1/*
2 * This file is part of KQuickCharts
3 * SPDX-FileCopyrightText: 2019 Arjen Hiemstra <ahiemstra@heimr.nl>
4 *
5 * SPDX-License-Identifier: LGPL-2.1-only OR LGPL-3.0-only OR LicenseRef-KDE-Accepted-LGPL
6 */
7
8#ifndef RANGEGROUP_H
9#define RANGEGROUP_H
10
11#include <functional>
12
13#include <QObject>
14#include <qqmlregistration.h>
15
16#include "quickcharts_export.h"
17
18class ChartDataSource;
19
20/*
21 * An object that can be used as a grouped property to provide a value range for charts.
22 *
23 */
24class QUICKCHARTS_EXPORT RangeGroup : public QObject
25{
26 Q_OBJECT
27 QML_NAMED_ELEMENT(Range)
28 QML_UNCREATABLE("Grouped Property")
29
30public:
31 struct RangeResult {
32 qreal start = 0.0;
33 qreal end = 0.0;
34 qreal distance = 0.0;
35 };
36
37 explicit RangeGroup(QObject *parent = nullptr);
38
39 /**
40 * The start of this range.
41 *
42 * The default is 0.
43 */
44 Q_PROPERTY(qreal from READ from WRITE setFrom NOTIFY fromChanged)
45 qreal from() const;
46 void setFrom(qreal from);
47 Q_SIGNAL void fromChanged();
48 /**
49 * The end of this range.
50 *
51 * The default is 100.
52 */
53 Q_PROPERTY(qreal to READ to WRITE setTo NOTIFY toChanged)
54 qreal to() const;
55 void setTo(qreal to);
56 Q_SIGNAL void toChanged();
57 /**
58 * Whether to determine the range based on values of a chart.
59 *
60 * If true (the default), `from` and `to` are ignored and instead calculated
61 * from the minimum and maximum values of a chart's valueSources.
62 */
63 Q_PROPERTY(bool automatic READ automatic WRITE setAutomatic NOTIFY automaticChanged)
64 bool automatic() const;
65 void setAutomatic(bool newAutomatic);
66 Q_SIGNAL void automaticChanged();
67 /**
68 * The distance between from and to.
69 */
70 Q_PROPERTY(qreal distance READ distance NOTIFY rangeChanged)
71 qreal distance() const;
72 /**
73 * The minimum size of the range.
74 *
75 * This is mostly relevant when automatic is true. Setting this value will
76 * ensure that the range will never be smaller than this value. The default
77 * is `std::numeric_limits<qreal>::min`, which means minimum is disabled.
78 */
79 Q_PROPERTY(qreal minimum READ minimum WRITE setMinimum NOTIFY minimumChanged)
80 qreal minimum() const;
81 void setMinimum(qreal newMinimum);
82 Q_SIGNAL void minimumChanged();
83 /**
84 * The amount with which the range increases.
85 *
86 * The total range will be limited to a multiple of this value. This is
87 * mostly useful when automatic is true. The default is 0.0, which means do
88 * not limit the range increment.
89 */
90 Q_PROPERTY(qreal increment READ increment WRITE setIncrement NOTIFY incrementChanged)
91 qreal increment() const;
92 void setIncrement(qreal newIncrement);
93 Q_SIGNAL void incrementChanged();
94
95 bool isValid() const;
96
97 Q_SIGNAL void rangeChanged();
98
99 RangeResult calculateRange(const QList<ChartDataSource *> &sources,
100 std::function<qreal(ChartDataSource *)> minimumCallback,
101 std::function<qreal(ChartDataSource *)> maximumCallback);
102
103private:
104 qreal m_from = 0.0;
105 qreal m_to = 100.0;
106 bool m_automatic = true;
107 qreal m_minimum = std::numeric_limits<qreal>::min();
108 qreal m_increment = 0.0;
109};
110
111#endif // RANGEGROUP_H
112

source code of kquickcharts/src/RangeGroup.h