swt/org.argeo.cms.swt/src/org/argeo/cms/swt/dialogs/LightweightDialog.java

   1 package org.argeo.cms.swt.dialogs;
   2
   3 import org.argeo.api.cms.CmsLog;
   4 import org.argeo.cms.ux.widgets.CmsDialog;
   5 import org.argeo.eclipse.ui.EclipseUiException;
   6 import org.eclipse.swt.SWT;
   7 import org.eclipse.swt.events.FocusEvent;
   8 import org.eclipse.swt.events.FocusListener;
   9 import org.eclipse.swt.events.ShellAdapter;
  10 import org.eclipse.swt.events.ShellEvent;
  11 import org.eclipse.swt.graphics.Point;
  12 import org.eclipse.swt.graphics.Rectangle;
  13 import org.eclipse.swt.layout.GridData;
  14 import org.eclipse.swt.layout.GridLayout;
  15 import org.eclipse.swt.widgets.Composite;
  16 import org.eclipse.swt.widgets.Control;
  17 import org.eclipse.swt.widgets.Display;
  18 import org.eclipse.swt.widgets.Shell;
  19
  20 /** Generic lightweight dialog, not based on JFace. */
  21 public class LightweightDialog {
  22         private final static CmsLog log = CmsLog.getLog(LightweightDialog.class);
  23
  24         private Shell parentShell;
  25         private Shell backgroundShell;
  26         private Shell foregoundShell;
  27
  28         private Display display;
  29
  30         private Integer returnCode = null;
  31         private boolean block = true;
  32
  33         private String title;
  34
  35         /** Tries to find a display */
  36         static Display findDisplay() {
  37                 try {
  38                         Display display = Display.getCurrent();
  39                         if (display != null)
  40                                 return display;
  41                         else
  42                                 return Display.getDefault();
  43                 } catch (Exception e) {
  44                         return Display.getCurrent();
  45                 }
  46         }
  47
  48         public LightweightDialog(Shell parentShell) {
  49                 this.parentShell = parentShell;
  50         }
  51
  52         public int open() {
  53                 display = findDisplay();
  54                 if (foregoundShell != null)
  55                         throw new EclipseUiException("There is already a shell");
  56                 backgroundShell = new Shell(parentShell, SWT.ON_TOP);
  57                 backgroundShell.setFullScreen(true);
  58                 // if (parentShell != null) {
  59                 // backgroundShell.setBounds(parentShell.getBounds());
  60                 // } else
  61                 // backgroundShell.setMaximized(true);
  62                 backgroundShell.setAlpha(128);
  63                 backgroundShell.setBackground(display.getSystemColor(SWT.COLOR_BLACK));
  64                 foregoundShell = new Shell(backgroundShell, SWT.NO_TRIM | SWT.ON_TOP);
  65                 if (title != null)
  66                         setTitle(title);
  67                 foregoundShell.setLayout(new GridLayout());
  68                 foregoundShell.setSize(getInitialSize());
  69                 createDialogArea(foregoundShell);
  70                 // shell.pack();
  71                 // shell.layout();
  72
  73                 Rectangle shellBounds = parentShell != null ? parentShell.getBounds() : display.getBounds();// RAP
  74                 Point dialogSize = foregoundShell.getSize();
  75                 int x = shellBounds.x + (shellBounds.width - dialogSize.x) / 2;
  76                 int y = shellBounds.y + (shellBounds.height - dialogSize.y) / 2;
  77                 foregoundShell.setLocation(x, y);
  78
  79                 foregoundShell.addShellListener(new ShellAdapter() {
  80                         private static final long serialVersionUID = -2701270481953688763L;
  81
  82                         @Override
  83                         public void shellDeactivated(ShellEvent e) {
  84                                 if (hasChildShells())
  85                                         return;
  86                                 if (returnCode == null)// not yet closed
  87                                         closeShell(CmsDialog.CANCEL);
  88                         }
  89
  90                         @Override
  91                         public void shellClosed(ShellEvent e) {
  92                                 notifyClose();
  93                         }
  94
  95                 });
  96
  97                 backgroundShell.open();
  98                 foregoundShell.open();
  99                 // after the foreground shell has been opened
 100                 backgroundShell.addFocusListener(new FocusListener() {
 101                         private static final long serialVersionUID = 3137408447474661070L;
 102
 103                         @Override
 104                         public void focusLost(FocusEvent event) {
 105                         }
 106
 107                         @Override
 108                         public void focusGained(FocusEvent event) {
 109                                 if (hasChildShells())
 110                                         return;
 111                                 if (returnCode == null)// not yet closed
 112                                         closeShell(CmsDialog.CANCEL);
 113                         }
 114                 });
 115                 backgroundShell.addDisposeListener((event) -> onClose());
 116
