUDO_CLASS_EDITABLE, get());
}
};
// --- showing
/**
* Represents the current state of the ComboBox popup, and whether it is
* currently visible on screen (although it may be hidden behind other windows).
*/
private ReadOnlyBooleanWrapper showing;
public ReadOnlyBooleanProperty showingProperty() { return showingPropertyImpl().getReadOnlyProperty(); }
public final boolean isShowing() { return showingPropertyImpl().get(); }
private void setShowing(boolean value) {
// these events will not fire if the showing property is bound
Event.fireEvent(this, value ? new Event(ComboBoxBase.ON_SHOWING) :
new Event(ComboBoxBase.ON_HIDING));
showingPropertyImpl().set(value);
Event.fireEvent(this, value ? new Event(ComboBoxBase.ON_SHOWN) :
new Event(ComboBoxBase.ON_HIDDEN));
}
private ReadOnlyBooleanWrapper showingPropertyImpl() {
if (showing == null) {
showing = new ReadOnlyBooleanWrapper(false) {
@Override protected void invalidated() {
pseudoClassStateChanged(PSEUDO_CLASS_SHOWING, get());
notifyAccessibleAttributeChanged(AccessibleAttribute.EXPANDED);
}
@Override
public Object getBean() {
return ComboBoxBase.this;
}
@Override
public String getName() {
return "showing";
}
};
}
return showing;
}
// --- prompt text
/**
* The {@code ComboBox} prompt text to display, or {@code null} if no
* prompt text is displayed. Prompt text is not displayed in all circumstances,
* it is dependent upon the subclasses of ComboBoxBase to clarify when
* promptText will be shown. For example, in most cases prompt text will never be
* shown when a combo box is non-editable (that is, prompt text is only shown
* when user input is allowed via text input).
*/
private StringProperty promptText = new SimpleStringProperty(this, "promptText", null) {
@Override protected void invalidated() {
// Strip out newlines
String txt = get();
if (txt != null && txt.contains("\n")) {
txt = txt.replace("\n", "");
set(txt);
}
}
};
public final StringProperty promptTextProperty() { return promptText; }
public final String getPromptText() { return promptText.get(); }
public final void setPromptText(String value) { promptText.set(value); }
// --- armed
/**
* Indicates that the ComboBox has been "armed" such that a mouse release
* will cause the ComboBox {@link #show()} method to be invoked. This is
* subtly different from pressed. Pressed indicates that the mouse has been
* pressed on a Node and has not yet been released. {@code arm} however
* also takes into account whether the mouse is actually over the
* ComboBox and pressed.
* @return the armed property
*/
public BooleanProperty armedProperty() { return armed; }
private final void setArmed(boolean value) { armedProperty().set(value); }
public final boolean isArmed() { return armedProperty().get(); }
private BooleanProperty armed = new SimpleBooleanProperty(this, "armed", false) {
@Override protected void invalidated() {
pseudoClassStateChanged(PSEUDO_CLASS_ARMED, get());
}
};
// --- On Action
/**
* The ComboBox action, which is invoked whenever the ComboBox
* {@link #valueProperty() value} property is changed. This
* may be due to the value property being programmatically changed, when the
* user selects an item in a popup list or dialog, or, in the case of
* {@link #editableProperty() editable} ComboBoxes, it may be when the user
* provides their own input (be that via a {@link TextField} or some other
* input mechanism.
* @return the on action property
*/
public final ObjectProperty> onActionProperty() { return onAction; }
public final void setOnAction(EventHandler value) { onActionProperty().set(value); }
public final EventHandler getOnAction() { return onActionProperty().get(); }
private ObjectProperty> onAction = new ObjectPropertyBase<>() {
@Override protected void invalidated() {
setEventHandler(ActionEvent.ACTION, get());
}
@Override
public Object getBean() {
return ComboBoxBase.this;
}
@Override
public String getName() {
return "onAction";
}
};
// --- On Showing
public final ObjectProperty> onShowingProperty() { return onShowing; }
public final void setOnShowing(EventHandler value) { onShowingProperty().set(value); }
public final EventHandler getOnShowing() { return onShowingProperty().get(); }
/**
* Called just prior to the {@code ComboBoxBase} popup/display being shown.
