imageitem.java

用于移动设备上的java虚拟机源代码

        if (numCommands >= 1) {
            if (this.appearanceMode == Item.BUTTON) {
                return img.getHeight() + getLabelHeight(w) +
                       (BUTTON_BORDER + BUTTON_PAD) * 2;
            } else if (this.appearanceMode == Item.HYPERLINK) {
                return img.getHeight() + getLabelHeight(w) +
                       (HYPERLINK_IMG.getHeight() + HYPERLINK_PAD) * 2;
            }
        }

        return img.getHeight() + getLabelHeight(w);
    }

    /**
     * Paint this ImageItem
     *
     * @param g the Graphics context to paint to
     * @param width the width of this ImageItem
     * @param height the height of this ImageItem
     */
    void callPaint(Graphics g, int width, int height) {

        int labelHeight = super.paintLabel(g, width);

        if (img == null) {
            return;
        }

        int x = 0;
        int y = labelHeight;
        int l = getLayout() & ImageItem.LAYOUT_CENTER;

        if (l == ImageItem.LAYOUT_CENTER) {
            x = width / 2;
            if ((numCommands >= 1) &&
               (this.appearanceMode == Item.BUTTON)) {
                x += BUTTON_BORDER + BUTTON_PAD;
                y += BUTTON_BORDER + BUTTON_PAD;
            } else if ((numCommands >= 1) &&
                (this.appearanceMode == Item.HYPERLINK)) {
                x += VERTICAL_HYPERLINK_IMG.getWidth() + HYPERLINK_PAD;
                y += HYPERLINK_IMG.getHeight() + HYPERLINK_PAD;
            }

            g.drawImage(img, x, y,
                        Graphics.TOP | Graphics.HCENTER);

        } else if (l == ImageItem.LAYOUT_RIGHT) {
            x = width;
            if ((numCommands >= 1) &&
               (this.appearanceMode == Item.BUTTON)) {
                x -= (BUTTON_BORDER + BUTTON_PAD);
                y += BUTTON_BORDER + BUTTON_PAD;
            } else if ((numCommands >= 1) &&
                (this.appearanceMode == Item.HYPERLINK)) {
                x -= VERTICAL_HYPERLINK_IMG.getWidth() + HYPERLINK_PAD;
                y += HYPERLINK_IMG.getHeight() + HYPERLINK_PAD;
            }

            g.drawImage(img, x, y,
                        Graphics.TOP | Graphics.RIGHT);

        } else {
            // use x = 0;
            if ((numCommands >= 1) &&
               (this.appearanceMode == Item.BUTTON)) {
                x += BUTTON_BORDER + BUTTON_PAD;
                y += BUTTON_BORDER + BUTTON_PAD;
            } else if ((numCommands >= 1) &&
                (this.appearanceMode == Item.HYPERLINK)) {
                x += VERTICAL_HYPERLINK_IMG.getWidth() + HYPERLINK_PAD;
                y += HYPERLINK_IMG.getHeight() + HYPERLINK_PAD;
            }

            g.drawImage(img, x, y,
                        Graphics.TOP | Graphics.LEFT);
        }

        // draw the button border or hyperlink image

        if ((numCommands >= 1) &&
            (this.appearanceMode == Item.BUTTON)) {
            int w = img.getWidth();
            int h = img.getHeight();
            // y = labelHeight + vertPad/2;
            y = labelHeight;

            if (l == ImageItem.LAYOUT_CENTER) {
                x = (width / 2) - (w / 2);
            } else if (l == ImageItem.LAYOUT_RIGHT) {
                x = width - w - 2 * (BUTTON_BORDER + BUTTON_PAD);
            } else {
                x = 0;
            }

            w += 2 * (BUTTON_BORDER + BUTTON_PAD);
            h += 2 * (BUTTON_BORDER + BUTTON_PAD);
            drawButtonBorder(g, x, y, w, h, hasFocus);

        } else if ((numCommands >= 1) &&
            (this.appearanceMode == Item.HYPERLINK)) {
            // NOTE: We test to see if the width of the Image
            // in the ImageItem is
            // wider than the width of the hyperlink image,
            // if so, we re-draw
            // the image offset to the right as many times as necessary
            // to fill the width of the Image in the ImageItem.

