swt/org.argeo.cms.swt/src/org/argeo/cms/swt/widgets/ContextOverlay.java

   1 package org.argeo.cms.swt.widgets;
   2
   3 import org.argeo.cms.swt.CmsSwtUtils;
   4 import org.eclipse.swt.SWT;
   5 import org.eclipse.swt.events.ShellAdapter;
   6 import org.eclipse.swt.events.ShellEvent;
   7 import org.eclipse.swt.graphics.Point;
   8 import org.eclipse.swt.widgets.Composite;
   9 import org.eclipse.swt.widgets.Control;
  10 import org.eclipse.swt.widgets.Shell;
  11
  12 /**
  13  * Manages a lightweight shell which is related to a {@link Control}, typically
  14  * in order to reproduce a dropdown semantic, but with more flexibility.
  15  */
  16 public class ContextOverlay extends ScrolledPage {
  17         private static final long serialVersionUID = 6702077429573324009L;
  18
  19 //      private Shell shell;
  20         private Control control;
  21
  22         private int maxHeight = 400;
  23
  24         public ContextOverlay(Control control, int style) {
  25                 super(createShell(control, style), SWT.NONE);
  26                 Shell shell = getShell();
  27                 setLayoutData(CmsSwtUtils.fillAll());
  28                 // TODO make autohide configurable?
  29                 //shell.addShellListener(new AutoHideShellListener());
  30                 this.control = control;
  31                 control.addDisposeListener((e) -> {
  32                         dispose();
  33                         shell.dispose();
  34                 });
  35         }
  36
  37         private static Composite createShell(Control control, int style) {
  38                 if (control == null)
  39                         throw new IllegalArgumentException("Control cannot be null");
  40                 if (control.isDisposed())
  41                         throw new IllegalArgumentException("Control is disposed");
  42                 Shell shell = new Shell(control.getShell(), SWT.NO_TRIM);
  43                 shell.setLayout(CmsSwtUtils.noSpaceGridLayout());
  44                 Composite placeholder = new Composite(shell, SWT.BORDER);
  45                 placeholder.setLayoutData(CmsSwtUtils.fillAll());
  46                 placeholder.setLayout(CmsSwtUtils.noSpaceGridLayout());
  47                 return placeholder;
  48         }
  49
  50         public void show() {
  51                 Point relativeControlLocation = control.getLocation();
  52                 Point controlLocation = control.toDisplay(relativeControlLocation.x, relativeControlLocation.y);
  53
  54                 int controlWidth = control.getBounds().width;
  55
  56                 Shell shell = getShell();
  57
  58                 layout(true, true);
  59                 shell.pack();
  60                 shell.layout(true, true);
  61                 int targetShellWidth = shell.getSize().x < controlWidth ? controlWidth : shell.getSize().x;
  62                 if (shell.getSize().y > maxHeight) {
  63                         shell.setSize(targetShellWidth, maxHeight);
  64                 } else {
  65                         shell.setSize(targetShellWidth, shell.getSize().y);
  66                 }
  67
  68                 int shellHeight = shell.getSize().y;
  69                 int controlHeight = control.getBounds().height;
  70                 Point shellLocation = new Point(controlLocation.x, controlLocation.y + controlHeight);
  71                 int displayHeight = shell.getDisplay().getBounds().height;
  72                 if (shellLocation.y + shellHeight > displayHeight) {// bottom of page
  73                         shellLocation = new Point(controlLocation.x, controlLocation.y - shellHeight);
  74                 }
  75                 shell.setLocation(shellLocation);
  76
  77                 if (getChildren().length != 0)
  78                         shell.open();
  79                 if (!control.isDisposed())
  80                         control.setFocus();
  81         }
  82
  83         public void hide() {
  84                 getShell().setVisible(false);
  85                 onHide();
  86         }
  87
  88         public boolean isShellVisible() {
  89                 if (isDisposed())
  90                         return false;
  91                 return getShell().isVisible();
  92         }
  93
  94         /** to be overridden */
  95         protected void onHide() {
  96                 // does nothing by default.
  97         }
  98
  99         private class AutoHideShellListener extends ShellAdapter {
 100                 private static final long serialVersionUID = 7743287433907938099L;
 101
 102                 @Override
 103                 public void shellDeactivated(ShellEvent e) {
 104                         try {
 105                                 Thread.sleep(1000);
 106                         } catch (InterruptedException e1) {
 107                                 // silent
 108                         }
 109                         if (!control.isDisposed() && !control.isFocusControl())
 110                                 hide();
 111                 }
 112         }
 113 }