QGIS API Documentation  3.37.0-Master (a5b4d9743e8)
qgshtmlannotation.cpp
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1 /***************************************************************************
2  qgshtmlannotation.h
3  ------------------------
4  begin : February 26, 2010
5  copyright : (C) 2010 by Marco Hugentobler
6  email : marco dot hugentobler at hugis dot net
7  ***************************************************************************/
8 
9 /***************************************************************************
10  * *
11  * This program is free software; you can redistribute it and/or modify *
12  * it under the terms of the GNU General Public License as published by *
13  * the Free Software Foundation; either version 2 of the License, or *
14  * (at your option) any later version. *
15  * *
16  ***************************************************************************/
17 
18 #include "qgshtmlannotation.h"
19 #include "qgsfeature.h"
20 #include "qgsfeatureiterator.h"
21 #include "qgslogger.h"
22 #include "qgsproject.h"
23 #include "qgsvectorlayer.h"
24 #include "qgsexpression.h"
26 #include "qgswebpage.h"
27 #include "qgswebframe.h"
29 #include "qgsrendercontext.h"
30 
31 #include <QDomElement>
32 #include <QDir>
33 #include <QFile>
34 #include <QFileInfo>
35 #include <QGraphicsProxyWidget>
36 #include <QPainter>
37 #include <QSettings>
38 #include <QWidget>
39 #include <QTextStream>
40 
42  : QgsAnnotation( parent )
43 {
44  mWebPage = new QgsWebPage();
45  mWebPage->mainFrame()->setScrollBarPolicy( Qt::Horizontal, Qt::ScrollBarAlwaysOff );
46  mWebPage->mainFrame()->setScrollBarPolicy( Qt::Vertical, Qt::ScrollBarAlwaysOff );
47  mWebPage->setNetworkAccessManager( QgsNetworkAccessManager::instance() );
48 
49  // Make QWebPage transparent so that the background color of the annotation frame is used
50  QPalette palette = mWebPage->palette();
51  palette.setBrush( QPalette::Base, Qt::transparent );
52  mWebPage->setPalette( palette );
53 
54  connect( mWebPage->mainFrame(), &QWebFrame::javaScriptWindowObjectCleared, this, &QgsHtmlAnnotation::javascript );
55 }
56 
58 {
59  std::unique_ptr< QgsHtmlAnnotation > c( new QgsHtmlAnnotation() );
60  copyCommonProperties( c.get() );
61  c->setSourceFile( mHtmlFile );
62  return c.release();
63 }
64 
65 void QgsHtmlAnnotation::setSourceFile( const QString &htmlFile )
66 {
67  QFile file( htmlFile );
68  mHtmlFile = htmlFile;
69  if ( !file.open( QIODevice::ReadOnly | QIODevice::Text ) )
70  {
71  mHtmlSource.clear();
72  }
73  else
74  {
75  QTextStream in( &file );
76 #if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
77  in.setCodec( "UTF-8" );
78 #endif
79  mHtmlSource = in.readAll();
80  }
81 
82  file.close();
84  emit appearanceChanged();
85 }
86 
87 void QgsHtmlAnnotation::setHtmlSource( const QString &htmlSource )
88 {
89  mHtmlFile.clear();
90  mHtmlSource = htmlSource;
92  emit appearanceChanged();
93 }
94 
95 void QgsHtmlAnnotation::renderAnnotation( QgsRenderContext &context, QSizeF size ) const
96 {
97  if ( !context.painter() || ( context.feedback() && context.feedback()->isCanceled() ) )
98  {
99  return;
100  }
101 
102  // scale painter back to 96 dpi, so layout prints match screen rendering
103  const QgsScopedQPainterState painterState( context.painter() );
104  const double scaleFactor = context.painter()->device()->logicalDpiX() / 96.0;
105  context.painter()->scale( scaleFactor, scaleFactor );
106  size /= scaleFactor;
107 
108  mWebPage->setViewportSize( size.toSize() );
109  mWebPage->mainFrame()->render( context.painter() );
110 }
111 
113 {
114  if ( mWebPage )
115  {
116  const QSizeF widgetMinSize = QSizeF( 0, 0 ); // mWebPage->minimumSize();
117  return QSizeF( contentsMargin().left() + contentsMargin().right() + widgetMinSize.width(),
118  contentsMargin().top() + contentsMargin().bottom() + widgetMinSize.height() );
119  }
120  else
121  {
122  return QSizeF( 0, 0 );
123  }
124 }
125 
126 void QgsHtmlAnnotation::writeXml( QDomElement &elem, QDomDocument &doc, const QgsReadWriteContext &context ) const
127 {
128  QDomElement formAnnotationElem = doc.createElement( QStringLiteral( "HtmlAnnotationItem" ) );
129  if ( !mHtmlFile.isEmpty() )
130  {
131  formAnnotationElem.setAttribute( QStringLiteral( "htmlfile" ), sourceFile() );
132  }
133  else
134  {
135  formAnnotationElem.setAttribute( QStringLiteral( "htmlsource" ), mHtmlSource );
136  }
137 
138  _writeXml( formAnnotationElem, doc, context );
139  elem.appendChild( formAnnotationElem );
140 }
141 
142 void QgsHtmlAnnotation::readXml( const QDomElement &itemElem, const QgsReadWriteContext &context )
143 {
144  const QDomElement annotationElem = itemElem.firstChildElement( QStringLiteral( "AnnotationItem" ) );
145  if ( !annotationElem.isNull() )
146  {
147  _readXml( annotationElem, context );
148  }
149 
150  // upgrade old layer
151  if ( !mapLayer() && itemElem.hasAttribute( QStringLiteral( "vectorLayer" ) ) )
152  {
153  setMapLayer( QgsProject::instance()->mapLayer( itemElem.attribute( QStringLiteral( "vectorLayer" ) ) ) );
154  }
155 
156  if ( mWebPage )
157  {
158  mHtmlFile = itemElem.attribute( QStringLiteral( "htmlfile" ), QString() );
159  if ( !mHtmlFile.isEmpty() )
160  {
161  setSourceFile( mHtmlFile );
162  }
163  else
164  {
165  setHtmlSource( itemElem.attribute( QStringLiteral( "htmlsource" ), QString() ) );
166  }
167  }
168 }
169 
171 {
173  QString newText;
174  QgsVectorLayer *vectorLayer = qobject_cast< QgsVectorLayer * >( mapLayer() );
175  if ( feature.isValid() && vectorLayer )
176  {
178  context.setFeature( feature );
179  newText = QgsExpression::replaceExpressionText( mHtmlSource, &context );
180  }
181  else
182  {
183  newText = mHtmlSource;
184  }
185  mWebPage->mainFrame()->setHtml( newText );
186  emit appearanceChanged();
187 }
188 
189 void QgsHtmlAnnotation::javascript()
190 {
191  QWebFrame *frame = mWebPage->mainFrame();
192  frame->addToJavaScriptWindowObject( QStringLiteral( "layer" ), mapLayer() );
193 }
The QWebFrame class is a collection of stubs to mimic the API of a QWebFrame on systems where QtWebki...