            int imageItemWidth = img.getWidth();
            int imageItemHeight = img.getHeight();
            y = labelHeight;

            if (l == ImageItem.LAYOUT_CENTER) {
                drawTop_BottomBorder(g,
                    width / 2 - imageItemWidth / 2
                    - HYPERLINK_PAD - VERTICAL_HYPERLINK_IMG.getWidth(),
                    width / 2 + imageItemWidth / 2 + 2 * HYPERLINK_PAD,
                    y, y + HYPERLINK_IMG.getHeight()
                    + imageItemHeight + 2 * HYPERLINK_PAD);
                drawLeft_RightBorder(g, y,
                    y + imageItemHeight + (2 * HYPERLINK_PAD),
                    width / 2 - imageItemWidth / 2
                    - VERTICAL_HYPERLINK_IMG.getHeight(),
                    width / 2 + imageItemWidth / 2 + 2 * HYPERLINK_PAD);
            } else if (l == ImageItem.LAYOUT_RIGHT) {
                drawTop_BottomBorder(g,
                    width - imageItemWidth
                    - 2 * HYPERLINK_PAD - VERTICAL_HYPERLINK_IMG.getWidth(),
                    width - VERTICAL_HYPERLINK_IMG.getWidth(),
                    y, y + HYPERLINK_IMG.getHeight()
                    + imageItemHeight + 2 * HYPERLINK_PAD);
                drawLeft_RightBorder(g, y,
                    y + imageItemHeight + 2 * HYPERLINK_PAD,
                    width - imageItemWidth
                    - HYPERLINK_PAD - VERTICAL_HYPERLINK_IMG.getHeight(),
                    width - VERTICAL_HYPERLINK_IMG.getWidth());
            } else {
                drawTop_BottomBorder(g, 0,
                    imageItemWidth + 2 * HYPERLINK_PAD,
                    y, y + HYPERLINK_IMG.getHeight()
                    + imageItemHeight + 2 * HYPERLINK_PAD);
                drawLeft_RightBorder(g, y,
                    y + imageItemHeight + 2 * HYPERLINK_PAD,
                    0,  HYPERLINK_IMG.getHeight()
                    + imageItemWidth + 2 * HYPERLINK_PAD);
            }
        }// end if HYPERLINK
    }

    /**
     * Called by the system to signal a key press
     *
     * @param keyCode the key code of the key that has been pressed
     * @see #getInteractionModes
     */
    void callKeyPressed(int keyCode) {
        if (keyCode != Display.KEYCODE_SELECT) {
            return;
        }

        if (getCommandCount() == 0 || commandListener == null) {
            return;
        }

        ItemCommandListener cl = null;
        Command defaultCmd = null;

        synchronized (Display.LCDUILock) {
            cl = commandListener;
            defaultCmd = defaultCommand;
        } // synchronized


        // SYNC NOTE: The call to the listener must occur outside
        // of the lock
        if (cl != null) {
            try {
                // SYNC NOTE: We lock on calloutLock around any calls
                // into application code
                synchronized (Display.calloutLock) {
                    if (defaultCmd != null) {
                        cl.commandAction(defaultCmd, this);
                    } else {
                        // REMINDER : Needs HI decision
                        // either call the first command
                        // from  the command list or
                        // invoke the menu
                    }
                }
            } catch (Throwable thr) {
                Display.handleThrowable(thr);
            }
        }
    }

    /**
     *  Adds a context sensitive Command to the image item.
     * @param cmd the command to be removed
     */

    void addCommandImpl(Command cmd) {
        synchronized (Display.LCDUILock) {
            super.addCommandImpl(cmd);

            if ((numCommands >= 1) && (appearanceMode == Item.PLAIN)) {
                // restore the value of the original appearanceMode
                // if it is a button
                // otherwise simple change the appearanceMode
                // to a hyperlink
                this.appearanceMode =
                    originalAppearanceMode == Item.BUTTON ?
                    Item.BUTTON : Item.HYPERLINK;

                invalidate();
            }
        } // synchronized
    }

    /**
     *  Removes the context sensitive command from item.
     * @param cmd the command to be removed
     */
    void removeCommandImpl(Command cmd) {
        synchronized (Display.LCDUILock) {
            super.removeCommandImpl(cmd);

            if ((numCommands < 1) && (appearanceMode != Item.PLAIN)) {
                // store value of the original appearanceMode
                originalAppearanceMode = this.appearanceMode;
                // change the appearanceMode to plain
                this.appearanceMode = Item.PLAIN;

