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package sun.awt.im;

import java.awt.AWTEvent;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.InputMethodEvent;
import java.awt.event.InputMethodListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowAdapter;
import java.awt.font.FontRenderContext;
import java.awt.font.TextHitInfo;
import java.awt.font.TextLayout;
import java.awt.geom.Rectangle2D;
import java.awt.im.InputMethodRequests;
import java.text.AttributedCharacterIterator;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.LineBorder;

A composition area is used to display text that's being composed using an input method in its own user interface environment, typically in a root window.
Author:JavaSoft International
/** * A composition area is used to display text that's being composed * using an input method in its own user interface environment, * typically in a root window. * * @author JavaSoft International */
// This class is final due to the 6607310 fix. Refer to the CR for details. public final class CompositionArea extends JPanel implements InputMethodListener { private CompositionAreaHandler handler; private TextLayout composedTextLayout; private TextHitInfo caret = null; private JFrame compositionWindow; private final static int TEXT_ORIGIN_X = 5; private final static int TEXT_ORIGIN_Y = 15; private final static int PASSIVE_WIDTH = 480; private final static int WIDTH_MARGIN=10; private final static int HEIGHT_MARGIN=3; CompositionArea() { // create composition window with localized title String windowTitle = Toolkit.getProperty("AWT.CompositionWindowTitle", "Input Window"); compositionWindow = (JFrame)InputMethodContext.createInputMethodWindow(windowTitle, null, true); setOpaque(true); setBorder(LineBorder.createGrayLineBorder()); setForeground(Color.black); setBackground(Color.white); // if we get the focus, we still want to let the client's // input context handle the event enableInputMethods(true); enableEvents(AWTEvent.KEY_EVENT_MASK); compositionWindow.getContentPane().add(this); compositionWindow.addWindowListener(new FrameWindowAdapter()); addInputMethodListener(this); compositionWindow.enableInputMethods(false); compositionWindow.pack(); Dimension windowSize = compositionWindow.getSize(); Dimension screenSize = (getToolkit()).getScreenSize(); compositionWindow.setLocation(screenSize.width - windowSize.width-20, screenSize.height - windowSize.height-100); compositionWindow.setVisible(false); }
Sets the composition area handler that currently owns this composition area, and its input context.
/** * Sets the composition area handler that currently owns this * composition area, and its input context. */
synchronized void setHandlerInfo(CompositionAreaHandler handler, InputContext inputContext) { this.handler = handler; ((InputMethodWindow) compositionWindow).setInputContext(inputContext); }
See Also:
  • getInputMethodRequests.getInputMethodRequests
/** * @see java.awt.Component#getInputMethodRequests */
public InputMethodRequests getInputMethodRequests() { return handler; } // returns a 0-width rectangle private Rectangle getCaretRectangle(TextHitInfo caret) { int caretLocation = 0; TextLayout layout = composedTextLayout; if (layout != null) { caretLocation = Math.round(layout.getCaretInfo(caret)[0]); } Graphics g = getGraphics(); FontMetrics metrics = null; try { metrics = g.getFontMetrics(); } finally { g.dispose(); } return new Rectangle(TEXT_ORIGIN_X + caretLocation, TEXT_ORIGIN_Y - metrics.getAscent(), 0, metrics.getAscent() + metrics.getDescent()); } public void paint(Graphics g) { super.paint(g); g.setColor(getForeground()); TextLayout layout = composedTextLayout; if (layout != null) { layout.draw((Graphics2D) g, TEXT_ORIGIN_X, TEXT_ORIGIN_Y); } if (caret != null) { Rectangle rectangle = getCaretRectangle(caret); g.setXORMode(getBackground()); g.fillRect(rectangle.x, rectangle.y, 1, rectangle.height); g.setPaintMode(); } } // shows/hides the composition window void setCompositionAreaVisible(boolean visible) { compositionWindow.setVisible(visible); } // returns true if composition area is visible boolean isCompositionAreaVisible() { return compositionWindow.isVisible(); } // workaround for the Solaris focus lost problem class FrameWindowAdapter extends WindowAdapter { public void windowActivated(WindowEvent e) { requestFocus(); } } // InputMethodListener methods - just forward to the current handler public void inputMethodTextChanged(InputMethodEvent event) { handler.inputMethodTextChanged(event); } public void caretPositionChanged(InputMethodEvent event) { handler.caretPositionChanged(event); }
Sets the text and caret to be displayed in this composition area. Shows the window if it contains text, hides it if not.
