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

   1 package org.argeo.cms.swt.dialogs;
   2
   3 import org.apache.commons.logging.Log;
   4 import org.apache.commons.logging.LogFactory;
   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 Log log = LogFactory.getLog(LightweightDialog.class);
  23
  24         // must be the same value as org.eclipse.jface.window.Window#OK
  25         public final static int OK = 0;
  26         // must be the same value as org.eclipse.jface.window.Window#CANCEL
  27         public final static int CANCEL = 1;
  28
  29         private Shell parentShell;
  30         private Shell backgroundShell;
  31         private Shell foregoundShell;
  32
  33         private Integer returnCode = null;
  34         private boolean block = true;
  35
  36         private String title;
  37
  38         /** Tries to find a display */
  39         private static Display getDisplay() {
  40                 try {
  41                         Display display = Display.getCurrent();
  42                         if (display != null)
  43                                 return display;
  44                         else
  45                                 return Display.getDefault();
  46                 } catch (Exception e) {
  47                         return Display.getCurrent();
  48                 }
  49         }
  50
  51         public LightweightDialog(Shell parentShell) {
  52                 this.parentShell = parentShell;
  53         }
  54
  55         public int open() {
  56                 if (foregoundShell != null)
  57                         throw new EclipseUiException("There is already a shell");
  58                 backgroundShell = new Shell(parentShell, SWT.ON_TOP);
  59                 backgroundShell.setFullScreen(true);
  60                 // if (parentShell != null) {
  61                 // backgroundShell.setBounds(parentShell.getBounds());
  62                 // } else
  63                 // backgroundShell.setMaximized(true);
  64                 backgroundShell.setAlpha(128);
  65                 backgroundShell.setBackground(getDisplay().getSystemColor(SWT.COLOR_BLACK));
  66                 foregoundShell = new Shell(backgroundShell, SWT.NO_TRIM | SWT.ON_TOP);
  67                 if (title != null)
  68                         setTitle(title);
  69                 foregoundShell.setLayout(new GridLayout());
  70                 foregoundShell.setSize(getInitialSize());
  71                 createDialogArea(foregoundShell);
  72                 // shell.pack();
  73                 // shell.layout();
  74
  75                 Rectangle shellBounds = parentShell != null ? parentShell.getBounds() : Display.getCurrent().getBounds();// RAP
  76                 Point dialogSize = foregoundShell.getSize();
  77                 int x = shellBounds.x + (shellBounds.width - dialogSize.x) / 2;
  78                 int y = shellBounds.y + (shellBounds.height - dialogSize.y) / 2;
  79                 foregoundShell.setLocation(x, y);
  80
  81                 foregoundShell.addShellListener(new ShellAdapter() {
  82                         private static final long serialVersionUID = -2701270481953688763L;
  83
  84                         @Override
  85                         public void shellDeactivated(ShellEvent e) {
  86                                 if (hasChildShells())
  87                                         return;
  88                                 if (returnCode == null)// not yet closed
  89                                         closeShell(CANCEL);
  90                         }
  91
  92                         @Override
  93                         public void shellClosed(ShellEvent e) {
  94                                 notifyClose();
  95                         }
  96
  97                 });
  98
  99                 backgroundShell.open();
 100                 foregoundShell.open();
 101                 // after the foreground shell has been opened
 102                 backgroundShell.addFocusListener(new FocusListener() {
 103                         private static final long serialVersionUID = 3137408447474661070L;
 104
 105                         @Override
 106                         public void focusLost(FocusEvent event) {
 107                         }
 108
 109                         @Override
 110                         public void focusGained(FocusEvent event) {
 111                                 if (hasChildShells())
 112                                         return;
 113                                 if (returnCode == null)// not yet closed
 114                                         closeShell(CANCEL);
 115                         }
 116                 });
 117
 118                 if (block) {
 119                         block();
 120                 }
 121                 if (returnCode == null)
 122                         returnCode = OK;
 123                 return returnCode;
 124         }
 125
 126         public void block() {
 127                 try {
 128                         runEventLoop(foregoundShell);
 129                 } catch (ThreadDeath t) {
 130                         returnCode = CANCEL;
 131                         if (log.isTraceEnabled())
 132                                 log.error("Thread death, canceling dialog", t);
 133                 } catch (Throwable t) {
 134                         returnCode = CANCEL;
 135                         log.error("Cannot open blocking lightweight dialog", t);
 136                 }
 137         }
 138
 139         private boolean hasChildShells() {
 140                 if (foregoundShell == null)
 141                         return false;
 142                 return foregoundShell.getShells().length != 0;
 143         }
 144
 145         // public synchronized int openAndWait() {
 146         // open();
 147         // while (returnCode == null)
 148         // try {
 149         // wait(100);
 150         // } catch (InterruptedException e) {
 151         // // silent
 152         // }
 153         // return returnCode;
 154         // }
 155
 156         private synchronized void notifyClose() {
 157                 if (returnCode == null)
 158                         returnCode = CANCEL;
 159                 notifyAll();
 160         }
 161
 162         protected void closeShell(int returnCode) {
 163                 this.returnCode = returnCode;
 164                 if (CANCEL == returnCode)
 165                         onCancel();
 166                 if (foregoundShell != null && !foregoundShell.isDisposed()) {
 167                         foregoundShell.close();
 168                         foregoundShell.dispose();
 169                         foregoundShell = null;
 170                 }
 171
 172                 if (backgroundShell != null && !backgroundShell.isDisposed()) {
 173                         backgroundShell.close();
 174                         backgroundShell.dispose();
 175                 }
 176         }
 177
 178         protected Point getInitialSize() {
 179                 // if (exception != null)
 180                 // return new Point(800, 600);
 181                 // else
 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 }