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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package sun.awt.X11;

import java.awt.*;
import java.awt.event.*;
import java.awt.peer.*;
import java.lang.reflect.*;
import sun.awt.AWTAccessor;

class XScrollPanePeer extends XComponentPeer implements ScrollPanePeer, XScrollbarClient {

    public final static int     MARGIN = 1;
    public final static int     SCROLLBAR;
    public final static int     SPACE = 2;
    public final static int     SCROLLBAR_INSET = 2;

    public final static int     VERTICAL = 1 << 0;
    public final static int     HORIZONTAL = 1 << 1;

    static {
        SCROLLBAR = XToolkit.getUIDefaults().getInt("ScrollBar.defaultWidth");
    }

    XVerticalScrollbar       vsb;
    XHorizontalScrollbar     hsb;
    XWindow                  clip;

    int                         active=VERTICAL;
    int                         hsbSpace;
    int                         vsbSpace;

    static class XScrollPaneContentWindow extends XWindow {
        XScrollPaneContentWindow(ScrollPane target, long parentWindow) {
            super(target, parentWindow);
        }
        public String getWMName() {
            return "ScrollPane content";
        }
    }

    XScrollPanePeer(ScrollPane target) {
        super(target);

        // Create the clip window. The field "clip" must be null when
        // we call winCreate, or the parent of clip will be set to itself!
        clip = null;


        XWindow c = new XScrollPaneContentWindow(target,window);
        clip = c;

        vsb = new XVerticalScrollbar(this);

        hsb = new XHorizontalScrollbar(this);

        if (target.getScrollbarDisplayPolicy() == ScrollPane.SCROLLBARS_ALWAYS) {
            vsbSpace = hsbSpace = SCROLLBAR;
        } else {
            vsbSpace = hsbSpace = 0;
        }

        int unitIncrement = 1;
        Adjustable vAdjustable = target.getVAdjustable();
        if (vAdjustable != null){
            unitIncrement = vAdjustable.getUnitIncrement();
        }
        int h = height-hsbSpace;
        vsb.setValues(0, h, 0, h, unitIncrement, Math.max(1, (int)(h * 0.90)));
        vsb.setSize(vsbSpace-SCROLLBAR_INSET, h);

        unitIncrement = 1;
        Adjustable hAdjustable = target.getHAdjustable();
        if (hAdjustable != null){
            unitIncrement = hAdjustable.getUnitIncrement();
        }
        int w = width - vsbSpace;
        hsb.setValues(0, w, 0, w, unitIncrement, Math.max(1, (int)(w * 0.90)));
        hsb.setSize(w, hsbSpace-SCROLLBAR_INSET);

        setViewportSize();
        clip.xSetVisible(true);


    }

    public long getContentWindow()
    {
        return (clip == null) ? window : clip.getWindow();
    }

    public void setBounds(int x, int y, int w, int h, int op) {
        super.setBounds(x, y, w, h, op);

        if (clip == null) return;
        setScrollbarSpace();
        setViewportSize();
        repaint();
    }

    public Insets getInsets() {
        return new Insets(MARGIN, MARGIN, MARGIN+hsbSpace, MARGIN+vsbSpace);
    }

    public int getHScrollbarHeight() {
        return SCROLLBAR;
    }

    public int getVScrollbarWidth() {
        return SCROLLBAR;
    }

    public void childResized(int w, int h) {
        if (setScrollbarSpace()) {
            setViewportSize();
        }
        repaint();
    }

    Dimension getChildSize() {
        ScrollPane sp = (ScrollPane)target;
        if (sp.countComponents() > 0) {
            Component c = sp.getComponent(0);
            return c.size();
        } else {
            return new Dimension(0, 0);
        }
    }

    boolean setScrollbarSpace() {
        ScrollPane sp = (ScrollPane)target;
        boolean changed = false;
        int sbDisplayPolicy = sp.getScrollbarDisplayPolicy();

        if (sbDisplayPolicy == ScrollPane.SCROLLBARS_NEVER) {
            return changed;
        }
        Dimension cSize = getChildSize();

