case-study/jdt-after/ui/org/eclipse/jdt/internal/ui/text/ChangeHoverInformationControl.java

   1 /*******************************************************************************
   2  * Copyright (c) 2000, 2011 IBM Corporation and others.
   3  * All rights reserved. This program and the accompanying materials
   4  * are made available under the terms of the Eclipse Public License v1.0
   5  * which accompanies this distribution, and is available at
   6  * http://www.eclipse.org/legal/epl-v10.html
   7  *
   8  * Contributors:
   9  *     IBM Corporation - initial API and implementation
  10  *******************************************************************************/
  11 package org.eclipse.jdt.internal.ui.text;
  12
  13 import org.eclipse.swt.custom.StyledText;
  14 import org.eclipse.swt.graphics.Font;
  15 import org.eclipse.swt.graphics.GC;
  16 import org.eclipse.swt.graphics.Point;
  17 import org.eclipse.swt.widgets.Composite;
  18 import org.eclipse.swt.widgets.Control;
  19 import org.eclipse.swt.widgets.Shell;
  20
  21 import org.eclipse.core.runtime.Assert;
  22
  23 import org.eclipse.jface.resource.JFaceResources;
  24
  25 import org.eclipse.jface.text.BadLocationException;
  26 import org.eclipse.jface.text.IDocument;
  27 import org.eclipse.jface.text.IRegion;
  28 import org.eclipse.jface.text.ITextViewerExtension;
  29
  30 import org.eclipse.jdt.ui.text.IJavaPartitions;
  31
  32 import org.eclipse.jdt.internal.ui.text.java.hover.SourceViewerInformationControl;
  33
  34 /**
  35  * Specialized source viewer information control used to display quick diff hovers.
  36  *
  37  * @since 3.0
  38  */
  39 class ChangeHoverInformationControl extends SourceViewerInformationControl {
  40
  41         /** The font name for the viewer font - the same as the java editor's. */
  42         private static final String SYMBOLIC_FONT_NAME= "org.eclipse.jdt.ui.editors.textfont"; //$NON-NLS-1$
  43
  44         /** The maximum width of the control, set in <code>setSizeConstraints(int, int)</code>. */
  45         int fMaxWidth= Integer.MAX_VALUE;
  46         /** The maximum height of the control, set in <code>setSizeConstraints(int, int)</code>. */
  47         int fMaxHeight= Integer.MAX_VALUE;
  48
  49         /** The partition type to be used as the starting partition type by the partition scanner. */
  50         private String fPartition;
  51         /** The horizontal scroll index. */
  52         private int fHorizontalScrollPixel;
  53
  54         /*
  55          * @see org.eclipse.jface.text.IInformationControl#setSizeConstraints(int, int)
  56          */
  57         @Override
  58         public void setSizeConstraints(int maxWidth, int maxHeight) {
  59                 fMaxWidth= maxWidth;
  60                 fMaxHeight= maxHeight;
  61         }
  62
  63         /**
  64          * Creates a new information control.
  65          *
  66          * @param parent the shell that is the parent of this hover / control
  67          * @param isResizable <code>true</code> if resizable
  68          * @param orientation the orientation
  69          * @param partition the initial partition type to be used for the underlying viewer
  70          * @param statusFieldText the text to be used in the optional status field
  71          *                         or <code>null</code> if the status field should be hidden
  72          */
  73         public ChangeHoverInformationControl(Shell parent, boolean isResizable, int orientation, String partition, String statusFieldText) {
  74                 super(parent, isResizable, orientation, statusFieldText);
  75                 setViewerFont();
  76                 setStartingPartitionType(partition);
  77         }
  78
  79         /*
  80          * @see org.eclipse.jface.text.IInformationControl#computeSizeHint()
  81          */
  82         @Override
  83         public Point computeSizeHint() {
  84                 Point size= super.computeSizeHint();
  85                 size.x= Math.min(size.x, fMaxWidth);
  86                 size.y= Math.min(size.y, fMaxHeight);
  87                 return size;
  88         }
  89
  90         /**
  91          * Sets the font for this viewer sustaining selection and scroll position.
