Add JSONTreeModel

- Model for QTreeView
- Displays JSON objects in a tree view

source/RobotAPI/libraries/widgets/CMakeLists.txt

@@ -10,8 +10,14 @@ armarx_build_if(jsoncpp_FOUND "jsoncpp not available")
 set(LIB_NAME       RobotAPIWidgets)
 set(LIBS RobotAPICore)
 
-set(LIB_FILES DebugLayerControlWidget.cpp)
-set(LIB_HEADERS DebugLayerControlWidget.h)
+set(LIB_FILES
+    DebugLayerControlWidget.cpp
+    JSONTreeModel.cpp
+    )
+set(LIB_HEADERS
+    DebugLayerControlWidget.h
+    JSONTreeModel.h
+    )
 set(GUI_UIS DebugLayerControlWidget.ui)
 list(APPEND LIB_HEADERS ${GUI_UIS})
 

source/RobotAPI/libraries/widgets/JSONTreeModel.cpp

+#include "JSONTreeModel.h"
+
+namespace armarx
+{
+
+    void JSONTreeModel::setRoot(ValuePtr root)
+    {
+        this->root = root;
+        rows.clear();
+        rows[root] = 0;
+        parents.clear();
+        parents[root] = nullptr;
+        names.clear();
+        names[root] = "";
+    }
+
+    QModelIndex JSONTreeModel::index(int row, int column, const QModelIndex& parentIndex) const
+    {
+        ValuePtr parent = refFrom(parentIndex);
+        if (row >= (int)parent->size())
+        {
+            return QModelIndex();
+        }
+
+        ValuePtr child = nullptr;
+        if (parent->is_array())
+        {
+            child = &parent->at(row);
+            names[child] = "[" + std::to_string(row) + "]";
+        }
+        else if (parent->is_object())
+        {
+            auto it = parent->begin();
+            std::advance(it, row);
+            child = &it.value();
+            names[child] = it.key();
+        }
+
+        if (child)
+        {
+            parents[child] = parent;
+            rows[child] = row;
+
+            return createIndex(row, column, child);
+        }
+        else
+        {
+            return QModelIndex();
+        }
+
+    }
+
+    QModelIndex JSONTreeModel::parent(const QModelIndex& index) const
+    {
+        if (!index.isValid())
+        {
+            return QModelIndex();
+        }
+
+        ValuePtr child = refFrom(index);
+        ValuePtr parent = parents.at(child);
+        if (parent == nullptr)
+        {
+            return QModelIndex();
+        }
+        int row = rows.at(parent);
+
+        return createIndex(row, 0, parent);
+    }
+
+    int JSONTreeModel::rowCount(const QModelIndex& parentIndex) const
+    {
+        if (parentIndex.column() > 1)
+        {
+            return 0;
+        }
+
+        ValuePtr parent = refFrom(parentIndex);
+        if (parent->is_array() || parent->is_object())
+        {
+            return parent->size();
+        }
+        else
+        {
+            return 0;
+        }
+    }
+
+    int JSONTreeModel::columnCount(const QModelIndex& parent) const
+    {
+        return 2;
+    }
+
+    QVariant JSONTreeModel::data(const QModelIndex& index, int role) const
+    {
+        if (!index.isValid())
+        {
+            return QVariant();
+        }
+
+        if (role != Qt::DisplayRole)
+        {
+            return QVariant();
+        }
+
+        nlohmann::json* ref = refFrom(index);
+
+        if (index.column() == 0)
+        {
+            std::string const& name = names.at(ref);
+            return QVariant(name.c_str());
+        }
+
+        switch (ref->type())
+        {
+            case nlohmann::json::value_t::null:
+                return QVariant("null");
+            case nlohmann::json::value_t::object:
+                return QVariant("object");
+            case nlohmann::json::value_t::array:
+                return QVariant("array");
+            case nlohmann::json::value_t::string:
+                return QVariant(ref->get<std::string>().c_str());
+            case nlohmann::json::value_t::boolean:
+                return QVariant(ref->get<bool>());
+            case nlohmann::json::value_t::number_integer:
+                return QVariant(ref->get<int>());
+            case nlohmann::json::value_t::number_unsigned:
+                return QVariant(ref->get<unsigned int>());
+            case nlohmann::json::value_t::number_float:
+                return QVariant(ref->get<float>());
+
+            default:
+                return QVariant("n/a");
+        }
+    }
+
+    QVariant JSONTreeModel::headerData(int section, Qt::Orientation orientation, int role) const
+    {
+        if (role != Qt::DisplayRole)
+        {
+            return QVariant();
+        }
+
+        switch (section)
+        {
+            case 0:
+                return QVariant("Name");
+            case 1:
+                return QVariant("Value");
+            default:
+                return QVariant();
+        }
+    }
+
+    auto JSONTreeModel::refFrom(const QModelIndex& index) const -> ValuePtr
+    {
+        if (index.isValid())
+        {
+            return static_cast<ValuePtr>(index.internalPointer());
+        }
+        else
+        {
+            return root;
+        }
+    }
+
+}

source/RobotAPI/libraries/widgets/JSONTreeModel.h

+#pragma once
+
+#include <VirtualRobot/Util/json/json.hpp>
+#include <QAbstractItemModel>
+
+namespace armarx
+{
+
+    class JSONTreeModel : public QAbstractItemModel
+    {
+    public:
+        using ValuePtr = nlohmann::json*;
+
+        void setRoot(ValuePtr root);
+
+        // QAbstractItemModel interface
+        QModelIndex index(int row, int column, const QModelIndex& parent) const override;
+        QModelIndex parent(const QModelIndex& index) const override;
+        int rowCount(const QModelIndex& parent) const override;
+        int columnCount(const QModelIndex& parent) const override;
+        QVariant data(const QModelIndex& index, int role) const override;
+        QVariant headerData(int section, Qt::Orientation orientation, int role) const override;
+
+    private:
+        ValuePtr refFrom(QModelIndex const& index) const;
+
+    private:
+        mutable std::map<ValuePtr, int> rows;
+        mutable std::map<ValuePtr, ValuePtr> parents;
+        mutable std::map<ValuePtr, std::string> names;
+        ValuePtr root;
+    };
+
+}