synthcomboboxui.java

Mobile 应用程序使用 Java Micro Edition (Java ME) 平台

    
    /**
     * From BasicComboBoxRenderer v 1.18.
     * 
     * Be aware that SynthFileChooserUIImpl relies on the fact that the default
     * renderer installed on a Synth combo box is a JLabel. If this is changed,
     * then an assert will fail in SynthFileChooserUIImpl
     */
    private class SynthComboBoxRenderer extends JLabel implements ListCellRenderer, UIResource {
        public SynthComboBoxRenderer() {
            super();
            setName("ComboBox.renderer");
            setText(" ");
        }

        @Override
        public Component getListCellRendererComponent(JList list, Object value,
                         int index, boolean isSelected, boolean cellHasFocus) {
            setName("ComboBox.listRenderer");
            SynthLookAndFeel.resetSelectedUI();
            if (isSelected) {
                setBackground(list.getSelectionBackground());
                setForeground(list.getSelectionForeground());
                if (!useListColors) {
                    SynthLookAndFeel.setSelectedUI(
                         (SynthLabelUI)SynthLookAndFeel.getUIOfType(getUI(),
                         SynthLabelUI.class), isSelected, cellHasFocus,
                         list.isEnabled(), false);
                }
            } else {
                setBackground(list.getBackground());
                setForeground(list.getForeground());
            }

            setFont(list.getFont());

            if (value instanceof Icon) {
                setIcon((Icon)value);
                setText("");
            } else {
                String text = (value == null) ? " " : value.toString();

                if ("".equals(text)) {
                    text = " ";
                }
                setText(text);
            }

            // The renderer component should inherit the enabled and
            // orientation state of its parent combobox.  This is
            // especially needed for GTK comboboxes, where the
            // ListCellRenderer's state determines the visual state
            // of the combobox.
            if (comboBox != null){
                setEnabled(comboBox.isEnabled());
                setComponentOrientation(comboBox.getComponentOrientation());
            }

            return this;
        }

        @Override
        public void paint(Graphics g) {
            super.paint(g);
            SynthLookAndFeel.resetSelectedUI();
        }
    }


    /**
     * From BasicCombBoxEditor v 1.24.
     */
    private static class SynthComboBoxEditor implements
                              ComboBoxEditor, UIResource {
        protected JTextField editor;
        private Object oldValue;

        public SynthComboBoxEditor() {
            editor = new JTextField("",9);
            editor.setName("ComboBox.textField");
        }

        @Override
        public Component getEditorComponent() {
            return editor;
        }

        /** 
         * Sets the item that should be edited. 
         *
         * @param anObject the displayed value of the editor
         */
        @Override
        public void setItem(Object anObject) {
            String text;

            if ( anObject != null )  {
                text = anObject.toString();
                oldValue = anObject;
            } else {
                text = "";
            }
            // workaround for 4530952
            if (!text.equals(editor.getText())) {
                editor.setText(text);
            }
        }

        @Override
        public Object getItem() {
            Object newValue = editor.getText();
        
            if (oldValue != null && !(oldValue instanceof String))  {
                // The original value is not a string. Should return the value in it's
                // original type.
                if (newValue.equals(oldValue.toString())) {
                    return oldValue;
                } else {
                    // Must take the value from the editor and get the value and cast it to the new type.
                    Class cls = oldValue.getClass();
                    try {
                        Method method = cls.getMethod("valueOf", new Class[]{String.class});
                        newValue = method.invoke(oldValue, new Object[] { editor.getText()});
                    } catch (Exception ex) {
                        // Fail silently and return the newValue (a String object)
                    }
                }
            }
            return newValue;
        }

        @Override
        public void selectAll() {
            editor.selectAll();
            editor.requestFocus();
        }

        @Override
        public void addActionListener(ActionListener l) {
            editor.addActionListener(l);
        }

        @Override
        public void removeActionListener(ActionListener l) {
            editor.removeActionListener(l);
        }
    }
    
    /**
     * Handles all the logic for treating the combo as a button when it is
     * not editable, and when shouldActLikeButton() is true. This class is a
     * special ButtonModel, and installed on the arrowButton when appropriate.
     * It also is installed as a mouse listener and mouse motion listener on
     * the combo box. In this way, the state between the button and combo
     * are in sync. Whenever one is "over" both are. Whenever one is pressed,
     * both are.
     */
    private final class ButtonHandler extends DefaultButtonModel
            implements MouseListener, PopupMenuListener {
        /**
         * Indicates that the mouse is over the combo or the arrow button.
         * This field only has meaning if buttonWhenNotEnabled is true.
         */
        private boolean over;
        /**
         * Indicates that the combo or arrow button has been pressed. This
         * field only has meaning if buttonWhenNotEnabled is true.
         */
        private boolean pressed;

        //------------------------------------------------------------------
        // State Methods
        //------------------------------------------------------------------
        
        /**
         * <p>Updates the internal "pressed" state. If shouldActLikeButton()
         * is true, and if this method call will change the internal state,
         * then the combo and button will be repainted.</p>
         * 
         * <p>Note that this method is called either when a press event
         * occurs on the combo box, or on the arrow button.</p>
         */
        private void updatePressed(boolean p) {
            this.pressed = p && isEnabled();
            if (shouldActLikeButton()) {
                comboBox.repaint();
            }
        }
        