        if (sbDisplayPolicy == ScrollPane.SCROLLBARS_AS_NEEDED) {
            int oldHsbSpace = hsbSpace;
            int oldVsbSpace = vsbSpace;
            hsbSpace = (cSize.width <= (width - 2*MARGIN) ? 0 : SCROLLBAR);
            vsbSpace = (cSize.height <= (height - 2*MARGIN) ? 0 : SCROLLBAR);

            if (hsbSpace == 0 && vsbSpace != 0) {
                hsbSpace = (cSize.width <= (width - SCROLLBAR - 2*MARGIN) ? 0 : SCROLLBAR);
            }
            if (vsbSpace == 0 && hsbSpace != 0) {
                vsbSpace = (cSize.height <= (height - SCROLLBAR - 2*MARGIN) ? 0 : SCROLLBAR);
            }
            if (oldHsbSpace != hsbSpace || oldVsbSpace != vsbSpace) {
                changed = true;
            }
        }
        if (vsbSpace > 0) {
            int vis = height - (2*MARGIN) - hsbSpace;
            int max = Math.max(cSize.height, vis);
            vsb.setValues(vsb.getValue(), vis, 0, max);
            vsb.setBlockIncrement((int)(vsb.getVisibleAmount() * .90));
            vsb.setSize(vsbSpace-SCROLLBAR_INSET, height-hsbSpace);
            // Adjustable vadj = sp.getVAdjustable();
            // vadj.setVisibleAmount(vsb.vis);
            // vadj.setMaximum(vsb.max);
            // vadj.setBlockIncrement(vsb.page);
        }
        if (hsbSpace > 0) {
            int vis = width - (2*MARGIN) - vsbSpace;
            int max = Math.max(cSize.width, vis);
            hsb.setValues(hsb.getValue(), vis, 0, max);
            hsb.setBlockIncrement((int)(hsb.getVisibleAmount() * .90));
            hsb.setSize(width-vsbSpace, hsbSpace-SCROLLBAR_INSET);
            // Adjustable hadj = sp.getHAdjustable();
            // hadj.setVisibleAmount(hsb.vis);
            // hadj.setMaximum(hsb.max);
            // hadj.setBlockIncrement(hsb.page);
        }

        // Check to see if we hid either of the scrollbars but left
        // ourselves scrolled off of the top and/or right of the pane.
        // If we did, we need to scroll to the top and/or right of of
        // the pane to make it visible.
        //
        // Reminder: see if there is a better place to put this code.
        boolean must_scroll = false;

        // Get the point at which the ScrollPane is currently located
        // if number of components > 0
        Point p = new Point(0, 0);

        if (((ScrollPane)target).getComponentCount() > 0){

            p = ((ScrollPane)target).getComponent(0).location();

            if ((vsbSpace == 0) && (p.y < 0)) {
                p.y = 0;
                must_scroll = true;
            }

            if ((hsbSpace == 0) && (p.x < 0)) {
                p.x = 0;
                must_scroll = true;
            }
        }

        if (must_scroll)
            scroll(x, y, VERTICAL | HORIZONTAL);

        return changed;
    }

    void setViewportSize() {
        clip.xSetBounds(MARGIN, MARGIN,
                width - (2*MARGIN)  - vsbSpace,
                height - (2*MARGIN) - hsbSpace);
    }

    public void setUnitIncrement(Adjustable adj, int u) {
        if (adj.getOrientation() == Adjustable.VERTICAL) {
            vsb.setUnitIncrement(u);
        } else {
            // HORIZONTAL
            hsb.setUnitIncrement(u);
        }
    }

    public void setValue(Adjustable adj, int v) {
        if (adj.getOrientation() == Adjustable.VERTICAL) {
            scroll(-1, v, VERTICAL);
        } else {
            // HORIZONTAL
            scroll(v, -1, HORIZONTAL);
        }
    }

    public void setScrollPosition(int x, int y) {
        scroll(x, y, VERTICAL | HORIZONTAL);
    }

    void scroll(int x, int y, int flag) {
        scroll(x, y, flag, AdjustmentEvent.TRACK);
    }

