QGIS API Documentation  3.6.0-Noosa (5873452)
qgslayoutitemundocommand.cpp
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1 /***************************************************************************
2  qgslayoutitemundocommand.cpp
3  ------------------------
4  begin : July 2017
5  copyright : (C) 2017 by Nyall Dawson
6  email : nyall dot dawson at gmail dot com
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 
19 #include "qgslayoutitem.h"
20 #include "qgsreadwritecontext.h"
21 #include "qgslayout.h"
22 #include "qgsproject.h"
23 #include "qgslayoutundostack.h"
24 
26 QgsLayoutItemUndoCommand::QgsLayoutItemUndoCommand( QgsLayoutItem *item, const QString &text, int id, QUndoCommand *parent )
27  : QgsAbstractLayoutUndoCommand( text, id, parent )
28  , mItemUuid( item->uuid() )
29  , mLayout( item->layout() )
30  , mItemType( item->type() )
31 {
32 
33 }
34 
35 bool QgsLayoutItemUndoCommand::mergeWith( const QUndoCommand *command )
36 {
37  if ( command->id() == 0 )
38  return false;
39 
40  const QgsLayoutItemUndoCommand *c = dynamic_cast<const QgsLayoutItemUndoCommand *>( command );
41  if ( !c )
42  {
43  return false;
44  }
45  if ( c->itemUuid() != itemUuid() )
46  return false;
47 
48  setAfterState( c->afterState() );
49  return true;
50 }
51 
52 void QgsLayoutItemUndoCommand::saveState( QDomDocument &stateDoc ) const
53 {
54  stateDoc.clear();
55  QDomElement documentElement = stateDoc.createElement( QStringLiteral( "ItemState" ) );
56 
57  QgsLayoutItem *item = mLayout->itemByUuid( mItemUuid );
58  Q_ASSERT_X( item, "QgsLayoutItemUndoCommand::saveState", "could not retrieve item for saving state" );
59 
60  item->writeXml( documentElement, stateDoc, QgsReadWriteContext() );
61  stateDoc.appendChild( documentElement );
62 }
63 
64 void QgsLayoutItemUndoCommand::restoreState( QDomDocument &stateDoc )
65 {
66  // find item by uuid...
67  QgsLayoutItem *item = mLayout->itemByUuid( mItemUuid );
68  if ( !item )
69  {
70  // uh oh - it's been deleted! we need to create a new instance
71  item = recreateItem( mItemType, mLayout );
72  }
73 
74  item->readXml( stateDoc.documentElement().firstChild().toElement(), stateDoc, QgsReadWriteContext() );
75  item->finalizeRestoreFromXml();
76  mLayout->project()->setDirty( true );
77  mLayout->undoStack()->notifyUndoRedoOccurred( item );
78 }
79 
80 QgsLayoutItem *QgsLayoutItemUndoCommand::recreateItem( int itemType, QgsLayout *layout )
81 {
82  QgsLayoutItem *item = QgsApplication::layoutItemRegistry()->createItem( itemType, layout );
83  mLayout->addLayoutItemPrivate( item );
84  return item;
85 }
86 
87 QString QgsLayoutItemUndoCommand::itemUuid() const
88 {
89  return mItemUuid;
90 }
91 
92 QgsLayout *QgsLayoutItemUndoCommand::layout() const
93 {
94  return mLayout;
95 }
96 
97 
98 //
99 // QgsLayoutItemDeleteUndoCommand
100 //
101 
102 QgsLayoutItemDeleteUndoCommand::QgsLayoutItemDeleteUndoCommand( QgsLayoutItem *item, const QString &text, int id, QUndoCommand *parent )
103  : QgsLayoutItemUndoCommand( item, text, id, parent )
104 {
105  saveBeforeState();
106 }
107 
108 bool QgsLayoutItemDeleteUndoCommand::mergeWith( const QUndoCommand * )
109 {
110  return false;
111 }
112 
113 void QgsLayoutItemDeleteUndoCommand::redo()
114 {
115  if ( mFirstRun )
116  {
117  mFirstRun = false;
118  return;
119  }
120 
121  QgsLayoutItem *item = layout()->itemByUuid( itemUuid() );
122  //Q_ASSERT_X( item, "QgsLayoutItemDeleteUndoCommand::redo", "could not find item to re-delete!" );
123 
124  layout()->undoStack()->blockCommands( true );
125  if ( item )
126  layout()->removeLayoutItemPrivate( item );
127  layout()->undoStack()->blockCommands( false );
128 }
129 
130 QgsLayoutItemAddItemCommand::QgsLayoutItemAddItemCommand( QgsLayoutItem *item, const QString &text, int id, QUndoCommand *parent )
131  : QgsLayoutItemUndoCommand( item, text, id, parent )
132 {
133  saveAfterState();
134 }
135 
136 bool QgsLayoutItemAddItemCommand::containsChange() const
137 {
138  return true;
139 }
140 
141 bool QgsLayoutItemAddItemCommand::mergeWith( const QUndoCommand * )
142 {
143  return false;
144 }
145 
146 void QgsLayoutItemAddItemCommand::undo()
147 {
148  if ( mFirstRun )
149  {
150  mFirstRun = false;
151  return;
152  }
153 
154  QgsLayoutItem *item = layout()->itemByUuid( itemUuid() );
155  if ( item )
156  {
157  layout()->removeLayoutItemPrivate( item );
158  }
159 }
160 
161 
The class is used as a container of context for various read/write operations on other objects...
QgsLayoutItem * createItem(int type, QgsLayout *layout) const
Creates a new instance of a layout item given the item type, and target layout.
Base class for graphical items within a QgsLayout.
Base class for commands to undo/redo layout and layout object changes.
QgsLayoutUndoStack * undoStack()
Returns a pointer to the layout&#39;s undo stack, which manages undo/redo states for the layout and it&#39;s ...
Definition: qgslayout.cpp:683
QgsLayoutItem * itemByUuid(const QString &uuid, bool includeTemplateUuids=false) const
Returns the layout item with matching uuid unique identifier, or a nullptr if a matching item could n...
Definition: qgslayout.cpp:236
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
bool writeXml(QDomElement &parentElement, QDomDocument &document, const QgsReadWriteContext &context) const
Stores the item state in a DOM element.
static QgsLayoutItemRegistry * layoutItemRegistry()
Returns the application&#39;s layout item registry, used for layout item types.
const QgsLayout * layout() const
Returns the layout the object is attached to.
QPointer< QgsLayout > mLayout
Base class for layouts, which can contain items such as maps, labels, scalebars, etc.
Definition: qgslayout.h:49
void blockCommands(bool blocked)
Sets whether undo commands for the layout should be temporarily blocked.
bool readXml(const QDomElement &itemElement, const QDomDocument &document, const QgsReadWriteContext &context)
Sets the item state from a DOM element.
virtual void finalizeRestoreFromXml()
Called after all pending items have been restored from XML.