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package javax.swing.plaf.synth;

import javax.swing.*;
import javax.swing.plaf.*;
import javax.swing.plaf.basic.*;
import javax.swing.text.View;
import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Insets;
import java.awt.Graphics;
import java.awt.FontMetrics;
import java.beans.PropertyChangeEvent;


Provides the Synth L&F UI delegate for JLabel. 
Author:Scott Violet
Since:1.7
/**
 * Provides the Synth L&F UI delegate for
 * {@link javax.swing.JLabel}.
 *
 * @author Scott Violet
 * @since 1.7
 */
public class SynthLabelUI extends BasicLabelUI implements SynthUI {
    private SynthStyle style;

    
Returns the LabelUI implementation used for the skins look and feel.

Params:
  • c – component to create UI object for
Returns:the UI object
/**
     * Returns the LabelUI implementation used for the skins look and feel.
     *
     * @param c component to create UI object for
     * @return the UI object
     */
    public static ComponentUI createUI(JComponent c){
        return new SynthLabelUI();
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void installDefaults(JLabel c) {
        updateStyle(c);
    }

    void updateStyle(JLabel c) {
        SynthContext context = getContext(c, ENABLED);
        style = SynthLookAndFeel.updateStyle(context, this);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    protected void uninstallDefaults(JLabel c){
        SynthContext context = getContext(c, ENABLED);

        style.uninstallDefaults(context);
        style = null;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public SynthContext getContext(JComponent c) {
        return getContext(c, getComponentState(c));
    }

    private SynthContext getContext(JComponent c, int state) {
        return SynthContext.getContext(c, style, state);
    }

    private int getComponentState(JComponent c) {
        int state = SynthLookAndFeel.getComponentState(c);
        if (SynthLookAndFeel.getSelectedUI() == this &&
                        state == SynthConstants.ENABLED) {
            state = SynthLookAndFeel.getSelectedUIState() | SynthConstants.ENABLED;
        }
        return state;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public int getBaseline(JComponent c, int width, int height) {
        if (c == null) {
            throw new NullPointerException("Component must be non-null");
        }
        if (width < 0 || height < 0) {
            throw new IllegalArgumentException(
                    "Width and height must be >= 0");
        }
        JLabel label = (JLabel)c;
        String text = label.getText();
        if (text == null || text.isEmpty()) {
            return -1;
        }
        Insets i = label.getInsets();
        Rectangle viewRect = new Rectangle();
        Rectangle textRect = new Rectangle();
        Rectangle iconRect = new Rectangle();
        viewRect.x = i.left;
        viewRect.y = i.top;
        viewRect.width = width - (i.right + viewRect.x);
        viewRect.height = height - (i.bottom + viewRect.y);

        // layout the text and icon
        SynthContext context = getContext(label);
        FontMetrics fm = context.getComponent().getFontMetrics(
            context.getStyle().getFont(context));
        context.getStyle().getGraphicsUtils(context).layoutText(
            context, fm, label.getText(), label.getIcon(),
            label.getHorizontalAlignment(), label.getVerticalAlignment(),
            label.getHorizontalTextPosition(), label.getVerticalTextPosition(),
            viewRect, iconRect, textRect, label.getIconTextGap());
        View view = (View)label.getClientProperty(BasicHTML.propertyKey);
        int baseline;
        if (view != null) {
            baseline = BasicHTML.getHTMLBaseline(view, textRect.width,
                                                 textRect.height);
            if (baseline >= 0) {
                baseline += textRect.y;
            }
        }
        else {
            baseline = textRect.y + fm.getAscent();
        }
        return baseline;
    }

    
Notifies this UI delegate to repaint the specified component. This method paints the component background, then calls the paint(SynthContext, Graphics) method. 
In general, this method does not need to be overridden by subclasses. All Look and Feel rendering code should reside in the paint method. 
Params:
  • g – the Graphics object used for painting
  • c – the component being painted
See Also:
/**
     * Notifies this UI delegate to repaint the specified component.
     * This method paints the component background, then calls
     * the {@link #paint(SynthContext,Graphics)} method.
     *
     * <p>In general, this method does not need to be overridden by subclasses.
     * All Look and Feel rendering code should reside in the {@code paint} method.
     *
     * @param g the {@code Graphics} object used for painting
     * @param c the component being painted
     * @see #paint(SynthContext,Graphics)
     */
    @Override
    public void update(Graphics g, JComponent c) {
        SynthContext context = getContext(c);

        SynthLookAndFeel.update(context, g);
        context.getPainter().paintLabelBackground(context,
                          g, 0, 0, c.getWidth(), c.getHeight());
        paint(context, g);
    }

    
Paints the specified component according to the Look and Feel.