  92          */
  93         private void setViewerFont() {
  94                 Font font= JFaceResources.getFont(SYMBOLIC_FONT_NAME);
  95
  96                 if (getViewer().getDocument() != null) {
  97
  98                         Point selection= getViewer().getSelectedRange();
  99                         int topIndex= getViewer().getTopIndex();
 100
 101                         StyledText styledText= getViewer().getTextWidget();
 102                         Control parent= styledText;
 103                         if (getViewer() instanceof ITextViewerExtension) {
 104                                 ITextViewerExtension extension= (ITextViewerExtension) getViewer();
 105                                 parent= extension.getControl();
 106                         }
 107
 108                         parent.setRedraw(false);
 109
 110                         styledText.setFont(font);
 111
 112                         getViewer().setSelectedRange(selection.x , selection.y);
 113                         getViewer().setTopIndex(topIndex);
 114
 115                         if (parent instanceof Composite) {
 116                                 Composite composite= (Composite) parent;
 117                                 composite.layout(true);
 118                         }
 119
 120                         parent.setRedraw(true);
 121
 122                 } else {
 123                         StyledText styledText= getViewer().getTextWidget();
 124                         styledText.setFont(font);
 125                 }
 126         }
 127
 128         /**
 129          * Sets the initial partition for the underlying source viewer.
 130          *
 131          * @param partition the partition type
 132          */
 133         public void setStartingPartitionType(String partition) {
 134                 if (partition == null)
 135                         fPartition= IDocument.DEFAULT_CONTENT_TYPE;
 136                 else
 137                         fPartition= partition;
 138         }
 139
 140         /*
 141          * @see org.eclipse.jface.text.IInformationControl#setInformation(java.lang.String)
 142          */
 143         @Override
 144         public void setInformation(String content) {
 145                 super.setInformation(content);
 146                 IDocument doc= getViewer().getDocument();
 147                 if (doc == null)
 148                         return;
 149
 150                 // ensure that we can scroll enough
 151                 ensureScrollable();
 152
 153                 String start= null;
 154                 if (IJavaPartitions.JAVA_DOC.equals(fPartition)) {
 155                         start= "/**" + doc.getLegalLineDelimiters()[0]; //$NON-NLS-1$
 156                 } else if (IJavaPartitions.JAVA_MULTI_LINE_COMMENT.equals(fPartition)) {
 157                         start= "/*" + doc.getLegalLineDelimiters()[0]; //$NON-NLS-1$
 158                 }
 159                 if (start != null) {
 160                         try {
 161                                 doc.replace(0, 0, start);
 162                                 int startLen= start.length();
 163                                 getViewer().setDocument(doc, startLen, doc.getLength() - startLen);
 164                         } catch (BadLocationException e) {
 165                                 // impossible
 166                                 Assert.isTrue(false);
 167                         }
 168                 }
 169
 170                 getViewer().getTextWidget().setHorizontalPixel(fHorizontalScrollPixel);
 171         }
 172
 173         /**
 174          * Ensures that the control can be scrolled at least to
 175          * <code>fHorizontalScrollPixel</code> and adjusts <code>fMaxWidth</code>
 176          * accordingly.
 177          */
 178         private void ensureScrollable() {
 179                 IDocument doc= getViewer().getDocument();
 180                 if (doc == null)
 181                         return;
 182
 183                 StyledText widget= getViewer().getTextWidget();
 184                 if (widget == null || widget.isDisposed())
 185                         return;
 186
 187                 int last= doc.getNumberOfLines() - 1;
 188                 GC gc= new GC(widget);
 189                 gc.setFont(widget.getFont());
 190                 int maxWidth= 0;
 191                 String content= new String();
 192
 193                 try {
 194                         for (int i= 0; i <= last; i++) {
 195                                 IRegion line;
 196                                 line= doc.getLineInformation(i);
 197                                 content= doc.get(line.getOffset(), line.getLength());
 198                                 int width= gc.textExtent(content).x;
 199                                 if (width > maxWidth) {
 200                                         maxWidth= width;
 201                                 }
 202                         }
 203                 } catch (BadLocationException e) {
 204                         return;
 205                 } finally {
 206                         gc.dispose();
 207                 }
 208
 209                 // limit the size of the window to the maximum width minus scrolling,
 210                 // but never more than the configured max size (viewport size).
 211                 fMaxWidth= Math.max(0, Math.min(fMaxWidth, maxWidth - fHorizontalScrollPixel + 8));
 212         }
 213
 214         /*
 215          * @see org.eclipse.jdt.internal.ui.text.java.hover.SourceViewerInformationControl#hasContents()
 216          */
 217         @Override
 218         public boolean hasContents() {
 219                 return super.hasContents() && fMaxWidth > 0;
 220         }
 221
 222         /**
 223          * Sets the horizontal scroll index in pixels.
 224          *
 225          * @param scrollIndex the new horizontal scroll index
 226          */
 227         public void setHorizontalScrollPixel(int scrollIndex) {
 228                 scrollIndex= Math.max(0, scrollIndex);
 229                 fHorizontalScrollPixel= scrollIndex;
 230         }
 231
 232         public void generated_3096472255417592767(JavaChangeHover javachangehover) {
 233                 setStartingPartitionType(javachangehover.fPartition);
 234                 setHorizontalScrollPixel(javachangehover.fLastScrollIndex);
 235         }
 236 }