    
Scroll the contents to position x, y
/** * Scroll the contents to position x, y */
void scroll(int x, int y, int flag, int type) { checkSecurity(); ScrollPane sp = (ScrollPane)target; Component c = getScrollChild(); if (c == null) { return; } int sx, sy; Color colors[] = getGUIcolors(); if (sp.getScrollbarDisplayPolicy() == ScrollPane.SCROLLBARS_NEVER) { sx = -x; sy = -y; } else { Point p = c.location(); sx = p.x; sy = p.y; if ((flag & HORIZONTAL) != 0) { hsb.setValue(Math.min(x, hsb.getMaximum()-hsb.getVisibleAmount())); ScrollPaneAdjustable hadj = (ScrollPaneAdjustable)sp.getHAdjustable(); setAdjustableValue(hadj, hsb.getValue(), type); sx = -(hsb.getValue()); Graphics g = getGraphics(); try { paintHorScrollbar(g, colors, true); } finally { g.dispose(); } } if ((flag & VERTICAL) != 0) { vsb.setValue(Math.min(y, vsb.getMaximum() - vsb.getVisibleAmount())); ScrollPaneAdjustable vadj = (ScrollPaneAdjustable)sp.getVAdjustable(); setAdjustableValue(vadj, vsb.getValue(), type); sy = -(vsb.getValue()); Graphics g = getGraphics(); try { paintVerScrollbar(g, colors, true); } finally { g.dispose(); } } } c.move(sx, sy); } void setAdjustableValue(ScrollPaneAdjustable adj, int value, int type) { AWTAccessor.getScrollPaneAdjustableAccessor().setTypedValue(adj, value, type); } public void paint(Graphics g) { paintComponent(g); } void paintScrollBars(Graphics g, Color[] colors) { if (vsbSpace > 0) { paintVerScrollbar(g, colors, true); // paint the whole scrollbar } if (hsbSpace > 0) { paintHorScrollbar(g, colors, true); // paint the whole scrollbar } } void repaintScrollBars() { Graphics g = getGraphics(); Color colors[] = getGUIcolors(); if (g != null) { paintScrollBars(g,colors); } g.dispose(); } public void repaintScrollbarRequest(XScrollbar sb) { Graphics g = getGraphics(); Color colors[] = getGUIcolors(); if (g != null) { if (sb == vsb) { paintVerScrollbar(g,colors,true); } else if (sb == hsb) { paintHorScrollbar(g,colors,true); } } }
Paint the scrollpane.
/** * Paint the scrollpane. */
public void paintComponent(Graphics g) { Color colors[] = getGUIcolors(); g.setColor(colors[BACKGROUND_COLOR]); int h = height - hsbSpace; int w = width - vsbSpace; g.fillRect(0, 0, w, h); // paint rectangular region between scrollbars g.fillRect(w, h, vsbSpace, hsbSpace); if (MARGIN > 0) { draw3DRect(g, colors, 0, 0, w - 1, h - 1, false); } paintScrollBars(g,colors); } public void handleEvent(java.awt.AWTEvent e) { super.handleEvent(e); int id = e.getID(); switch(id) { case PaintEvent.PAINT: case PaintEvent.UPDATE: repaintScrollBars(); break; } }
Paint the horizontal scrollbar to the screen
Params:
  • g – the graphics context to draw into
  • colors – the colors used to draw the scrollbar
  • paintAll – paint the whole scrollbar if true, just the thumb if false
/** * Paint the horizontal scrollbar to the screen * * @param g the graphics context to draw into * @param colors the colors used to draw the scrollbar * @param paintAll paint the whole scrollbar if true, just the thumb if false */
void paintHorScrollbar(Graphics g, Color colors[], boolean paintAll) { if (hsbSpace <= 0) { return; } Graphics ng = g.create(); g.setColor(colors[BACKGROUND_COLOR]); // SCROLLBAR is the height of scrollbar area // but the actual scrollbar is SCROLLBAR-SPACE high; // the rest must be filled with background color int w = width - vsbSpace - (2*MARGIN); g.fillRect(MARGIN, height-SCROLLBAR, w, SPACE); g.fillRect(0, height-SCROLLBAR, MARGIN, SCROLLBAR); g.fillRect(MARGIN + w, height-SCROLLBAR, MARGIN, SCROLLBAR); try { ng.translate(MARGIN, height - (SCROLLBAR - SPACE)); hsb.paint(ng, colors, paintAll); } finally { ng.dispose(); } }
