Measure: Add optional priority callback to measure types

src/App/Application.h

@@ -94,14 +94,21 @@ typedef struct MeasureElementInfo {
 
 using MeasureSelection = std::vector<std::tuple<std::string, std::string>>;
 using MeasureValidateMethod = std::function<bool(const MeasureSelection&)>;
+using MeasurePrioritizeMethod = std::function<bool(const MeasureSelection&)>;
 using MeasureInfoMethod = std::function<MeasureElementInfo(const char*, const char*)>;
 using MeasureTypeMethod = std::function<App::MeasureElementType (const char*, const char*)>;
 
 typedef struct MeasureType {
     std::string identifier;
     std::string label;
     std::string measureObject;
+
+    // Checks if the measurement works with a given selection
     MeasureValidateMethod validatorCb;
+
+    // Allows to prioritize this over other measurement types when the measurement type is picked implicitly from the selection.
+    // Gets called only when validatorCb returned true for the given selection
+    MeasurePrioritizeMethod prioritizeCb;
 } MeasureType;
 
 typedef struct MeasureHandler {

src/App/Measure.cpp

@@ -34,7 +34,7 @@ PROPERTY_SOURCE_ABSTRACT(App::MeasurementBase, App::DocumentObject)
 void App::Measure::initialize(){
     App::Application& app = App::GetApplication();
 
-    app.addMeasureType(new MeasureType{"LENGTH", "Length", "App::MeasureLength", App::MeasureLength::isValidSelection});
-    app.addMeasureType(new MeasureType{"ANGLE", "Angle", "App::MeasureAngle", App::MeasureAngle::isValidSelection});
+    app.addMeasureType(new MeasureType{"LENGTH", "Length", "App::MeasureLength", App::MeasureLength::isValidSelection, nullptr});
+    app.addMeasureType(new MeasureType{"ANGLE", "Angle", "App::MeasureAngle", App::MeasureAngle::isValidSelection, App::MeasureAngle::isPrioritizedSelection});
 
 }

src/App/MeasureAngle.cpp

@@ -89,6 +89,14 @@ bool MeasureAngle::isValidSelection(const App::MeasureSelection& selection){
     return true;
 }
 
+bool MeasureAngle::isPrioritizedSelection(const App::MeasureSelection& selection) {
+    if (selection.size() == 2) {
+        return true;
+    }
+
+    return false;
+}
+
 
 void MeasureAngle::parseSelection(const App::MeasureSelection& selection) {
 

src/App/MeasureAngle.h

@@ -68,6 +68,7 @@ class AppExport MeasureAngle : public App::MeasurementBaseExtendable<MeasureAngl
     // }
 
     static bool isValidSelection(const App::MeasureSelection& selection);
+    static bool isPrioritizedSelection(const App::MeasureSelection& selection);
     void parseSelection(const App::MeasureSelection& selection);
     Base::Quantity result() {return Angle.getQuantityValue();}
 

src/App/MeasureLength.cpp

@@ -53,7 +53,7 @@ MeasureLength::~MeasureLength() = default;
 
 bool MeasureLength::isValidSelection(const App::MeasureSelection& selection){
 
-    if (selection.size() != 1) {
+    if (selection.size() < 1) {
         return false;
     }
 

src/Gui/TaskMeasure.cpp

@@ -172,11 +172,17 @@ void TaskMeasure::update(){
             continue;
         }
 
-        isValid = true;
-        measureType = mType;
-        setModeSilent(mType);
+        // Check if the measurement type prioritizes the given selection
+        bool isPriority = (mType->prioritizeCb != nullptr && mType->prioritizeCb(selection));
 
-        break;
+        if (!isValid || isPriority) {
+            isValid = true;
+            measureType = mType;
+
+        }
+
+
+        // break;
     }
 
     if (!isValid) {
@@ -190,6 +196,8 @@ void TaskMeasure::update(){
         return;
     }
 
+    // Update tool mode display
+    setModeSilent(measureType);
 
     if (!_mMeasureObject || measureType->measureObject != _mMeasureObject->getTypeId().getName()) {
 

src/Mod/Part/App/Measure.cpp

@@ -261,7 +261,8 @@ void Measure::initialize() {
         "DISTANCEPOINTS",
         "Distance Points",
         "Part::MeasureDistancePoints",
-        Part::MeasureDistancePoints::isValidSelection
+        Part::MeasureDistancePoints::isValidSelection,
+        nullptr,
     });