Avoid spurious errors while display is initializing

buba/static/display.js

@@ -1,5 +1,6 @@
 export default class {
     constructor(container, config = {}) {
+        this.ready = false;
         this.svgns = "http://www.w3.org/2000/svg";
         this.config = Object.assign({
             templateSvgUrl: "static/geascript-proportional.svg",
@@ -19,6 +20,7 @@ export default class {
                 let parser = new DOMParser();
                 this.segmentsDom = parser.parseFromString(new TextDecoder().decode(blob), 'image/svg+xml');
                 this.buildDisplay()
+                this.ready = true;
                 console.log("Done building display");
             })
             .catch(err => console.log(err));
@@ -47,8 +49,6 @@ export default class {
             rowSvg.id = `geavision__row_${r}_svg`;
             const width = this.config.stripWidth * this.config.cols
             rowSvg.setAttribute("viewBox", `0 0 ${parseInt(width)} ${parseInt(viewBox[3])}`);
-            // rowSvg.setAttribute("width", "320");
-            // rowSvg.setAttribute("height", "15");
 
             for (let c = 0; c < this.config.cols; c++) {
                 let g = document.createElementNS(this.svgns, "g");
@@ -67,6 +67,8 @@ export default class {
     }
 
     eraseCol(row, col) {
+        if (!this.ready)
+            return;
         for (let i = 1; i <= this.config.segments; i++) {
             const e = this.container.querySelector(`#geavision__row_${row}_${col}_${i}`)
             if (e) {
@@ -88,6 +90,8 @@ export default class {
     }
 
     applyCharacter(row, col, char) {
+        if (!this.ready)
+            return;
         let f = this.font[char];
         if (f === undefined)
             return 0;