 117                 if (block) {
 118                         block();
 119                 }
 120                 if (returnCode == null)
 121                         returnCode = CmsDialog.OK;
 122                 return returnCode;
 123         }
 124
 125         public void block() {
 126                 try {
 127                         runEventLoop(foregoundShell);
 128                 } catch (ThreadDeath t) {
 129                         returnCode = CmsDialog.CANCEL;
 130                         if (log.isTraceEnabled())
 131                                 log.error("Thread death, canceling dialog", t);
 132                 } catch (Throwable t) {
 133                         returnCode = CmsDialog.CANCEL;
 134                         log.error("Cannot open blocking lightweight dialog", t);
 135                 }
 136         }
 137
 138         private boolean hasChildShells() {
 139                 if (foregoundShell == null)
 140                         return false;
 141                 return foregoundShell.getShells().length != 0;
 142         }
 143
 144         protected void onClose() {
 145
 146         }
 147
 148         // public synchronized int openAndWait() {
 149         // open();
 150         // while (returnCode == null)
 151         // try {
 152         // wait(100);
 153         // } catch (InterruptedException e) {
 154         // // silent
 155         // }
 156         // return returnCode;
 157         // }
 158
 159         private synchronized void notifyClose() {
 160                 if (returnCode == null)
 161                         returnCode = CmsDialog.CANCEL;
 162                 notifyAll();
 163         }
 164
 165         protected void closeShell(int returnCode) {
 166                 this.returnCode = returnCode;
 167                 if (CmsDialog.CANCEL == returnCode)
 168                         onCancel();
 169                 if (foregoundShell != null && !foregoundShell.isDisposed()) {
 170                         foregoundShell.close();
 171                         foregoundShell.dispose();
 172                         foregoundShell = null;
 173                 }
 174
 175                 if (backgroundShell != null && !backgroundShell.isDisposed()) {
 176                         backgroundShell.close();
 177                         backgroundShell.dispose();
 178                 }
 179         }
 180
 181         protected Point getInitialSize() {
 182                 return new Point(600, 400);
 183         }
 184
 185         protected Control createDialogArea(Composite parent) {
 186                 Composite dialogarea = new Composite(parent, SWT.NONE);
 187                 dialogarea.setLayout(new GridLayout());
 188                 dialogarea.setLayoutData(new GridData(SWT.FILL, SWT.FILL, true, true));
 189                 return dialogarea;
 190         }
 191
 192         protected Shell getBackgroundShell() {
 193                 return backgroundShell;
 194         }
 195
 196         protected Shell getForegoundShell() {
 197                 return foregoundShell;
 198         }
 199
 200         public void setBlockOnOpen(boolean shouldBlock) {
 201                 block = shouldBlock;
 202         }
 203
 204         public void pack() {
 205                 foregoundShell.pack();
 206         }
 207
 208         private void runEventLoop(Shell loopShell) {
 209                 Display display;
 210                 if (foregoundShell == null) {
 211                         display = Display.getCurrent();
 212                 } else {
 213                         display = loopShell.getDisplay();
 214                 }
 215
 216                 while (loopShell != null && !loopShell.isDisposed()) {
 217                         try {
 218                                 if (!display.readAndDispatch()) {
 219                                         display.sleep();
 220                                 }
 221                         } catch (UnsupportedOperationException e) {
 222                                 throw e;
 223                         } catch (Throwable e) {
 224                                 handleException(e);
 225                         }
 226                 }
 227                 if (!display.isDisposed())
 228                         display.update();
 229         }
 230
 231         protected void handleException(Throwable t) {
 232                 if (t instanceof ThreadDeath) {
 233                         // Don't catch ThreadDeath as this is a normal occurrence when
 234                         // the thread dies
 235                         throw (ThreadDeath) t;
 236                 }
 237                 // Try to keep running.
 238                 t.printStackTrace();
 239         }
 240
 241         /** @return false, if the dialog should not be closed. */
 242         protected boolean onCancel() {
 243                 return true;
 244         }
 245
 246         public void setTitle(String title) {
 247                 this.title = title;
 248                 if (title != null && getForegoundShell() != null)
 249                         getForegoundShell().setText(title);
 250         }
 251
 252         public Integer getReturnCode() {
 253                 return returnCode;
 254         }
 255
 256         Display getDisplay() {
 257                 return display;
 258         }
 259
 260 }