src/qt/bitcoinamountfield.cpp

   1 // Copyright (c) 2011-2015 The Bitcoin Core developers
   2 // Distributed under the MIT software license, see the accompanying
   3 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
   4
   5 #include "bitcoinamountfield.h"
   6
   7 #include "bitcoinunits.h"
   8 #include "guiconstants.h"
   9 #include "qvaluecombobox.h"
  10
  11 #include <QApplication>
  12 #include <QAbstractSpinBox>
  13 #include <QHBoxLayout>
  14 #include <QKeyEvent>
  15 #include <QLineEdit>
  16
  17 /** QSpinBox that uses fixed-point numbers internally and uses our own
  18  * formatting/parsing functions.
  19  */
  20 class AmountSpinBox: public QAbstractSpinBox
  21 {
  22     Q_OBJECT
  23
  24 public:
  25     explicit AmountSpinBox(QWidget *parent):
  26         QAbstractSpinBox(parent),
  27         currentUnit(BitcoinUnits::BTC),
  28         singleStep(100000) // satoshis
  29     {
  30         setAlignment(Qt::AlignRight);
  31
  32         connect(lineEdit(), SIGNAL(textEdited(QString)), this, SIGNAL(valueChanged()));
  33     }
  34
  35     QValidator::State validate(QString &text, int &pos) const
  36     {
  37         if(text.isEmpty())
  38             return QValidator::Intermediate;
  39         bool valid = false;
  40         parse(text, &valid);
  41         /* Make sure we return Intermediate so that fixup() is called on defocus */
  42         return valid ? QValidator::Intermediate : QValidator::Invalid;
  43     }
  44
  45     void fixup(QString &input) const
  46     {
  47         bool valid = false;
  48         CAmount val = parse(input, &valid);
  49         if(valid)
  50         {
  51             input = BitcoinUnits::format(currentUnit, val, false, BitcoinUnits::separatorAlways);
  52             lineEdit()->setText(input);
  53         }
  54     }
  55
  56     CAmount value(bool *valid_out=0) const
  57     {
  58         return parse(text(), valid_out);
  59     }
  60
  61     void setValue(const CAmount& value)
  62     {
  63         lineEdit()->setText(BitcoinUnits::format(currentUnit, value, false, BitcoinUnits::separatorAlways));
  64         Q_EMIT valueChanged();
  65     }
  66
  67     void stepBy(int steps)
  68     {
  69         bool valid = false;
  70         CAmount val = value(&valid);
  71         val = val + steps * singleStep;
  72         val = qMin(qMax(val, CAmount(0)), BitcoinUnits::maxMoney());
  73         setValue(val);
  74     }
  75
  76     void setDisplayUnit(int unit)
  77     {
  78         bool valid = false;
  79         CAmount val = value(&valid);
  80
  81         currentUnit = unit;
  82
  83         if(valid)
  84             setValue(val);
  85         else
  86             clear();
  87     }
  88
  89     void setSingleStep(const CAmount& step)
  90     {
  91         singleStep = step;
  92     }
  93
  94     QSize minimumSizeHint() const
  95     {
  96         if(cachedMinimumSizeHint.isEmpty())
  97         {
  98             ensurePolished();
  99
 100             const QFontMetrics fm(fontMetrics());
 101             int h = lineEdit()->minimumSizeHint().height();
 102             int w = fm.width(BitcoinUnits::format(BitcoinUnits::BTC, BitcoinUnits::maxMoney(), false, BitcoinUnits::separatorAlways));
 103             w += 2; // cursor blinking space
 104
 105             QStyleOptionSpinBox opt;
 106             initStyleOption(&opt);
 107             QSize hint(w, h);
 108             QSize extra(35, 6);
 109             opt.rect.setSize(hint + extra);
 110             extra += hint - style()->subControlRect(QStyle::CC_SpinBox, &opt,
 111                                                     QStyle::SC_SpinBoxEditField, this).size();
 112             // get closer to final result by repeating the calculation
 113             opt.rect.setSize(hint + extra);
 114             extra += hint - style()->subControlRect(QStyle::CC_SpinBox, &opt,
 115                                                     QStyle::SC_SpinBoxEditField, this).size();
 116             hint += extra;
 117             hint.setHeight(h);
 118
 119             opt.rect = rect();
 120
 121             cachedMinimumSizeHint = style()->sizeFromContents(QStyle::CT_SpinBox, &opt, hint, this)
 122                                     .expandedTo(QApplication::globalStrut());
 123         }
 124         return cachedMinimumSizeHint;
 125     }
 126
 127 private:
 128     int currentUnit;
 129     CAmount singleStep;
 130     mutable QSize cachedMinimumSizeHint;
 131
 132     /**
 133      * Parse a string into a number of base monetary units and
 134      * return validity.
 135      * @note Must return 0 if !valid.
