Adding a slider to set the mission path angle

This is in addition to the existing text edit control.

src/FactSystem/FactControls/FactTextField.qml

@@ -16,6 +16,8 @@ QGCTextField {
     showUnits:  true
     showHelp:   true
 
+    signal updated()
+
     property Fact   fact: null
 
     property string _validateString
@@ -29,6 +31,7 @@ QGCTextField {
             var errorString = fact.validate(text, false /* convertOnly */)
             if (errorString === "") {
                 fact.value = text
+                _textField.updated()
             } else {
                 _validateString = text
                 qgcView.showDialog(validationErrorDialogComponent, qsTr("Invalid Value"), qgcView.showDialogDefaultWidth, StandardButton.Save | StandardButton.Cancel)
@@ -36,6 +39,7 @@ QGCTextField {
         } else {
             fact.value = text
             fact.valueChanged(fact.value)
+            _textField.updated()
         }
     }
 

src/PlanView/SurveyItemEditor.qml

@@ -90,6 +90,20 @@ Rectangle {
             FactTextField {
                 fact:                   missionItem.gridAngle
                 Layout.fillWidth:       true
+                onUpdated:              angleSlider.value = missionItem.gridAngle.value
+            }
+            QGCSlider {
+                id:                     angleSlider
+                minimumValue:           0
+                maximumValue:           359
+                stepSize:               1
+                tickmarksEnabled:       false
+                Layout.fillWidth:       true
+                Layout.columnSpan:      2
+                Layout.preferredHeight: ScreenTools.defaultFontPixelHeight * 1.5
+                onValueChanged:         missionItem.gridAngle.value = value
+                Component.onCompleted:  value = missionItem.gridAngle.value
+                updateValueWhileDragging: true
             }
 
             QGCLabel { text: qsTr("Turnaround dist") }