1 /*
2  * Copyright (C) 2001-2015 Klaralvdalens Datakonsult AB.  All rights reserved.
3  *
4  * This file is part of the KD Chart library.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of
9  * the License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program.  If not, see <https://www.gnu.org/licenses/>.
18  */
19 
20 #ifndef KCHARTABSTRACTAREAWIDGET_H
21 #define KCHARTABSTRACTAREAWIDGET_H
22 
23 #include <QWidget>
24 #include <QPaintEvent>
25 #include <QPainter>
26 #include <QRect>
27 
28 #include "KChartAbstractAreaBase.h"
29 
30 namespace KChart {
31 
32 
33 /**
34   * @class AbstractAreaWidget KChartAbstractArea.h
35   * @brief An area in the chart with a background, a frame, etc.
36   *
37   * AbstractAreaWidget is the base for all widget classes that have
38   * a set of background attributes and frame attributes, such as
39   * KChart::Chart and KChart::Legend.
40   */
41 class KCHART_EXPORT AbstractAreaWidget : public QWidget, public AbstractAreaBase
42 {
43     Q_OBJECT
44 
45     Q_DISABLE_COPY( AbstractAreaWidget )
46     KCHART_DECLARE_PRIVATE_DERIVED_QWIDGET( AbstractAreaWidget )
47 
48 public:
49     explicit AbstractAreaWidget( QWidget* parent = nullptr );
50 
51     /**
52       * @brief Draws the background and frame, then calls paint().
53       *
54       * In most cases there is no need to overwrite this method in a derived
55       * class, but you would overwrite paint() instead.
56       * @sa paint
57       */
58     void paintEvent( QPaintEvent* event ) override;
59 
60     /**
61       * @brief Draws the background and frame, then calls paint().
62       *
63       * In most cases there is no need to overwrite this method in a derived
64       * class, but you would overwrite paint() instead.
65       */
66     virtual void paintIntoRect( QPainter& painter, const QRect& rect );
67 
68     /**
69       * Overwrite this to paint the inner contents of your widget.
70       *
71       * @note When overriding this method, please let your widget draw
72       * itself at the top/left corner of the painter.  You should call rect()
73       * (or width(), height(), resp.) to find the drawable area's size:
74       * While the paint() method is being executed the frame of the widget
75       * is outside of its rect(), so you can use all of rect() for
76       * your custom drawing!
77       * @sa paint, paintIntoRect
78       */
79     virtual void paint( QPainter* painter ) = 0;
80 
81     /**
82       * Call paintAll, if you want the background and the frame to be drawn
83       * before the normal paint() is invoked automatically.
84       */
85     void paintAll( QPainter& painter );
86 
87     /**
88       * Call this to trigger an unconditional re-building of the widget's internals.
89       */
90     virtual void forceRebuild();
91 
92     /**
93       * Call this to trigger an conditional re-building of the widget's internals.
94       *
95       * e.g. AbstractAreaWidget call this, before calling layout()->setGeometry()
96       */
97     virtual void needSizeHint();
98     virtual void resizeLayout( const QSize& );
99 
100 Q_SIGNALS:
101     void positionChanged( AbstractAreaWidget * );
102 
103 protected:
104     virtual ~AbstractAreaWidget() ;
105     QRect areaGeometry() const override;
106     void positionHasChanged() override;
107 };
108 
109 }
110 #endif // KCHARTABSTRACTAREAWIDGET_H
111