core/org.argeo.suite.ui/src/org/argeo/suite/ui/widgets/ConnectAbstractDropDown.java

   1 package org.argeo.suite.ui.widgets;
   2
   3 import java.util.Arrays;
   4 import java.util.List;
   5
   6 import org.argeo.cms.ui.util.CmsUiUtils;
   7 import org.argeo.eclipse.ui.EclipseUiUtils;
   8 import org.eclipse.rap.rwt.widgets.DropDown;
   9 import org.eclipse.swt.SWT;
  10 import org.eclipse.swt.events.FocusEvent;
  11 import org.eclipse.swt.events.FocusListener;
  12 import org.eclipse.swt.widgets.Event;
  13 import org.eclipse.swt.widgets.Listener;
  14 import org.eclipse.swt.widgets.Text;
  15 import org.eclipse.swt.widgets.Widget;
  16
  17 /**
  18  * Enable easy addition of a {@code DropDown} widget to a text with listeners
  19  * configured
  20  */
  21 public abstract class ConnectAbstractDropDown {
  22
  23         private final Text text;
  24         private final DropDown dropDown;
  25         private boolean modifyFromList = false;
  26
  27         // Current displayed text
  28         private String userText = "";
  29         // Current displayed list items
  30         private String[] values;
  31
  32         // Fine tuning
  33         boolean readOnly;
  34         boolean refreshOnFocus;
  35
  36         /** Implementing classes should call refreshValues() after initialisation */
  37         public ConnectAbstractDropDown(Text text) {
  38                 this(text, SWT.NONE, false);
  39         }
  40
  41         /**
  42          * Implementing classes should call refreshValues() after initialisation
  43          *
  44          * @param text
  45          * @param style
  46          *            only SWT.READ_ONLY is understood, check if the entered text is
  47          *            part of the legal choices.
  48          */
  49         public ConnectAbstractDropDown(Text text, int style) {
  50                 this(text, style, false);
  51         }
  52
  53         /**
  54          * Implementers should call refreshValues() once init has been done.
  55          *
  56          * @param text
  57          * @param style
  58          *            only SWT.READ_ONLY is understood, check if the entered text is
  59          *            part of the legal choices.
  60          * @param refreshOnFocus
  61          *            if true, the possible values are computed each time the focus is
  62          *            gained. It enables, among other to fine tune the getFilteredValues
  63          *            method depending on the current context
  64          */
  65         public ConnectAbstractDropDown(Text text, int style, boolean refreshOnFocus) {
  66                 this.text = text;
  67                 dropDown = new DropDown(text);
  68                 Object obj = dropDown;
  69                 if (obj instanceof Widget)
  70                         CmsUiUtils.markup((Widget) obj);
  71                 readOnly = (style & SWT.READ_ONLY) != 0;
  72                 this.refreshOnFocus = refreshOnFocus;
  73                 addListeners();
  74         }
  75
  76         /**
  77          * Overwrite to force the refresh of the possible values on focus gained event
  78          */
  79         protected boolean refreshOnFocus() {
  80                 return refreshOnFocus;
  81         }
  82
  83         public String getText() {
  84                 return text.getText();
  85         }
  86
  87         public void init() {
  88                 refreshValues();
  89         }
  90
  91         public void reset(String value) {
  92                 modifyFromList = true;
  93                 if (EclipseUiUtils.notEmpty(value))
  94                         text.setText(value);
  95                 else
  96                         text.setText("");
  97                 refreshValues();
  98                 modifyFromList = false;
  99         }
 100
 101         /** Overwrite to provide specific filtering */
 102         protected abstract List<String> getFilteredValues(String filter);
 103
 104         protected void refreshValues() {
 105                 List<String> filteredValues = getFilteredValues(text.getText());
 106                 values = filteredValues.toArray(new String[filteredValues.size()]);
 107                 dropDown.setItems(values);
 108         }
 109
 110         protected void addListeners() {
 111                 addModifyListener();
 112                 addSelectionListener();
 113                 addDefaultSelectionListener();
 114                 addFocusListener();
 115         }
 116
 117         protected void addFocusListener() {
 118                 text.addFocusListener(new FocusListener() {
 119                         private static final long serialVersionUID = -7179112097626535946L;
 120
 121                         public void focusGained(FocusEvent event) {
 122                                 if (refreshOnFocus) {
 123                                         modifyFromList = true;
 124                                         refreshValues();
 125                                         modifyFromList = false;
 126                                 }
 127                                 dropDown.setVisible(true);
 128                         }
 129
 130                         public void focusLost(FocusEvent event) {
 131                                 dropDown.setVisible(false);
 132                                 if (readOnly && values != null && !Arrays.asList(values).contains(userText)) {
 133                                         modifyFromList = true;
 134                                         text.setText("");
 135                                         refreshValues();
 136                                         modifyFromList = false;
 137                                 }
 138                         }
 139                 });
 140         }
 141
 142         private void addSelectionListener() {
 143                 Object obj = dropDown;
 144                 if (obj instanceof Widget)
 145                         ((Widget) obj).addListener(SWT.Selection, new Listener() {
 146                                 private static final long serialVersionUID = -2357157809365135142L;
 147
 148                                 public void handleEvent(Event event) {
 149                                         if (event.index != -1) {
 150                                                 modifyFromList = true;
 151                                                 text.setText(values[event.index]);
 152                                                 modifyFromList = false;
 153                                                 text.selectAll();
 154                                         } else {
 155                                                 text.setText(userText);
 156                                                 text.setSelection(userText.length(), userText.length());
 157                                                 text.setFocus();
 158                                         }
 159                                 }
 160                         });
 161         }
 162
 163         private void addDefaultSelectionListener() {
 164                 Object obj = dropDown;
 165                 if (obj instanceof Widget)
 166                         ((Widget) obj).addListener(SWT.DefaultSelection, new Listener() {
 167                                 private static final long serialVersionUID = -5958008322630466068L;
 168
 169                                 public void handleEvent(Event event) {
 170                                         if (event.index != -1) {
 171                                                 text.setText(values[event.index]);
 172                                                 text.setSelection(event.text.length());
 173                                                 dropDown.setVisible(false);
 174                                         }
 175                                 }
 176                         });
 177         }
 178
 179         private void addModifyListener() {
 180                 text.addListener(SWT.Modify, new Listener() {
 181                         private static final long serialVersionUID = -4373972835244263346L;
 182
 183                         public void handleEvent(Event event) {
 184                                 if (!modifyFromList) {
 185                                         userText = text.getText();
 186                                         refreshValues();
 187                                         if (values.length == 1)
 188                                                 dropDown.setSelectionIndex(0);
 189                                         dropDown.setVisible(true);
 190                                 }
 191                         }
 192                 });
 193         }
 194 }