Definition: qgswebframe.h:38
Abstract base class for annotation items which are drawn over a map.
Definition: qgsannotation.h:53
void appearanceChanged()
Emitted whenever the annotation's appearance changes.
QgsMapLayer * mapLayer() const
Returns the map layer associated with the annotation.
QgsMargins contentsMargin() const
Returns the margins (in millimeters) between the outside of the frame and the annotation content.
void _writeXml(QDomElement &itemElem, QDomDocument &doc, const QgsReadWriteContext &context) const
Writes common annotation properties to a DOM element.
virtual void setAssociatedFeature(const QgsFeature &feature)
Sets the feature associated with the annotation.
QgsFeature associatedFeature() const
Returns the feature associated with the annotation, or an invalid feature if none has been set.
void _readXml(const QDomElement &annotationElem, const QgsReadWriteContext &context)
Reads common annotation properties from a DOM element.
void copyCommonProperties(QgsAnnotation *target) const
Copies common annotation properties to the targe annotation.
void setMapLayer(QgsMapLayer *layer)
Sets the map layer associated with the annotation.
static QList< QgsExpressionContextScope * > globalProjectLayerScopes(const QgsMapLayer *layer)
Creates a list of three scopes: global, layer's project and layer.
Expression contexts are used to encapsulate the parameters around which a QgsExpression should be eva...
void setFeature(const QgsFeature &feature)
Convenience function for setting a feature for the context.
static QString replaceExpressionText(const QString &action, const QgsExpressionContext *context, const QgsDistanceArea *distanceArea=nullptr)
This function replaces each expression between [% and %] in the string with the result of its evaluat...
The feature class encapsulates a single feature including its unique ID, geometry and a list of field...
Definition: qgsfeature.h:56
bool isValid() const
Returns the validity of this feature.
Definition: qgsfeature.cpp:216
bool isCanceled() const
Tells whether the operation has been canceled already.
Definition: qgsfeedback.h:53
An annotation item that embeds HTML content.
QgsHtmlAnnotation * clone() const override
Clones the annotation, returning a new copy of the annotation reflecting the annotation's current sta...
QString htmlSource() const
Returns html source text.
QgsHtmlAnnotation(QObject *parent=nullptr)
Constructor for QgsHtmlAnnotation.
void writeXml(QDomElement &elem, QDomDocument &doc, const QgsReadWriteContext &context) const override
Writes the annotation state to a DOM element.
void readXml(const QDomElement &itemElem, const QgsReadWriteContext &context) override
Restores the annotation's state from a DOM element.
void setSourceFile(const QString &htmlFile)
Sets the file path for the source HTML file.
QSizeF minimumFrameSize() const override
Returns the minimum frame size for the annotation.
void setHtmlSource(const QString &htmlSource)
Sets the html source directly (not coming from a file)
void setAssociatedFeature(const QgsFeature &feature) override
Sets the feature associated with the annotation.
void renderAnnotation(QgsRenderContext &context, QSizeF size) const override
Renders the annotation's contents to a target /a context at the specified /a size.
QString sourceFile() const
Returns the file path for the source HTML file.
static QgsNetworkAccessManager * instance(Qt::ConnectionType connectionType=Qt::BlockingQueuedConnection)
Returns a pointer to the active QgsNetworkAccessManager for the current thread.
static QgsProject * instance()
Returns the QgsProject singleton instance.
Definition: qgsproject.cpp:481
The class is used as a container of context for various read/write operations on other objects.
Contains information about the context of a rendering operation.
QPainter * painter()
Returns the destination QPainter for the render operation.
QgsFeedback * feedback() const
Returns the feedback object that can be queried regularly during rendering to check if rendering shou...
Scoped object for saving and restoring a QPainter object's state.
Represents a vector layer which manages a vector based data sets.
QWebPage subclass which redirects JavaScript errors and console output to the QGIS message log.
Definition: qgswebpage.h:217
As part of the API refactoring and improvements which landed in the Processing API was substantially reworked from the x version This was done in order to allow much of the underlying Processing framework to be ported into c