feat(invisible notes): do not display invisible time signature.

Add AbstractNotationInstruction.PrintObject (xml attribute that says whether the object should be printed)

Fix InstrumentReader reading first attribute instead of "symbol" attribute it was looking for

src/MusicalScore/Graphical/MusicSystemBuilder.ts

@@ -488,7 +488,7 @@ export class MusicSystemBuilder {
             measure.addKeyAtBegin(currentKey, previousKey, currentClef);
             keyAdded = true;
         }
-        if (currentRhythm !== undefined) {
+        if (currentRhythm !== undefined && currentRhythm.PrintObject) {
             measure.addRhythmAtBegin(currentRhythm);
             rhythmAdded = true;
         }
@@ -615,7 +615,7 @@ export class MusicSystemBuilder {
         if (keyInstruction !== undefined) {
             measure.addKeyAtBegin(keyInstruction, this.activeKeys[visStaffIdx], this.activeClefs[visStaffIdx]);
         }
-        if (rhythmInstruction !== undefined) {
+        if (rhythmInstruction !== undefined && rhythmInstruction.PrintObject) {
             measure.addRhythmAtBegin(rhythmInstruction);
         }
         measure.PositionAndShape.BorderLeft = 0.0;

src/MusicalScore/ScoreIO/InstrumentReader.ts

@@ -720,18 +720,27 @@ export class InstrumentReader {
       this.abstractInstructions.push([1, keyInstruction]);
     }
     if (node.element("time") !== undefined) {
-      let symbolEnum: RhythmSymbolEnum = RhythmSymbolEnum.NONE;
       const timeNode: IXmlElement = node.element("time");
+      let symbolEnum: RhythmSymbolEnum = RhythmSymbolEnum.NONE;
+      let timePrintObject: boolean = true;
       if (timeNode !== undefined && timeNode.hasAttributes) {
-        const firstAttr: IXmlAttribute = timeNode.firstAttribute;
-        if (firstAttr.name === "symbol") {
-          if (firstAttr.value === "common") {
+        const symbolAttribute: IXmlAttribute = timeNode.attribute("symbol");
+        if (symbolAttribute) {
+          if (symbolAttribute.value === "common") {
             symbolEnum = RhythmSymbolEnum.COMMON;
-          } else if (firstAttr.value === "cut") {
+          } else if (symbolAttribute.value === "cut") {
             symbolEnum = RhythmSymbolEnum.CUT;
           }
         }
+
+        const printObjectAttribute: IXmlAttribute = timeNode.attribute("print-object");
+        if (printObjectAttribute) {
+          if (printObjectAttribute.value === "no") {
+            timePrintObject = false;
+          }
+        }
       }
+
       let num: number = 0;
       let denom: number = 0;
       const senzaMisura: boolean = (timeNode !== undefined && timeNode.element("senza-misura") !== undefined);
@@ -785,9 +794,11 @@ export class InstrumentReader {
           log.debug("InstrumentReader.addAbstractInstruction", errorMsg, ex);
         }
 
-        this.abstractInstructions.push([1, new RhythmInstruction(
+        const newRhythmInstruction: RhythmInstruction = new RhythmInstruction(
           new Fraction(num, denom, 0, false), symbolEnum
-        )]);
+        );
+        newRhythmInstruction.PrintObject = timePrintObject;
+        this.abstractInstructions.push([1, newRhythmInstruction]);
       } else {
         this.abstractInstructions.push([1, new RhythmInstruction(new Fraction(4, 4, 0, false), RhythmSymbolEnum.NONE)]);
       }

src/MusicalScore/VoiceData/Instructions/AbstractNotationInstruction.ts

@@ -7,6 +7,8 @@ export abstract class AbstractNotationInstruction {
     }
 
     protected parent: SourceStaffEntry;
+    /** States whether the object should be displayed. False if xmlNode.attribute("print-object").value = "no". */
+    private printObject: boolean = true;
 
     public get Parent(): SourceStaffEntry {
         return this.parent;
@@ -15,4 +17,11 @@ export abstract class AbstractNotationInstruction {
         this.parent = value;
     }
 
+    public get PrintObject(): boolean {
+        return this.printObject;
+    }
+
+    public set PrintObject(value: boolean) {
+        this.printObject = value;
+    }
 }