自定义SWT控件七之自定义Shell（可伸缩窗口）

7、可伸缩窗口

该自定义窗口可以通过鼠标随意更改窗口大小

package com.hikvision.encapsulate.view.control.shell;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.ShellEvent;
import org.eclipse.swt.events.ShellListener;
import org.eclipse.swt.graphics.Cursor;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Shell;

import com.hikvision.encapsulate.view.swt.SWTResourceManager;

/**
 * <p>自定义shell，该shell仅适用于无标题，即 style == SWT.NO_TRIM使用,提供放大缩小功能</p>
 * @author wangfang5 2018年6月11日 下午2:32:07
 * @version V1.0
 */
public class DefinedShell extends Shell {
    private Point lastPos;
    private boolean drag = false;
    /**
     * <p>锚点对象</p>
     * @author wangfang5 2018年6月11日 下午1:39:43
     * @version V1.0
     */
    private class Anchor {
         /**
         * 锚点的光标对象
         */
        final Cursor cusor;
        /**
         * 锚点位置计算的掩码
         */
        final Rectangle mask;
        Anchor(Cursor cusor, Rectangle mask) {
            this.cusor = cusor;
            this.mask=mask;
        }
    }
    private int anchorIndex;

     // 光标定义
    private final Cursor CURSOR_SIZENESW=new Cursor(Display.getDefault(),SWT.CURSOR_SIZENESW);
    private final Cursor CURSOR_SIZENS=new Cursor(Display.getDefault(),SWT.CURSOR_SIZENS);
    private final Cursor CURSOR_SIZENWSE=new Cursor(Display.getDefault(),SWT.CURSOR_SIZENWSE);
    private final Cursor CURSOR_SIZEWE=new Cursor(Display.getDefault(),SWT.CURSOR_SIZEWE);
    private final Cursor CURSOR_SIZEALL=new Cursor(Display.getDefault(),SWT.CURSOR_SIZEALL);
    //lt+-------+-------+rt
    //  |       t       |
    //  |               |
    //  |       c       |
    //l +       +       +r
    //  |               |
    //  |               |
    //  |       b       |
    //lb+-------+-------+rb
    enum AnchorType{
        LT,T,RT,L,C,R,LB,B,RB
    }

    /**
     * 9个锚点位置({@link Anchor})对象数组(按从左到右从上到下顺序排序)
     */
    private final Anchor[] anchors=new Anchor[]{
            new Anchor(CURSOR_SIZENWSE,new Rectangle(1,1,-1,-1)),
            new Anchor(CURSOR_SIZENS,new Rectangle(0,1,0,-1)),
            new Anchor(CURSOR_SIZENESW,new Rectangle(0,1,1,-1)),
            new Anchor(CURSOR_SIZEWE,new Rectangle(1,0,-1,0)),
            new Anchor(CURSOR_SIZEALL,new Rectangle(1,1,0,0)),
            new Anchor(CURSOR_SIZEWE,new Rectangle(0,0,1,0)),
            new Anchor(CURSOR_SIZENESW,new Rectangle(1,0,-1,1)),
            new Anchor(CURSOR_SIZENS,new Rectangle(0,0,0,1)),
            new Anchor(CURSOR_SIZENWSE,new Rectangle(0,0,1,1))};;  

    public DefinedShell(int style){
        super(style);
        final Cursor defCursor=getCursor();
        this.setBackground(SWTResourceManager.getWhiteColor());
        if((style & SWT.NO_TRIM) != 0){
            getDisplay().addFilter(SWT.MouseDown,event->{
                try{
                    moveAbove(null);
                    Control control = (Control)event.widget;
                    if(control.getData("close") == null){
                        if(event.button == 1 && anchorIndex>=0){
                            drag = true;
                            lastPos = ((Control)(event.widget)).toDisplay(event.x, event.y);
                        }
                    }
                }catch(Throwable e){
                }
            });
            getDisplay().addFilter(SWT.MouseUp, event->{
                drag = false;
            });
            addShellListener(new ShellListener() {

                @Override
                public void shellIconified(ShellEvent e) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void shellDeiconified(ShellEvent e) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void shellDeactivated(ShellEvent e) {
                    drag = false;
                }

                @Override
                public void shellClosed(ShellEvent e) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void shellActivated(ShellEvent e) {
                    // TODO Auto-generated method stub

                }
            });
            getDisplay().addFilter(SWT.MouseMove, event->{
                try{
                    if(drag){ //允许拖拽
                        Point pos=((Control)(event.widget)).toDisplay(event.x, event.y);
                        modify(pos.x-lastPos.x,pos.y-lastPos.y,anchors[anchorIndex].mask);
                        lastPos = pos;
                    }else{
                        //查找相对于shell的坐标
                        Point point = getRelativeShellPoint((Control)event.widget,event.x ,event.y);
                        anchorIndex = getAnchorIndex(point.x ,point.y);
                        if(anchorIndex == -1){  //未选中可以拖拽的边
                            setCursor(defCursor);
                        }else{
                            setCursor(anchors[anchorIndex].cusor);
                        }
                    }
                }catch(Throwable e){
                }
            });
        }
    }

    /**
     * 获取相对于shell的坐标
     * @author wangfang5 2018年6月11日 下午5:14:34
     * @param control
     * @return
     */
    private Point getRelativeShellPoint(Control control,int eventX,int eventY){
        int x = eventX;
        int y = eventY;
        Control now = control;
        while(!(now instanceof Shell)){
            x += now.getBounds().x;
            y += now.getBounds().y;
            now = now.getParent();
        }
        return new Point(x,y);
    }