Paint the vertical scrollbar to the screen
Params:
  • g – the graphics context to draw into
  • colors – the colors used to draw the scrollbar
  • paintAll – paint the whole scrollbar if true, just the thumb if false
/** * Paint the vertical scrollbar to the screen * * @param g the graphics context to draw into * @param colors the colors used to draw the scrollbar * @param paintAll paint the whole scrollbar if true, just the thumb if false */
void paintVerScrollbar(Graphics g, Color colors[], boolean paintAll) { if (vsbSpace <= 0) { return; } Graphics ng = g.create(); g.setColor(colors[BACKGROUND_COLOR]); // SCROLLBAR is the width of scrollbar area // but the actual scrollbar is SCROLLBAR-SPACE wide; // the rest must be filled with background color int h = height - hsbSpace - (2*MARGIN); g.fillRect(width-SCROLLBAR, MARGIN, SPACE, h); g.fillRect(width-SCROLLBAR, 0, SCROLLBAR, MARGIN); g.fillRect(width-SCROLLBAR, MARGIN+h, SCROLLBAR, MARGIN); try { ng.translate(width - (SCROLLBAR - SPACE), MARGIN); vsb.paint(ng, colors, paintAll); } finally { ng.dispose(); } }
See Also:
  • MouseEvent.MOUSE_CLICKED MouseEvent.MOUSE_PRESSED MouseEvent.MOUSE_RELEASED MouseEvent.MOUSE_MOVED MouseEvent.MOUSE_ENTERED MouseEvent.MOUSE_EXITED MouseEvent.MOUSE_DRAGGED
/** * * @see java.awt.event.MouseEvent * MouseEvent.MOUSE_CLICKED * MouseEvent.MOUSE_PRESSED * MouseEvent.MOUSE_RELEASED * MouseEvent.MOUSE_MOVED * MouseEvent.MOUSE_ENTERED * MouseEvent.MOUSE_EXITED * MouseEvent.MOUSE_DRAGGED */
public void handleJavaMouseEvent( MouseEvent mouseEvent ) { super.handleJavaMouseEvent(mouseEvent); int modifiers = mouseEvent.getModifiers(); int id = mouseEvent.getID(); int x = mouseEvent.getX(); int y = mouseEvent.getY(); // super.handleMouseEvent(mouseEvent); if ((modifiers & InputEvent.BUTTON1_MASK) == 0) { return; } switch (id) { case MouseEvent.MOUSE_PRESSED: if (inVerticalScrollbar(x,y )) { active = VERTICAL; int h = height - hsbSpace - (2*MARGIN); vsb.handleMouseEvent(id,modifiers,x - (width - SCROLLBAR + SPACE),y-MARGIN); } else if (inHorizontalScrollbar(x, y) ) { active = HORIZONTAL; int w = width - 2*MARGIN - vsbSpace; hsb.handleMouseEvent(id,modifiers,x-MARGIN,y-(height - SCROLLBAR + SPACE)); } break; // On mouse up, pass the event through to the scrollbar to stop // scrolling. The x & y passed do not matter. case MouseEvent.MOUSE_RELEASED: // winReleaseCursorFocus(); if (active == VERTICAL) { vsb.handleMouseEvent(id,modifiers,x,y); } else if (active == HORIZONTAL) { hsb.handleMouseEvent(id,modifiers,x,y); } break; case MouseEvent.MOUSE_DRAGGED: if ((active == VERTICAL)) { int h = height - 2*MARGIN - hsbSpace; vsb.handleMouseEvent(id,modifiers,x-(width - SCROLLBAR + SPACE),y-MARGIN); } else if ((active == HORIZONTAL)) { int w = width - 2*MARGIN - vsbSpace; hsb.handleMouseEvent(id,modifiers,x-MARGIN,y-(height - SCROLLBAR + SPACE)); } break; } }
return value from the scrollbar
/** * return value from the scrollbar */
public void notifyValue(XScrollbar obj, int type, int v, boolean isAdjusting) { if (obj == vsb) { scroll(-1, v, VERTICAL, type); } else if ((XHorizontalScrollbar)obj == hsb) { scroll(v, -1, HORIZONTAL, type); } }
