visually indicate empty categories by half-toning their buttons

HISTORY.md

@@ -16,7 +16,8 @@
     * block-instances can be dragged off from templates in the "export blocks", "unused blocks" and "hide blocks" dialogs
     * added "enter" key to key-pressed dropdown
     * added green flag symbol to message drop-down
-    * the green flag button's background color indicates whether the current scene is running or idle 
+    * the green flag button's background color indicates whether the current scene is running or idle
+    * empty categories are indicated by half-tone buttons
     * new preference setting per scene for pen color model and graphic effects, HSV or HSL, default is HSV
     * new preference setting per scene to "disable click-to-run" on blocks, for use in micro-world extensions
 * **Notable Changes:**
@@ -62,6 +63,9 @@
     * Chinese, thanks, Simon!
     * Brazilian Portuguese, thank you, Cassiano D'Andrea!
 
+### 2021-11-19
+* objects, byob, gui: visually indicate empty categories by half-toning their buttons
+
 ### 2021-11-18
 * gui: only pause generic hat blocks when loading a new project, not when switching to a new scene
 

snap.html

@@ -18,12 +18,12 @@
         <script src="src/widgets.js?version=2021-17-09"></script>
         <script src="src/blocks.js?version=2021-11-09"></script>
         <script src="src/threads.js?version=2021-11-15"></script>
-        <script src="src/objects.js?version=2021-11-15"></script>
+        <script src="src/objects.js?version=2021-11-19"></script>
         <script src="src/scenes.js?version=2021-11-12"></script>
-        <script src="src/gui.js?version=2021-11-18"></script>
+        <script src="src/gui.js?version=2021-11-19"></script>
         <script src="src/paint.js?version=2021-07-05"></script>
         <script src="src/lists.js?version=2021-07-19"></script>
-        <script src="src/byob.js?version=2021-11-09"></script>
+        <script src="src/byob.js?version=2021-11-19"></script>
         <script src="src/tables.js?version=2021-05-07"></script>
         <script src="src/sketch.js?version=2021-11-03"></script>
         <script src="src/video.js?version=2019-06-27"></script>

src/byob.js

@@ -110,7 +110,7 @@ WatcherMorph, XML_Serializer, SnapTranslator, SnapExtensions*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.byob = '2021-November-09';
+modules.byob = '2021-November-19';
 
 // Declarations
 
@@ -1368,6 +1368,7 @@ CustomCommandBlockMorph.prototype.deleteBlockDefinition = function () {
             ide = rcvr.parentThatIsA(IDE_Morph);
             if (ide) {
                 ide.flushPaletteCache();
+                ide.categories.refreshEmpty();
                 ide.refreshPalette();
                 ide.recordUnsavedChanges();
             }
@@ -2554,6 +2555,7 @@ BlockEditorMorph.prototype.updateDefinition = function () {
     this.refreshAllBlockInstances(oldSpec);
     ide = this.target.parentThatIsA(IDE_Morph);
     ide.flushPaletteCache();
+    ide.categories.refreshEmpty();
     ide.refreshPalette();
     ide.recordUnsavedChanges();
 };
@@ -4389,6 +4391,7 @@ BlockImportDialogMorph.prototype.importBlocks = function (name) {
             ide.stage.replaceDoubleDefinitionsFor(def);
         });
         ide.flushPaletteCache();
+        ide.categories.refreshEmpty();
         ide.refreshPalette();
         ide.showMessage(
             'Imported Blocks Module' + (name ? ': ' + name : '') + '.',
@@ -4480,6 +4483,7 @@ BlockRemovalDialogMorph.prototype.removeBlocks = function () {
             }
         });
         ide.flushPaletteCache();
+        ide.categories.refreshEmpty();
         ide.refreshPalette();
         ide.showMessage(
             this.blocks.length + ' ' + localize('unused block(s) removed'),

src/gui.js

@@ -86,7 +86,7 @@ BlockVisibilityDialogMorph, ThreadManager*/
 
 // Global stuff ////////////////////////////////////////////////////////
 
-modules.gui = '2021-November-18';
+modules.gui = '2021-November-19';
 
 // Declarations
 
@@ -1310,6 +1310,18 @@ IDE_Morph.prototype.createCategories = function () {
         });
     };
 
+    this.categories.refreshEmpty = function () {
+        var dict = myself.currentSprite.emptyCategories();
+        dict.variables = dict.variables || dict.lists || dict.other;
+        this.buttons.forEach(cat => {
+            if (dict[cat.category]) {
+                cat.enable();
+            } else {
+                cat.disable();
+            }
+        });
+    };
+
     function changePalette(category) {
         return () => {
             myself.currentCategory = category;
@@ -1353,6 +1365,7 @@ IDE_Morph.prototype.createCategories = function () {
             true // has preview
         );
 