    @Override
    protected void checkSubclass(){
    }
     /**
     * 改变窗口位置和尺寸
     * @param x x轴移动距离
     * @param y y轴移动距离
     * @param mask 锚点位置计算的掩码
     */
    private void modify(int x,int y,Rectangle mask){
        // 计算出新的窗口位置和尺寸
        Rectangle bound = getBounds();
        bound.x+=x*mask.x;
        bound.y+=y*mask.y;
        bound.width+=x*mask.width;
        bound.height+=y*mask.height;
        // 设置新的窗口位置
        setBounds(bound);
        redraw();
    }

    /**
     * 获取锚点
     * @author wangfang5 2018年6月11日 下午2:00:57
     * @param mousex
     * @param mousey
     * @return
     */
    private int getAnchorIndex(int mousex,int mousey){
        try{
            Rectangle bound = getBounds();
            if(Math.abs(mousex - bound.width) < 10 && mousey < 10){  //右上角、
                 return AnchorType.RT.ordinal();
            }else if(Math.abs(mousey - bound.height) <= 10 && mousex < 10){ //左下角
                return AnchorType.LB.ordinal();
            }if(0 <= mousey && mousey < 10 && 0 <= mousex && mousex < 10){ //左上角
                return AnchorType.LT.ordinal();
            }else if(Math.abs(mousey - bound.height) <= 10 && Math.abs(mousex - bound.width) < 10){ //右下角
                return AnchorType.RB.ordinal();
            }else if (0 <= mousey && mousey < 5) {  //上、
                return AnchorType.T.ordinal();
            } else if(Math.abs(mousey - bound.height) <= 5){ //下
                return AnchorType.B.ordinal();
            }else if (0 <= mousex && mousex< 5) {  //左
                return AnchorType.L.ordinal();
            }else if(Math.abs(mousex - bound.width) <= 5){  //右
                return AnchorType.R.ordinal();
            }else
                return -1;
        }catch(Throwable e){
            return -1;
        }
    }

    @Override
    public void open() {
        // TODO Auto-generated method stub
        super.open();
        drag = false;
    }
}

使用范例：

public MainUI() {
        Display display = Display.getDefault();
        shell = new DefinedShell(SWT.NO_TRIM | SWT.NONE);
        shell.setMinimumSize(shellMinWidth, shellMinHeight);
        shell.setBackground(SWTResourceManager.getColor(51, 51, 51));
        int shellWidth = 1280;
        int shellHeight = 800;
        shell.setMaximized(true);
        shell.setMinimized(true);
        int x = Display.getCurrent().getClientArea().width/2 - shellWidth / 2;
        int y = Display.getCurrent().getClientArea().height / 2 - shellHeight / 2;
        if(x <= 0){
            x =  0;
            shellWidth = Display.getCurrent().getClientArea().width/2;
            if(shellWidth < (shellMinWidth + 100)){
                shellWidth = shellMinWidth + 100;
            }
        }
        if(y<=0){
            y = 0;
            shellHeight = Display.getCurrent().getClientArea().height/2;
            if(shellHeight < (shellMinHeight+100)){
                shellHeight = shellMinHeight+100;
            }
            if((shellHeight + 400)<shellWidth){
                shellWidth = shellHeight + 400;
            }
        }
        shell.setLocation( Display.getCurrent().getClientArea().width/ 2 - shellWidth / 2,
                Display.getCurrent().getClientArea().height / 2 - shellHeight / 2);
        shell.setSize(shellWidth, shellHeight);
}

//若是需要最大化按钮和最小化按钮（自己提供的图标），需要给他们绑上事件，代码如下：
  Label min_label = new Label(tool_bar_composite, SWT.NONE);
  min_label.setBackground(SWTResourceManager.getColor(51, 51, 51));
  min_label.setForeground(SWTResourceManager.getColor(SWT.COLOR_WHITE));
  GridData gd_min_label = new GridData(SWT.RIGHT,SWT.CENTER,true,false,1,1);
  gd_min_label.heightHint = 24;
  gd_min_label.widthHint = 24;
  min_label.setLayoutData(gd_min_label);
  min_label.setImage(ImageUtil.getImage(FileUtil.loadResourceFileAsStream(Constants.MININIZE)));
  min_label.setCursor(SWTResourceManager.getCursor(SWT.CURSOR_HAND));
  min_label.setToolTipText("最小化");
  min_label.addListener(SWT.MouseDown, event ->{
   shell.setMinimized(true);
  });
  
  Label max_label = new Label(tool_bar_composite, SWT.NONE);
  max_label.setBackground(SWTResourceManager.getColor(51, 51, 51));
  max_label.setForeground(SWTResourceManager.getColor(SWT.COLOR_WHITE));
  GridData gd_max_label = new GridData(SWT.RIGHT,SWT.CENTER,true,false,1,1);
  gd_max_label.heightHint = 24;
  gd_max_label.widthHint = 24;
  max_label.setLayoutData(gd_max_label);
  max_label.setImage(ImageUtil.getImage(FileUtil.loadResourceFileAsStream(Constants.MAXIMIZE)));
  max_label.setCursor(SWTResourceManager.getCursor(SWT.CURSOR_HAND));
  max_label.setToolTipText("最大化");
  max_label.addListener(SWT.MouseDown, event ->{
   if(shell.getFullScreen()){
    shell.setFullScreen(false);
    max_label.setImage(ImageUtil.getImage(FileUtil.loadResourceFileAsStream(Constants.MAXIMIZE)));
    max_label.setToolTipText("最大化");
   }else{
    shell.setFullScreen(true);
    max_label.setImage(ImageUtil.getImage(FileUtil.loadResourceFileAsStream(Constants.RESTORE)));
    max_label.setToolTipText("恢复");
   }
  });

以上DefinedShell提供了通过鼠标改变窗口大小功能，范例中提供了放大窗口和缩小窗口功能。