Qt 5.7 | Qt Data Visualization | Qt Quick 2 Multiple Graphs Example

Qt 5.7.1 Reference Documentation

# Qt Quick 2 Multiple Graphs Example

The Qt Quick 2 multiple graphs example demonstrates using multiple graphs in single window.

The interesting thing about this example is demonstrating that multiple graphs can be used simultaneously, so most functionality is not explained in detail. For more detailed QML example documentation, see Qt Quick 2 Scatter Example.

## Multiple Graphs

Using multiple graphs in a single application doesn't require anything special, simply define and position the graphs as normal. In this example the graphs are shown in a 2 x 2 grid with `GridLayout`:

      GridLayout {
          id: gridLayout
          columns: 2
          Layout.fillHeight: true
          Layout.fillWidth: true
          anchors.top: mainView.top
          anchors.bottom: mainView.bottom
          anchors.left: mainView.left
          anchors.right: mainView.right

          Rectangle {
              Layout.fillHeight: true
              Layout.fillWidth: true
              border.color: surfaceGraph.theme.gridLineColor
              border.width: 2

              Surface3D {
                  id: surfaceGraph
                  anchors.fill: parent
                  anchors.margins: parent.border.width
                  theme: Theme3D {
                      type: Theme3D.ThemePrimaryColors
                      font.pointSize: 60
                  }
                  scene.activeCamera.cameraPreset: Camera3D.CameraPresetIsometricLeftHigh

                  Surface3DSeries {
                      itemLabelFormat: "Pop density at (@xLabel N, @zLabel E): @yLabel"
                      ItemModelSurfaceDataProxy {
                          itemModel: data.sharedData
                          // The surface data points are not neatly lined up in rows and columns,
                          // so we define explicit row and column roles.
                          rowRole: "row"
                          columnRole: "col"
                          xPosRole: "latitude"
                          zPosRole: "longitude"
                          yPosRole: "pop_density"
                      }
                  }
              }
          }

          // We'll use one grid cell for buttons
          Rectangle {
              Layout.fillHeight: true
              Layout.fillWidth: true

              GridLayout {
                  anchors.right: parent.right
                  anchors.left: parent.left
                  anchors.top: parent.top
                  anchors.bottom: parent.bottom
                  columns: 2

                  NewButton {
                      Layout.minimumWidth: parent.width / 2
                      Layout.fillHeight: true
                      Layout.fillWidth: true
                      text: "Clear Selections"
                      onClicked: clearSelections() // call a helper function to keep button itself simpler
                  }

                  NewButton {
                      Layout.minimumWidth: parent.width / 2
                      Layout.fillHeight: true
                      Layout.fillWidth: true
                      text: "Quit"
                      onClicked: Qt.quit(0);
                  }

                  NewButton {
                      Layout.fillHeight: true
                      Layout.fillWidth: true
                      text: "Reset Cameras"
                      onClicked: resetCameras() // call a helper function to keep button itself simpler
                  }

                  NewButton {
                      Layout.fillHeight: true
                      Layout.fillWidth: true
                      text: "Toggle Mesh Styles"
                      onClicked: toggleMeshStyle() // call a helper function to keep button itself simpler
                  }
              }
          }

          Rectangle {
              Layout.fillHeight: true
              Layout.fillWidth: true
              border.color: scatterGraph.theme.gridLineColor
              border.width: 2

              Scatter3D {
                  id: scatterGraph
                  anchors.fill: parent
                  anchors.margins: parent.border.width
                  theme: Theme3D {
                      type: Theme3D.ThemeDigia
                      font.pointSize: 60
                  }
                  scene.activeCamera.cameraPreset: Camera3D.CameraPresetIsometricLeftHigh

                  Scatter3DSeries {
                      itemLabelFormat: "Pop density at (@xLabel N, @zLabel E): @yLabel"
                      ItemModelScatterDataProxy {
                          itemModel: data.sharedData
                          // Mapping model roles to scatter series item coordinates.
                          xPosRole: "latitude"
                          zPosRole: "longitude"
                          yPosRole: "pop_density"
                      }
                  }
              }
          }

          Rectangle {
              Layout.fillHeight: true
              Layout.fillWidth: true
              border.color: barGraph.theme.gridLineColor
              border.width: 2

              Bars3D {
                  id: barGraph
                  anchors.fill: parent
                  anchors.margins: parent.border.width
                  theme: Theme3D {
                      type: Theme3D.ThemeQt
                      font.pointSize: 60
                  }
                  selectionMode: AbstractGraph3D.SelectionItemAndRow | AbstractGraph3D.SelectionSlice
                  scene.activeCamera.cameraPreset: Camera3D.CameraPresetIsometricLeftHigh

                  Bar3DSeries {
                      itemLabelFormat: "@seriesName: @valueLabel"
                      name: "Population density"

                      ItemModelBarDataProxy {
                          itemModel: data.sharedData
                          // Mapping model roles to bar series rows, columns, and values.
                          rowRole: "row"
                          columnRole: "col"
                          valueRole: "pop_density"
                      }
                  }
              }
          }
      }

Each graph has a parent `Rectangle` item to provide it with a border.

Note that one of the grid cells is used for buttons in an another `GridLayout`.

Files:

- qmlmultigraph/qml/qmlmultigraph/Data.qml
- qmlmultigraph/qml/qmlmultigraph/NewButton.qml
- qmlmultigraph/qml/qmlmultigraph/main.qml
- qmlmultigraph/main.cpp
- qmlmultigraph/qmlmultigraph.pro
- qmlmultigraph/qmlmultigraph.qrc