* @since JavaFX 2.2
*/
private ObjectProperty> onShowing = new ObjectPropertyBase<>() {
@Override protected void invalidated() {
setEventHandler(ON_SHOWING, get());
}
@Override public Object getBean() {
return ComboBoxBase.this;
}
@Override public String getName() {
return "onShowing";
}
};
// -- On Shown
public final ObjectProperty> onShownProperty() { return onShown; }
public final void setOnShown(EventHandler value) { onShownProperty().set(value); }
public final EventHandler getOnShown() { return onShownProperty().get(); }
/**
* Called just after the {@link ComboBoxBase} popup/display is shown.
* @since JavaFX 2.2
*/
private ObjectProperty> onShown = new ObjectPropertyBase<>() {
@Override protected void invalidated() {
setEventHandler(ON_SHOWN, get());
}
@Override public Object getBean() {
return ComboBoxBase.this;
}
@Override public String getName() {
return "onShown";
}
};
// --- On Hiding
public final ObjectProperty> onHidingProperty() { return onHiding; }
public final void setOnHiding(EventHandler value) { onHidingProperty().set(value); }
public final EventHandler getOnHiding() { return onHidingProperty().get(); }
/**
* Called just prior to the {@link ComboBox} popup/display being hidden.
* @since JavaFX 2.2
*/
private ObjectProperty> onHiding = new ObjectPropertyBase<>() {
@Override protected void invalidated() {
setEventHandler(ON_HIDING, get());
}
@Override public Object getBean() {
return ComboBoxBase.this;
}
@Override public String getName() {
return "onHiding";
}
};
// --- On Hidden
public final ObjectProperty> onHiddenProperty() { return onHidden; }
public final void setOnHidden(EventHandler value) { onHiddenProperty().set(value); }
public final EventHandler getOnHidden() { return onHiddenProperty().get(); }
/**
* Called just after the {@link ComboBoxBase} popup/display has been hidden.
* @since JavaFX 2.2
*/
private ObjectProperty> onHidden = new ObjectPropertyBase<>() {
@Override protected void invalidated() {
setEventHandler(ON_HIDDEN, get());
}
@Override public Object getBean() {
return ComboBoxBase.this;
}
@Override public String getName() {
return "onHidden";
}
};
/* *************************************************************************
* *
* Methods *
* *
**************************************************************************/
/**
* Requests that the ComboBox display the popup aspect of the user interface.
* As mentioned in the {@link ComboBoxBase} class javadoc, what is actually
* shown when this method is called is undefined, but commonly it is some
* form of popup or dialog window.
*/
public void show() {
if (!isDisabled()) {
setShowing(true);
}
}
/**
* Closes the popup / dialog that was shown when {@link #show()} was called.
*/
public void hide() {
if (isShowing()) {
setShowing(false);
}
}
/**
* Arms the ComboBox. An armed ComboBox will show a popup list on the next
* expected UI gesture.
*
* Note: This function is intended to be used by experts, primarily
* by those implementing new Skins or Behaviors. It is not common
* for developers or designers to access this function directly.
*/
public void arm() {
if (! armedProperty().isBound()) {
setArmed(true);
}
}
/**
* Disarms the ComboBox. See {@link #arm()}.
*
* Note: This function is intended to be used by experts, primarily
* by those implementing new Skins or Behaviors. It is not common
* for developers or designers to access this function directly.
*/
public void disarm() {
if (! armedProperty().isBound()) {
setArmed(false);
}
}
/* *************************************************************************
* *
* Stylesheet Handling *
* *
**************************************************************************/
private static final String DEFAULT_STYLE_CLASS = "combo-box-base";
private static final PseudoClass PSEUDO_CLASS_EDITABLE =
PseudoClass.getPseudoClass("editable");
private static final PseudoClass PSEUDO_CLASS_SHOWING =
PseudoClass.getPseudoClass("showing");
private static final PseudoClass PSEUDO_CLASS_ARMED =
PseudoClass.getPseudoClass("armed");
/* *************************************************************************
* *
* Accessibility handling *
* *
**************************************************************************/
/** {@inheritDoc} */
@Override
public Object queryAccessibleAttribute(AccessibleAttribute attribute, Object... parameters) {
switch (attribute) {
case EXPANDED: return isShowing();
case EDITABLE: return isEditable();
default: return super.queryAccessibleAttribute(attribute, parameters);
}
}
/** {@inheritDoc} */
@Override
public void executeAccessibleAction(AccessibleAction action, Object... parameters) {
switch (action) {
case EXPAND: show(); break;
case COLLAPSE: hide(); break;
default: super.executeAccessibleAction(action); break;
}
}
}