Only create new blocks in flyout at certain angle #179

core/flyout.js

@@ -140,6 +140,13 @@ Blockly.Flyout.prototype.height_ = 0;
  */
 Blockly.Flyout.prototype.verticalOffset_ = 0;
 
+/**
+ * Angle size at which blocks are created from a fixed flyout on touch.
+ * @type {number}
+ * @private
+*/
+Blockly.Flyout.prototype.directionRange_ = 140;
+
 /**
  * Creates the flyout's DOM.  Only needs to be called once.
  * @return {!Element} The flyout's SVG group.
@@ -301,7 +308,7 @@ Blockly.Flyout.prototype.setMetrics_ = function(xyRatio) {
 
 Blockly.Flyout.prototype.setVerticalOffset = function(verticalOffset) {
   this.verticalOffset_ = verticalOffset;
-}
+};
 
 /**
  * Move the toolbox to the edge of the workspace.
@@ -671,6 +678,8 @@ Blockly.Flyout.prototype.blockMouseDown_ = function(block) {
       // Left-click (or middle click)
       Blockly.Css.setCursor(Blockly.Css.Cursor.CLOSED);
       // Record the current mouse position.
+      flyout.startDragMouseY_ = e.clientY;
+      flyout.startDragMouseX_ = e.clientX;
       Blockly.Flyout.startDownEvent_ = e;
       Blockly.Flyout.startBlock_ = block;
       Blockly.Flyout.startFlyout_ = flyout;
@@ -751,12 +760,46 @@ Blockly.Flyout.prototype.onMouseMoveBlock_ = function(e) {
   }
   var dx = e.clientX - Blockly.Flyout.startDownEvent_.clientX;
   var dy = e.clientY - Blockly.Flyout.startDownEvent_.clientY;
-  // Still dragging within the sticky DRAG_RADIUS.
-  if (Math.sqrt(dx * dx + dy * dy) > Blockly.DRAG_RADIUS) {
+
+  // Direction goes from -180 to 180, with 0 toward the right and 90 on top.
+  var direction = Math.atan2(dy, dx) / Math.PI * 180;
+
+  // Do a direction check based on the flyout position
+  var directionCheck = false;
+  var range = Blockly.Flyout.startFlyout_.directionRange_;
+  if (Blockly.Flyout.startFlyout_.horizontalLayout_) {
+    if (Blockly.Flyout.startFlyout_.toolboxPosition_ == Blockly.TOOLBOX_AT_TOP) {
+      if (direction < 90 + range / 2 && direction > 90 - range / 2) {
+        directionCheck = true;
+      }
+    } else {
+      if (direction > -90 - range / 2 && direction < -90 + range / 2) {
+        directionCheck = true;
+      }
+    }
+  } else {
+    if (Blockly.Flyout.startFlyout_.toolboxPosition_ == Blockly.TOOLBOX_AT_LEFT) {
+      if (direction < range / 2 && direction > -range / 2) {
+        directionCheck = true;
+      }
+    } else {
+      if (direction < -180 + range / 2 || direction > 180 - range / 2) {
+        directionCheck = true;
+      }
+    }
+  }
+
+  // Don't create a block within the sticky drag radius,
+  // or if we failed the direction check.
+  if (Math.sqrt(dx * dx + dy * dy) > Blockly.DRAG_RADIUS && directionCheck) {
     // Create the block.
     Blockly.Flyout.startFlyout_.createBlockFunc_(Blockly.Flyout.startBlock_)(
         Blockly.Flyout.startDownEvent_);
+  } else {
+    // Do a scroll
+    Blockly.Flyout.startFlyout_.onMouseMove_(e);
   }
+  e.stopPropagation();
 };
 
 /**