 136      */
 137     CAmount parse(const QString &text, bool *valid_out=0) const
 138     {
 139         CAmount val = 0;
 140         bool valid = BitcoinUnits::parse(currentUnit, text, &val);
 141         if(valid)
 142         {
 143             if(val < 0 || val > BitcoinUnits::maxMoney())
 144                 valid = false;
 145         }
 146         if(valid_out)
 147             *valid_out = valid;
 148         return valid ? val : 0;
 149     }
 150
 151 protected:
 152     bool event(QEvent *event)
 153     {
 154         if (event->type() == QEvent::KeyPress || event->type() == QEvent::KeyRelease)
 155         {
 156             QKeyEvent *keyEvent = static_cast<QKeyEvent *>(event);
 157             if (keyEvent->key() == Qt::Key_Comma)
 158             {
 159                 // Translate a comma into a period
 160                 QKeyEvent periodKeyEvent(event->type(), Qt::Key_Period, keyEvent->modifiers(), ".", keyEvent->isAutoRepeat(), keyEvent->count());
 161                 return QAbstractSpinBox::event(&periodKeyEvent);
 162             }
 163         }
 164         return QAbstractSpinBox::event(event);
 165     }
 166
 167     StepEnabled stepEnabled() const
 168     {
 169         if (isReadOnly()) // Disable steps when AmountSpinBox is read-only
 170             return StepNone;
 171         if (text().isEmpty()) // Allow step-up with empty field
 172             return StepUpEnabled;
 173
 174         StepEnabled rv = 0;
 175         bool valid = false;
 176         CAmount val = value(&valid);
 177         if(valid)
 178         {
 179             if(val > 0)
 180                 rv |= StepDownEnabled;
 181             if(val < BitcoinUnits::maxMoney())
 182                 rv |= StepUpEnabled;
 183         }
 184         return rv;
 185     }
 186
 187 Q_SIGNALS:
 188     void valueChanged();
 189 };
 190
 191 #include "bitcoinamountfield.moc"
 192
 193 BitcoinAmountField::BitcoinAmountField(QWidget *parent) :
 194     QWidget(parent),
 195     amount(0)
 196 {
 197     amount = new AmountSpinBox(this);
 198     amount->setLocale(QLocale::c());
 199     amount->installEventFilter(this);
 200     amount->setMaximumWidth(170);
 201
 202     QHBoxLayout *layout = new QHBoxLayout(this);
 203     layout->addWidget(amount);
 204     unit = new QValueComboBox(this);
 205     unit->setModel(new BitcoinUnits(this));
 206     layout->addWidget(unit);
 207     layout->addStretch(1);
 208     layout->setContentsMargins(0,0,0,0);
 209
 210     setLayout(layout);
 211
 212     setFocusPolicy(Qt::TabFocus);
 213     setFocusProxy(amount);
 214
 215     // If one if the widgets changes, the combined content changes as well
 216     connect(amount, SIGNAL(valueChanged()), this, SIGNAL(valueChanged()));
 217     connect(unit, SIGNAL(currentIndexChanged(int)), this, SLOT(unitChanged(int)));
 218
 219     // Set default based on configuration
 220     unitChanged(unit->currentIndex());
 221 }
 222
 223 void BitcoinAmountField::clear()
 224 {
 225     amount->clear();
 226     unit->setCurrentIndex(0);
 227 }
 228
 229 void BitcoinAmountField::setEnabled(bool fEnabled)
 230 {
 231     amount->setEnabled(fEnabled);
 232     unit->setEnabled(fEnabled);
 233 }
 234
 235 bool BitcoinAmountField::validate()
 236 {
 237     bool valid = false;
 238     value(&valid);
 239     setValid(valid);
 240     return valid;
 241 }
 242
 243 void BitcoinAmountField::setValid(bool valid)
 244 {
 245     if (valid)
 246         amount->setStyleSheet("");
 247     else
 248         amount->setStyleSheet(STYLE_INVALID);
 249 }
 250
 251 bool BitcoinAmountField::eventFilter(QObject *object, QEvent *event)
 252 {
 253     if (event->type() == QEvent::FocusIn)
 254     {
 255         // Clear invalid flag on focus
 256         setValid(true);
 257     }
 258     return QWidget::eventFilter(object, event);
 259 }
 260
 261 QWidget *BitcoinAmountField::setupTabChain(QWidget *prev)
 262 {
 263     QWidget::setTabOrder(prev, amount);
 264     QWidget::setTabOrder(amount, unit);
 265     return unit;
 266 }
 267
 268 CAmount BitcoinAmountField::value(bool *valid_out) const
 269 {
 270     return amount->value(valid_out);
 271 }
 272
 273 void BitcoinAmountField::setValue(const CAmount& value)
 274 {
 275     amount->setValue(value);
 276 }
 277
 278 void BitcoinAmountField::setReadOnly(bool fReadOnly)
 279 {
 280     amount->setReadOnly(fReadOnly);
 281 }
 282
 283 void BitcoinAmountField::unitChanged(int idx)
 284 {
 285     // Use description tooltip for current unit for the combobox
 286     unit->setToolTip(unit->itemData(idx, Qt::ToolTipRole).toString());
 287
 288     // Determine new unit ID
 289     int newUnit = unit->itemData(idx, BitcoinUnits::UnitRole).toInt();
 290
 291     amount->setDisplayUnit(newUnit);
 292 }
 293
 294 void BitcoinAmountField::setDisplayUnit(int newUnit)
 295 {
 296     unit->setValue(newUnit);
 297 }
 298
 299 void BitcoinAmountField::setSingleStep(const CAmount& step)
 300 {
 301     amount->setSingleStep(step);
 302 }