        /**
         * <p>Updates the internal "over" state. If shouldActLikeButton()
         * is true, and if this method call will change the internal state,
         * then the combo and button will be repainted.</p>
         * 
         * <p>Note that this method is called either when a mouseover/mouseoff event
         * occurs on the combo box, or on the arrow button.</p>
         */
        private void updateOver(boolean o) {
            boolean old = isRollover();
            this.over = o && isEnabled();
            boolean newo = isRollover();
            if (shouldActLikeButton() && old != newo) {
                comboBox.repaint();
            }
        }
        
        //------------------------------------------------------------------
        // DefaultButtonModel Methods
        //------------------------------------------------------------------
        
        /**
         * {@inheritDoc}
         * 
         * Ensures that isPressed() will return true if the combo is pressed,
         * or the arrowButton is pressed, <em>or</em> if the combo popup is
         * visible. This is the case because a combo box looks pressed when
         * the popup is visible, and so should the arrow button.
         */
        @Override
        public boolean isPressed() {
            boolean b = shouldActLikeButton() ? pressed : super.isPressed();
            return b || (pressedWhenPopupVisible && comboBox.isPopupVisible());
        }

        /**
         * {@inheritDoc}
         * 
         * Ensures that the armed state is in sync with the pressed state
         * if shouldActLikeButton is true. Without this method, the arrow
         * button will not look pressed when the popup is open, regardless
         * of the result of isPressed() alone.
         */
        @Override
        public boolean isArmed() {
            boolean b = shouldActLikeButton() 
                    || (pressedWhenPopupVisible && comboBox.isPopupVisible());
            return b ? isPressed() : super.isArmed();
        }

        /**
         * {@inheritDoc}
         * 
         * Ensures that isRollover() will return true if the combo is
         * rolled over, or the arrowButton is rolled over.
         */
        @Override
        public boolean isRollover() {
            return shouldActLikeButton() ? over : super.isRollover();
        }
        
        /**
         * {@inheritDoc}
         * 
         * Forwards pressed states to the internal "pressed" field
         */
        @Override
        public void setPressed(boolean b) {
            super.setPressed(b);
            updatePressed(b);
        }   

        /**
         * {@inheritDoc}
         * 
         * Forwards rollover states to the internal "over" field
         */
        @Override
        public void setRollover(boolean b) {
            super.setRollover(b);
            updateOver(b);
        }
        
        //------------------------------------------------------------------
        // MouseListener/MouseMotionListener Methods
        //------------------------------------------------------------------
        
        @Override
        public void mouseEntered(MouseEvent mouseEvent) {
            updateOver(true);
        }
        
        @Override
        public void mouseExited(MouseEvent mouseEvent) {
            updateOver(false);
        }
        
        @Override
        public void mousePressed(MouseEvent mouseEvent) {
            updatePressed(true);
        }
        
        @Override
        public void mouseReleased(MouseEvent mouseEvent) {
            updatePressed(false);
        }
        
        @Override
        public void mouseClicked(MouseEvent e) {}

        //------------------------------------------------------------------
        // PopupMenuListener Methods
        //------------------------------------------------------------------
        
        /**
         * @inheritDoc
         * 
         * Ensures that the combo box is repainted when the popup is closed.
         * This avoids a bug where clicking off the combo wasn't causing a repaint,
         * and thus the combo box still looked pressed even when it was not.
         * 
         * This bug was only noticed when acting as a button, but may be generally
         * present. If so, remove the if() block
         */
        @Override
        public void popupMenuCanceled(PopupMenuEvent e) {
            if (shouldActLikeButton() || pressedWhenPopupVisible) {
                comboBox.repaint();
            }
        }

        @Override
        public void popupMenuWillBecomeVisible(PopupMenuEvent e) {}
        @Override
        public void popupMenuWillBecomeInvisible(PopupMenuEvent e) {}
    }

    /**
     * Handler for repainting combo when editor component gains/looses focus
     */
    private static class EditorFocusHandler implements FocusListener,
            PropertyChangeListener {
        private JComboBox comboBox;
        private ComboBoxEditor editor = null;
        private Component editorComponent = null;

        private EditorFocusHandler(JComboBox comboBox) {
            this.comboBox = comboBox;
            editor = comboBox.getEditor();
            if (editor != null){
                editorComponent = editor.getEditorComponent();
                if (editorComponent != null){
                    editorComponent.addFocusListener(this);
                }
            }
            comboBox.addPropertyChangeListener("editor",this);
        }

        public void unregister(){
            comboBox.removePropertyChangeListener(this);
            if (editorComponent!=null){
                editorComponent.removeFocusListener(this);
            }
        }

        /** Invoked when a component gains the keyboard focus. */
        public void focusGained(FocusEvent e) {
            // repaint whole combo on focus gain
            comboBox.repaint();
        }

        /** Invoked when a component loses the keyboard focus. */
        public void focusLost(FocusEvent e) {
            // repaint whole combo on focus loss
            comboBox.repaint();
        }

        /**
         * Called when the combos editor changes
         *
         * @param evt A PropertyChangeEvent object describing the event source and
         *            the property that has changed.
         */
        public void propertyChange(PropertyChangeEvent evt) {
            ComboBoxEditor newEditor = comboBox.getEditor();
            if (editor != newEditor){
                if (editorComponent!=null){
                    editorComponent.removeFocusListener(this);
                }
                editor = newEditor;
                if (editor != null){
                    editorComponent = editor.getEditorComponent();
                    if (editorComponent != null){
                        editorComponent.addFocusListener(this);
                    }
                }
            }
        }
    }
}