return true if the x and y position is in the verticalscrollbar
/** * return true if the x and y position is in the verticalscrollbar */
boolean inVerticalScrollbar(int x, int y) { if (vsbSpace <= 0) { return false; } int h = height - MARGIN - hsbSpace; return (x >= width - (SCROLLBAR - SPACE)) && (x < width) && (y >= MARGIN) && (y < h); }
return true if the x and y position is in the horizontal scrollbar
/** * return true if the x and y position is in the horizontal scrollbar */
boolean inHorizontalScrollbar(int x, int y) { if (hsbSpace <= 0) { return false; } int w = width - MARGIN - vsbSpace; return (x >= MARGIN) && (x < w) && (y >= height - (SCROLLBAR - SPACE)) && (y < height); } private Component getScrollChild() { ScrollPane sp = (ScrollPane)target; Component child = null; try { child = sp.getComponent(0); } catch (ArrayIndexOutOfBoundsException e) { // do nothing. in this case we return null } return child; } int vval; int hval; int vmax; int hmax; /* * Print the native component by rendering the Motif look ourselves. * ToDo(aim): needs to query native motif for more accurate size and * color information. */ public void print(Graphics g) { ScrollPane sp = (ScrollPane)target; Dimension d = sp.size(); Color bg = sp.getBackground(); Color fg = sp.getForeground(); Point p = sp.getScrollPosition(); Component c = getScrollChild(); Dimension cd; if (c != null) { cd = c.size(); } else { cd = new Dimension(0, 0); } int sbDisplay = sp.getScrollbarDisplayPolicy(); int vvis, hvis, vmin, hmin, vmax, hmax, vval, hval; switch (sbDisplay) { case ScrollPane.SCROLLBARS_NEVER: hsbSpace = vsbSpace = 0; break; case ScrollPane.SCROLLBARS_ALWAYS: hsbSpace = vsbSpace = SCROLLBAR; break; case ScrollPane.SCROLLBARS_AS_NEEDED: hsbSpace = (cd.width <= (d.width - 2*MARGIN)? 0 : SCROLLBAR); vsbSpace = (cd.height <= (d.height - 2*MARGIN)? 0 : SCROLLBAR); if (hsbSpace == 0 && vsbSpace != 0) { hsbSpace = (cd.width <= (d.width - SCROLLBAR - 2*MARGIN)? 0 : SCROLLBAR); } if (vsbSpace == 0 && hsbSpace != 0) { vsbSpace = (cd.height <= (d.height - SCROLLBAR - 2*MARGIN)? 0 : SCROLLBAR); } } vvis = hvis = vmin = hmin = vmax = hmax = vval = hval = 0; if (vsbSpace > 0) { vmin = 0; vvis = d.height - (2*MARGIN) - hsbSpace; vmax = Math.max(cd.height - vvis, 0); vval = p.y; } if (hsbSpace > 0) { hmin = 0; hvis = d.width - (2*MARGIN) - vsbSpace; hmax = Math.max(cd.width - hvis, 0); hval = p.x; } // need to be careful to add the margins back in here because // we're drawing the margin border, after all! int w = d.width - vsbSpace; int h = d.height - hsbSpace; g.setColor(bg); g.fillRect(0, 0, d.width, d.height); if (hsbSpace > 0) { int sbw = d.width - vsbSpace; g.fillRect(1, d.height - SCROLLBAR - 3, sbw - 1, SCROLLBAR - 3); Graphics ng = g.create(); try { ng.translate(0, d.height - (SCROLLBAR - 2)); drawScrollbar(ng, bg, SCROLLBAR - 2, sbw, hmin, hmax, hval, hvis, true); } finally { ng.dispose(); } } if (vsbSpace > 0) { int sbh = d.height - hsbSpace; g.fillRect(d.width - SCROLLBAR - 3, 1, SCROLLBAR - 3, sbh - 1); Graphics ng = g.create(); try { ng.translate(d.width - (SCROLLBAR - 2), 0); drawScrollbar(ng, bg, SCROLLBAR - 2, sbh, vmin, vmax, vval, vvis, false); } finally { ng.dispose(); } } draw3DRect(g, bg, 0, 0, w - 1, h - 1, false); target.print(g); sp.printComponents(g); } }