/** * Sets the text and caret to be displayed in this composition area. * Shows the window if it contains text, hides it if not. */
void setText(AttributedCharacterIterator composedText, TextHitInfo caret) { composedTextLayout = null; if (composedText == null) { // there's no composed text to display, so hide the window compositionWindow.setVisible(false); this.caret = null; } else { /* since we have composed text, make sure the window is shown. This is necessary to get a valid graphics object. See 6181385. */ if (!compositionWindow.isVisible()) { compositionWindow.setVisible(true); } Graphics g = getGraphics(); if (g == null) { return; } try { updateWindowLocation(); FontRenderContext context = ((Graphics2D)g).getFontRenderContext(); composedTextLayout = new TextLayout(composedText, context); Rectangle2D bounds = composedTextLayout.getBounds(); this.caret = caret; // Resize the composition area to just fit the text. FontMetrics metrics = g.getFontMetrics(); Rectangle2D maxCharBoundsRec = metrics.getMaxCharBounds(g); int newHeight = (int)maxCharBoundsRec.getHeight() + HEIGHT_MARGIN; int newFrameHeight = newHeight +compositionWindow.getInsets().top +compositionWindow.getInsets().bottom; // If it's a passive client, set the width always to PASSIVE_WIDTH (480px) InputMethodRequests req = handler.getClientInputMethodRequests(); int newWidth = (req==null) ? PASSIVE_WIDTH : (int)bounds.getWidth() + WIDTH_MARGIN; int newFrameWidth = newWidth + compositionWindow.getInsets().left + compositionWindow.getInsets().right; setPreferredSize(new Dimension(newWidth, newHeight)); compositionWindow.setSize(new Dimension(newFrameWidth, newFrameHeight)); // show the composed text paint(g); } finally { g.dispose(); } } }
Sets the caret to be displayed in this composition area. The text is not changed.
/** * Sets the caret to be displayed in this composition area. * The text is not changed. */
void setCaret(TextHitInfo caret) { this.caret = caret; if (compositionWindow.isVisible()) { Graphics g = getGraphics(); try { paint(g); } finally { g.dispose(); } } }
Positions the composition window near (usually below) the insertion point in the client component if the client component is an active client (below-the-spot input).
/** * Positions the composition window near (usually below) the * insertion point in the client component if the client * component is an active client (below-the-spot input). */
void updateWindowLocation() { InputMethodRequests req = handler.getClientInputMethodRequests(); if (req == null) { // not an active client return; } Point windowLocation = new Point(); Rectangle caretRect = req.getTextLocation(null); Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Dimension windowSize = compositionWindow.getSize(); final int SPACING = 2; if (caretRect.x + windowSize.width > screenSize.width) { windowLocation.x = screenSize.width - windowSize.width; } else { windowLocation.x = caretRect.x; } if (caretRect.y + caretRect.height + SPACING + windowSize.height > screenSize.height) { windowLocation.y = caretRect.y - SPACING - windowSize.height; } else { windowLocation.y = caretRect.y + caretRect.height + SPACING; } compositionWindow.setLocation(windowLocation); } // support for InputMethodRequests methods Rectangle getTextLocation(TextHitInfo offset) { Rectangle rectangle = getCaretRectangle(offset); Point location = getLocationOnScreen(); rectangle.translate(location.x, location.y); return rectangle; } TextHitInfo getLocationOffset(int x, int y) { TextLayout layout = composedTextLayout; if (layout == null) { return null; } else { Point location = getLocationOnScreen(); x -= location.x + TEXT_ORIGIN_X; y -= location.y + TEXT_ORIGIN_Y; if (layout.getBounds().contains(x, y)) { return layout.hitTestChar(x, y); } else { return null; } } } // Disables or enables decorations of the composition window void setCompositionAreaUndecorated(boolean setUndecorated){ if (compositionWindow.isDisplayable()){ compositionWindow.removeNotify(); } compositionWindow.setUndecorated(setUndecorated); compositionWindow.pack(); } // Proclaim serial compatibility with 1.7.0 private static final long serialVersionUID = -1057247068746557444L; }