Exposing Qt's Q_ENUMS to QML

最新推荐文章于 2025-10-27 16:02:00 发布

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本文介绍了如何将Qt的枚举类型（Q_ENUMS）暴露给QML，并展示了通过一个具体的ColorMaker类实例来实现这一过程的方法。文章还提供了一个完整的代码示例，包括注册类型、使用属性和信号等。

转载：http://stackoverflow.com/questions/4461017/exposing-qts-q-enums-to-qml

Enum values can only be accessed as "ElementName.EnumValue", not "object.EnumValue". So, aVar.FirstValue won't work; you'll need to use MyClass.FirstValue instead (and to do this, you'll need to register MyClass with qmlRegisterType() and then import the registered module).

Also, enum values as not returned as strings since they are defined as integer values.

转载：http://www.tuicool.com/articles/rERbu2

class ColorMaker : public QObject
{
  Q_OBJECT
  Q_ENUMS(GenerateAlgorithm)
  Q_PROPERTY(QColor color READ color WRITE setColor NOTIFY colorChanged)
  Q_PROPERTY(QColor timeColor READ timeColor)

public:
  ColorMaker(QObject *parent = 0);
  ~ColorMaker();

  enum GenerateAlgorithm{
    RandomRGB,
    RandomRed,
    RandomGreen,
    RandomBlue,
    LinearIncrease
  };

  QColor color() const;
  void setColor(const QColor & color);
  QColor timeColor() const;

  Q_INVOKABLE GenerateAlgorithm algorithm() const;
  Q_INVOKABLE void setAlgorithm(GenerateAlgorithm algorithm);

signals:
  void colorChanged(const QColor & color);
  void currentTime(const QString &strTime);

public slots:
  void start();
  void stop();

protected:
  void timerEvent(QTimerEvent *e);

private:
  GenerateAlgorithm m_algorithm;
  QColor m_currentColor;
  int m_nColorTimer;
};

import QtQuick 2.0
import QtQuick.Controls 1.1
import an.qt.ColorMaker 1.0

Rectangle {
  width: 360;
  height: 360;
  Text {
    id: timeLabel;
    anchors.left: parent.left;
    anchors.leftMargin: 4;
    anchors.top: parent.top;
    anchors.topMargin: 4;
    font.pixelSize: 26;
  }
  ColorMaker {
    id: colorMaker;
    color: Qt.green;
  }

  Rectangle {
    id: colorRect;
    anchors.centerIn: parent;
    width: 200;
    height: 200;
    color: "blue";
  }

  Button {
    id: start;
    text: "start";
    anchors.left: parent.left;
    anchors.leftMargin: 4;
    anchors.bottom: parent.bottom;
    anchors.bottomMargin: 4;
    onClicked: {
      colorMaker.start();
    }
  }
  Button {
    id: stop;
    text: "stop";
    anchors.left: start.right;
    anchors.leftMargin: 4;
    anchors.bottom: start.bottom;
    onClicked: {
      colorMaker.stop();
    }
  }

  function changeAlgorithm(button, algorithm){
    switch(algorithm)
    {
    case 0:
      button.text = "RandomRGB";
      break;
    case 1:
      button.text = "RandomRed";
      break;
    case 2:
      button.text = "RandomGreen";
      break;
    case 3:
      button.text = "RandomBlue";
      break;
    case 4:
      button.text = "LinearIncrease";
      break;
    }
  }

  Button {
    id: colorAlgorithm;
    text: "RandomRGB";
    anchors.left: stop.right;
    anchors.leftMargin: 4;
    anchors.bottom: start.bottom;
    onClicked: {
      var algorithm = (colorMaker.algorithm() + 1) % 5;
      changeAlgorithm(colorAlgorithm, algorithm);
      colorMaker.setAlgorithm(algorithm);
    }
  }

  Button {
    id: quit;
    text: "quit";
    anchors.left: colorAlgorithm.right;
    anchors.leftMargin: 4;
    anchors.bottom: start.bottom;
    onClicked: {
      Qt.quit();
    }
  }

  Component.onCompleted: {
    colorMaker.color = Qt.rgba(0,180,120, 255);
    colorMaker.setAlgorithm(ColorMaker.LinearIncrease);
    changeAlgorithm(colorAlgorithm, colorMaker.algorithm());
  }

  Connections {
    target: colorMaker;
    onCurrentTime:{
      timeLabel.text = strTime;
      timeLabel.color = colorMaker.timeColor;
    }
  }

  Connections {
    target: colorMaker;
    onColorChanged:{
      colorRect.color = color;
    }
  }
}