                // size or appearance changed
                invalidate();
            } 
        } // synchronized
    }

    /**
     * Determine if Form should not traverse to this ImageItem
     *
     * @return true if Form should not traverse to this ImageItem
     */
    boolean shouldSkipTraverse() {
        if ((label == null || label.length() == 0) && (img == null)) {
            return true;
        }

        return false;
    }

    // private

    /**
     * Set the Image for this ImageItem
     *
     * @param img The image to use for this ImageItem
     */
    private void setImageImpl(Image img) {
        if (img != null && img.isMutable()) {
            this.mutImg = img;
            this.img = Image.createImage(img); // use immutable copy of img
        } else { 
            this.mutImg = null;
            this.img = img;
        }
    }

    /**
     * Set the alternate text for this ImageItem
     *
     * @param text The alternate text for this ImageItem
     */
    private void setAltTextImpl(String text) {
        this.altText = text;
    }

    /**
     * Draw Top and Bottom Border for showing Hyperlink ImageItem
     *
     * @param g The Graphics context to paint to
     * @param start start x co-ordinate of ImageItem
     * @param end end x co-ordinate of ImageItem
     * @param y1  y co-ordinate of Top ImageItem
     * @param y2  y co-ordinate of Bottom ImageItem
     */
    private void drawTop_BottomBorder(Graphics g, int start, int end,
                                      int y1, int y2) {

        for (int x = start; x < end; x += HYPERLINK_IMG.getWidth()) {
            // draw the top  border
            g.drawImage(HYPERLINK_IMG, x, y1,
                        Graphics.TOP | Graphics.LEFT);
            // draw the bottom border
            g.drawImage(HYPERLINK_IMG, x, y2,
                        Graphics.TOP | Graphics.LEFT);
        }
    }

    /**
     * Draw Left and Right Border for showing Hyperlink ImageItem
     *
     * @param g The Graphics context to paint to
     * @param start start y co-ordinate of ImageItem
     * @param end end y co-ordinate of ImageItem
     * @param x1  x co-ordinate of Left ImageItem
     * @param x2  x co-ordinate of Right ImageItem
     */
    private void drawLeft_RightBorder(Graphics g, int start, int end, 
                                      int x1, int x2) {

        for (int y = start; y < end; y += VERTICAL_HYPERLINK_IMG.getHeight()) {
            // draw the left border
            g.drawImage(VERTICAL_HYPERLINK_IMG, x1,        y,
                        Graphics.TOP | Graphics.LEFT);
            // draw the right border
            g.drawImage(VERTICAL_HYPERLINK_IMG, x2, y,
                        Graphics.TOP | Graphics.LEFT);
        }
    }

    /**
     * The snapshot of the Image of this ImageItem;
     * If the Image of this ImageItem was set to a mutable Image
     * this variable is updated with a new snapshot each time setImage() is
     * called. 
     */
    private Image img;

    /**
     * If the ImageItem was created with a mutable image or its Image
     * was set to a mutable image, that mutable image is stored in 
     * the mutImg variable so that ImageItem.getImage() could return it.
     */
    private Image mutImg;

    /**
     * The alternate text of this ImageItem
     */
    private String altText;

    /**
     * Vertical padding used for this ImageItem so that it is padded to 
     * occupy whole number of lines.
     */
    private int vertPad;

    /**
     * The appearance hint
     */
    private int appearanceMode;

    /** The original appearance hint before switching */
    private int originalAppearanceMode;

    /** The hyperlink pad used between Hyperlink Border and ImageItem */
    private final static int       HYPERLINK_PAD = 3;

    /** The hyperlink Image to display with the Hyperlink */
    private final static Image     HYPERLINK_IMG;

    /** The Vertical hyperlink Image to display with the Hyperlink */
    private final static Image     VERTICAL_HYPERLINK_IMG;

    static {
        /*
         * Initialize the icons necessary for hyper links.
         */
        VERTICAL_HYPERLINK_IMG = ImmutableImage.createIcon("link_vertical.png");
        HYPERLINK_IMG = ImmutableImage.createIcon("link_horizontal.png");
        com.sun.midp.lcdui.Text.HYPERLINK_IMG = HYPERLINK_IMG;
    }
}