Change the return type of model->data() function from QVariant to custom type
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Hey guys,
i have written my custom implementation of QAbstractTableModel. Of course i've implemented the virtual function model->data()
QVariant MAVHilStateModel::data(const QModelIndex &index, int role) const { if(index.isValid()) return QVariant(); if (index.row() >= hil_state_list.size()) return QVariant(); qDebug() << hil_state_list.at(index.row()); if (role == Qt::DisplayRole) return hil_state_list.at(index.row()); else return QVariant(); }Now i get the error message on the line where i want to return a custom type
return hil_state_list.at(index.row())Error:
MAVHilStateModel.cpp:47:12: error: conversion function from '__mavlink_hil_state_t *const' to 'QVariant' invokes a deleted function qvariant.h:497:12: note: 'QVariant' has been explicitly marked deleted hereThe custom type is defined in a third party library here:
// Macro to define packed structures #ifdef __GNUC__ #define MAVPACKED( __Declaration__ ) __Declaration__ __attribute__((packed)) #else #define MAVPACKED( __Declaration__ ) __pragma( pack(push, 1) ) __Declaration__ __pragma( pack(pop) ) #endif MAVPACKED( typedef struct __mavlink_hil_state_t { uint64_t time_usec; /*< [us] Timestamp (UNIX Epoch time or time since system boot). The receiving end can infer timestamp format (since 1.1.1970 or since system boot) by checking for the magnitude the number.*/ float roll; /*< [rad] Roll angle*/ float pitch; /*< [rad] Pitch angle*/ float yaw; /*< [rad] Yaw angle*/ float rollspeed; /*< [rad/s] Body frame roll / phi angular speed*/ float pitchspeed; /*< [rad/s] Body frame pitch / theta angular speed*/ float yawspeed; /*< [rad/s] Body frame yaw / psi angular speed*/ int32_t lat; /*< [degE7] Latitude*/ int32_t lon; /*< [degE7] Longitude*/ int32_t alt; /*< [mm] Altitude*/ int16_t vx; /*< [cm/s] Ground X Speed (Latitude)*/ int16_t vy; /*< [cm/s] Ground Y Speed (Longitude)*/ int16_t vz; /*< [cm/s] Ground Z Speed (Altitude)*/ int16_t xacc; /*< [mG] X acceleration*/ int16_t yacc; /*< [mG] Y acceleration*/ int16_t zacc; /*< [mG] Z acceleration*/ }) mavlink_hil_state_t;What am i doing wrong? How can i change the return type of the data function?
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@MaxBec said in Change the return type of model->data() function from QVariant to custom type:
How can i change the return type of the data function?
QAbstractItemModel::data() returns a QVariant - you can't change this. What you can do is to put your custom struct into a QVariant. See QVariant::fromValue() and the documentation to Q_DECLARE_METATYPE
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I've put this declaration now in my main.cpp:
Q_DECLARE_METATYPE(mavlink_hil_state_t); int main(int argc, char *argv[]) {New error:
/Applications/Qt/5.14.0/clang_64/lib/QtCore.framework/Headers/qmetatype.h:1810: Fehler: static_assert failed due to requirement 'bool(QMetaTypeId2<__mavlink_hil_state_t>::Defined)' "Type is not registered, please use the Q_DECLARE_METATYPE macro to make it known to Qt's meta-object system" Q_STATIC_ASSERT_X(QMetaTypeId2<T>::Defined, "Type is not registered, please use the Q_DECLARE_METATYPE macro to make it known to Qt's meta-object system"); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -
From the doc: "Ideally, this macro should be placed below the declaration of the class or struct. If that is not possible, it can be put in a private header file which has to be included every time that type is used in a QVariant."