This method is not used by Synth Look and Feel. Painting is handled by the paint(SynthContext, Graphics) method. 
Params:
  • g – the Graphics object used for painting
  • c – the component being painted
See Also:
/**
     * Paints the specified component according to the Look and Feel.
     * <p>This method is not used by Synth Look and Feel.
     * Painting is handled by the {@link #paint(SynthContext,Graphics)} method.
     *
     * @param g the {@code Graphics} object used for painting
     * @param c the component being painted
     * @see #paint(SynthContext,Graphics)
     */
    @Override
    public void paint(Graphics g, JComponent c) {
        SynthContext context = getContext(c);

        paint(context, g);
    }

    
Paints the specified component.

Params:
  • context – context for the component being painted
  • g – the Graphics object used for painting
See Also:
/**
     * Paints the specified component.
     *
     * @param context context for the component being painted
     * @param g the {@code Graphics} object used for painting
     * @see #update(Graphics,JComponent)
     */
    protected void paint(SynthContext context, Graphics g) {
        JLabel label = (JLabel)context.getComponent();
        Icon icon = (label.isEnabled()) ? label.getIcon() :
                                          label.getDisabledIcon();

        g.setColor(context.getStyle().getColor(context,
                                               ColorType.TEXT_FOREGROUND));
        g.setFont(style.getFont(context));
        context.getStyle().getGraphicsUtils(context).paintText(
            context, g, label.getText(), icon,
            label.getHorizontalAlignment(), label.getVerticalAlignment(),
            label.getHorizontalTextPosition(), label.getVerticalTextPosition(),
            label.getIconTextGap(), label.getDisplayedMnemonicIndex(), 0);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void paintBorder(SynthContext context, Graphics g, int x,
                            int y, int w, int h) {
        context.getPainter().paintLabelBorder(context, g, x, y, w, h);
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public Dimension getPreferredSize(JComponent c) {
        JLabel label = (JLabel)c;
        Icon icon = (label.isEnabled()) ? label.getIcon() :
                                          label.getDisabledIcon();
        SynthContext context = getContext(c);
        Dimension size = context.getStyle().getGraphicsUtils(context).
            getPreferredSize(
               context, context.getStyle().getFont(context), label.getText(),
               icon, label.getHorizontalAlignment(),
               label.getVerticalAlignment(), label.getHorizontalTextPosition(),
               label.getVerticalTextPosition(), label.getIconTextGap(),
               label.getDisplayedMnemonicIndex());

        return size;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public Dimension getMinimumSize(JComponent c) {
        JLabel label = (JLabel)c;
        Icon icon = (label.isEnabled()) ? label.getIcon() :
                                          label.getDisabledIcon();
        SynthContext context = getContext(c);
        Dimension size = context.getStyle().getGraphicsUtils(context).
            getMinimumSize(
               context, context.getStyle().getFont(context), label.getText(),
               icon, label.getHorizontalAlignment(),
               label.getVerticalAlignment(), label.getHorizontalTextPosition(),
               label.getVerticalTextPosition(), label.getIconTextGap(),
               label.getDisplayedMnemonicIndex());

        return size;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public Dimension getMaximumSize(JComponent c) {
        JLabel label = (JLabel)c;
        Icon icon = (label.isEnabled()) ? label.getIcon() :
                                          label.getDisabledIcon();
        SynthContext context = getContext(c);
        Dimension size = context.getStyle().getGraphicsUtils(context).
               getMaximumSize(
               context, context.getStyle().getFont(context), label.getText(),
               icon, label.getHorizontalAlignment(),
               label.getVerticalAlignment(), label.getHorizontalTextPosition(),
               label.getVerticalTextPosition(), label.getIconTextGap(),
               label.getDisplayedMnemonicIndex());

        return size;
    }

    
{@inheritDoc}

/**
     * {@inheritDoc}
     */
    @Override
    public void propertyChange(PropertyChangeEvent e) {
        super.propertyChange(e);
        if (SynthLookAndFeel.shouldUpdateStyle(e)) {
            updateStyle((JLabel)e.getSource());
        }
    }
}