Merge pull request #75 from woutervh-/pass-mode-to-event-listeners

Pass along mode to BrushEvent

README.md

@@ -169,3 +169,4 @@ When a [brush event listener](#brush_on) is invoked, it receives the current bru
 * `type` - the string “start”, “brush” or “end”; see [*brush*.on](#brush_on).
 * `selection` - the current [brush selection](#brushSelection).
 * `sourceEvent` - the underlying input event, such as mousemove or touchmove.
+* `mode` - the string “drag”, “space”, “handle” or “center”; the mode of the brush.

src/brush.js

@@ -301,20 +301,20 @@ function brush(dim) {
       if (++this.active === 1) this.state.emitter = this, this.starting = true;
       return this;
     },
-    start: function(event) {
-      if (this.starting) this.starting = false, this.emit("start", event);
+    start: function(event, mode) {
+      if (this.starting) this.starting = false, this.emit("start", event, mode);
       else this.emit("brush", event);
       return this;
     },
-    brush: function(event) {
-      this.emit("brush", event);
+    brush: function(event, mode) {
+      this.emit("brush", event, mode);
       return this;
     },
-    end: function(event) {
-      if (--this.active === 0) delete this.state.emitter, this.emit("end", event);
+    end: function(event, mode) {
+      if (--this.active === 0) delete this.state.emitter, this.emit("end", event, mode);
       return this;
     },
-    emit: function(type, event) {
+    emit: function(type, event, mode) {
       var d = select(this.that).datum();
       listeners.call(
         type,
@@ -323,6 +323,7 @@ function brush(dim) {
           sourceEvent: event,
           target: brush,
           selection: dim.output(this.state.selection),
+          mode,
           dispatch: listeners
         }),
         d
@@ -407,7 +408,7 @@ function brush(dim) {
     }
 
     redraw.call(that);
-    emit.start(event);
+    emit.start(event, mode.name);
 
     function moved(event) {
       for (const p of event.changedTouches || [event]) {
@@ -485,7 +486,7 @@ function brush(dim) {
           || selection[1][1] !== s1) {
         state.selection = [[w1, n1], [e1, s1]];
         redraw.call(that);
-        emit.brush(event);
+        emit.brush(event, mode.name);
       }
     }
 
@@ -503,7 +504,7 @@ function brush(dim) {
       overlay.attr("cursor", cursors.overlay);
       if (state.selection) selection = state.selection; // May be set by brush.move (on start)!
       if (empty(selection)) state.selection = null, redraw.call(that);
-      emit.end(event);
+      emit.end(event, mode.name);
     }
 
     function keydowned(event) {

src/event.js

@@ -2,13 +2,15 @@ export default function BrushEvent(type, {
   sourceEvent,
   target,
   selection,
+  mode,
   dispatch
 }) {
   Object.defineProperties(this, {
     type: {value: type, enumerable: true, configurable: true},
     sourceEvent: {value: sourceEvent, enumerable: true, configurable: true},
     target: {value: target, enumerable: true, configurable: true},
     selection: {value: selection, enumerable: true, configurable: true},
+    mode: {value: mode, enumerable: true, configurable: true},
     _: {value: dispatch}
   });
 }