+        button.category = category;
         button.corner = 8;
         button.padding = 0;
         button.labelShadowOffset = new Point(-1, -1);
@@ -1389,6 +1402,7 @@ IDE_Morph.prototype.createCategories = function () {
             true // has preview
         );
 
+        button.category = category;
         button.corner = 8;
         button.padding = 0;
         button.labelShadowOffset = new Point(-1, -1);
@@ -2818,7 +2832,7 @@ IDE_Morph.prototype.stopAllScripts = function () {
     this.stage.fireStopAllEvent();
 };
 
-IDE_Morph.prototype.selectSprite = function (sprite) {
+IDE_Morph.prototype.selectSprite = function (sprite, noEmptyRefresh) {
     // prevent switching to another sprite if a block editor or a block
     // visibility dialog box is open
     // so local blocks of different sprites don't mix
@@ -2837,6 +2851,9 @@ IDE_Morph.prototype.selectSprite = function (sprite) {
     }
     this.currentSprite = sprite;
     this.scene.currentSprite = sprite;
+    if (!noEmptyRefresh) {
+        this.categories.refreshEmpty();
+    }
     this.createPalette();
     this.createSpriteBar();
     this.createSpriteEditor();
@@ -4717,7 +4734,7 @@ IDE_Morph.prototype.aboutSnap = function () {
         module, btn1, btn2, btn3, btn4, licenseBtn, translatorsBtn,
         world = this.world();
 
-    aboutTxt = 'Snap! 7 - dev211118 -\nBuild Your Own Blocks\n\n'
+    aboutTxt = 'Snap! 7 - dev211119 -\nBuild Your Own Blocks\n\n'
         + 'Copyright \u24B8 2008-2021 Jens M\u00F6nig and '
         + 'Brian Harvey\n'
         + 'jens@moenig.org, bh@cs.berkeley.edu\n\n'
@@ -5010,6 +5027,7 @@ IDE_Morph.prototype.addPaletteCategory = function (name, color) {
     if (name === '') {return; }
     SpriteMorph.prototype.customCategories.set(name, color);
     this.createCategories();
+    this.categories.refreshEmpty();
     this.createPaletteHandle();
     this.categories.fixLayout();
     this.fixLayout();
@@ -5068,6 +5086,7 @@ IDE_Morph.prototype.deletePaletteCategory = function (name) {
     this.categories.fixLayout();
     this.flushPaletteCache();
     this.refreshPalette(true);
+    this.categories.refreshEmpty();
     this.fixLayout();
     this.recordUnsavedChanges();
 };
@@ -5653,6 +5672,7 @@ IDE_Morph.prototype.rawOpenBlocksString = function (str, name, silently) {
         new BlockImportDialogMorph(blocks, this.stage, name).popUp();
     }
     this.createCategories();
+    this.categories.refreshEmpty();
     this.createPaletteHandle();
     this.categories.fixLayout();
     this.fixLayout();
@@ -5843,7 +5863,7 @@ IDE_Morph.prototype.switchToScene = function (
         this.stage.pauseGenericHatBlocks();
     }
     this.createCorral(!refreshAlbum); // keep scenes
-    this.selectSprite(this.scene.currentSprite);
+    this.selectSprite(this.scene.currentSprite, true);
     this.corral.album.updateSelection();
     this.fixLayout();
     this.corral.album.contents.children.forEach(function (morph) {
@@ -5858,6 +5878,7 @@ IDE_Morph.prototype.switchToScene = function (
         this.categories.fixLayout();
         this.fixLayout();
         this.flushBlocksCache();
+        this.categories.refreshEmpty();
         this.currentSprite.palette(this.currentCategory);
         this.refreshPalette(true);
     }
@@ -6057,6 +6078,12 @@ IDE_Morph.prototype.flushPaletteCache = function (category) {
             }
         });
     }
+    this.stage.categoriesCache = null;
+    this.stage.children.forEach(m => {
+        if (m instanceof SpriteMorph) {
+            m.categoriesCache = null;
+        }
+    });
 };
 
 IDE_Morph.prototype.toggleZebraColoring = function () {
@@ -6297,6 +6324,7 @@ IDE_Morph.prototype.toggleStageSize = function (isSmall, forcedRatio) {
 
 IDE_Morph.prototype.toggleUnifiedPalette = function () {
     this.setUnifiedPalette(!this.scene.unifiedPalette);
+    this.recordUnsavedChanges();
 };
 
 IDE_Morph.prototype.setUnifiedPalette = function (bool) {
@@ -6314,9 +6342,9 @@ IDE_Morph.prototype.setUnifiedPalette = function (bool) {
     this.categories.fixLayout();
     this.fixLayout();
     this.flushBlocksCache();
+    this.categories.refreshEmpty();
     this.currentSprite.palette(this.currentCategory);
     this.refreshPalette(true);
-    this.recordUnsavedChanges();
     return true;
 };
 
@@ -6504,6 +6532,7 @@ IDE_Morph.prototype.reflectLanguage = function (lang, callback, noSave) {
     SpriteMorph.prototype.initBlocks();
     this.spriteBar.tabBar.tabTo('scripts');
     this.createCategories();
+    this.categories.refreshEmpty();
     this.createCorralBar();
     this.fixLayout();
     if (this.loadNewProject) {
@@ -6618,6 +6647,7 @@ IDE_Morph.prototype.setBlocksScale = function (num) {
     SpriteMorph.prototype.initBlocks();
     this.spriteBar.tabBar.tabTo('scripts');
     this.createCategories();
+    this.categories.refreshEmpty();
     this.createCorralBar();
     this.fixLayout();
     this.openProjectString(projectData);

src/objects.js

@@ -87,7 +87,7 @@ BlockVisibilityDialogMorph*/
 
 /*jshint esversion: 6*/
 
-modules.objects = '2021-November-15';
+modules.objects = '2021-November-19';
 
 var SpriteMorph;
 var StageMorph;
@@ -1870,6 +1870,7 @@ SpriteMorph.prototype.init = function (globals) {
 
     this.primitivesCache = {}; // not to be serialized (!)
     this.paletteCache = {}; // not to be serialized (!)
+    this.categoriesCache = null; // not to be serialized (!)
     this.rotationOffset = ZERO; // not to be serialized (!)
     this.idx = 0; // not to be serialized (!) - used for de-serialization
 
@@ -1935,6 +1936,7 @@ SpriteMorph.prototype.fullCopy = function (forClone) {
     c.freqPlayer = null;
     c.primitivesCache = {};
     c.paletteCache = {};
+    c.categoriesCache = {};
     c.imageData = {};
     c.cachedColorDimensions = c.color[this.penColorModel]();
     arr = [];
@@ -2957,6 +2959,7 @@ SpriteMorph.prototype.makeBlock = function () {
                     this.customBlocks.push(definition);
                 }
                 ide.flushPaletteCache();
+                ide.categories.refreshEmpty();
                 ide.refreshPalette();
                 ide.recordUnsavedChanges();
                 new BlockEditorMorph(definition, this).popUp();
@@ -3171,7 +3174,7 @@ SpriteMorph.prototype.freshPalette = function (category) {
 // SpriteMorph utilities for showing & hiding blocks in the palette
 
 SpriteMorph.prototype.allPaletteBlocks = function () {
-    // private - only to be used for showing & hiding blocks im the palette
+    // private - only to be used for showing & hiding blocks in the palette
     var blocks = SpriteMorph.prototype.allCategories().reduce(
         (blocks, category) => {
             let primitives = this.blockTemplates(category, true),
@@ -3259,6 +3262,21 @@ SpriteMorph.prototype.changeBlockVisibility = function (aBlock, hideIt, quick) {
     ide.refreshPalette();
 };
 
+SpriteMorph.prototype.emptyCategories = function () {
+    // return a dictionary that indicates for each category whether
+    // it has any shown blocks in it (true) or is empty (false)
+    var hasBlocks = (any) => any instanceof BlockMorph &&
+            !this.isHidingBlock(any);
+    if (this.categoriesCache === null) {
+        this.categoriesCache = {};
+        SpriteMorph.prototype.allCategories().forEach(category =>
+            this.categoriesCache[category] =
+                this.getPrimitiveTemplates(category).some(hasBlocks) ||
+                this.customBlockTemplatesForCategory(category).some(hasBlocks));
+    }
+    return this.categoriesCache;
+};
+
 // SpriteMorph blocks searching
 
 SpriteMorph.prototype.blocksMatching = function (
@@ -7772,6 +7790,7 @@ StageMorph.prototype.init = function (globals) {
     this.keysPressed = {}; // for handling keyboard events, do not persist
     this.primitivesCache = {}; // not to be serialized (!)
     this.paletteCache = {}; // not to be serialized (!)
+    this.categoriesCache = null; // not to be serialized (!)
     this.lastAnswer = ''; // last user input, do not persist
     this.activeSounds = []; // do not persist
 
@@ -9343,6 +9362,9 @@ StageMorph.prototype.changeCustomBlockVisibility
 StageMorph.prototype.changeVarBlockVisibility
     = SpriteMorph.prototype.changeVarBlockVisibility;
 
+StageMorph.prototype.emptyCategories =
+    SpriteMorph.prototype.emptyCategories;
+
 // StageMorph neighbor detection
 
 StageMorph.prototype.neighbors = SpriteMorph.prototype.neighbors;

sw.js

@@ -1,4 +1,4 @@
-var snapVersion = '7-dev211118'
+var snapVersion = '7-dev211119'
 
 var cacheName = 'snap-pwa',
     filesToCache = [