Adding engine selection UI control to DirectViewWidget.

IPython/frontend/html/notebook/widgets/directview.js

@@ -28,6 +28,19 b' DirectViewWidget.prototype.create_element = function () {'
     this.element.addClass('cell border-box-sizing code_cell vbox');
     this.element.attr('tabindex','2');
     this.element.css('padding-right',0);
+
+    var control = $('<div/>').addClass('dv_control').height('30px');
+    var control_label = $('<span/>').html('Select engine(s) to run code on interactively: ');
+    control_label.css('line-height','30px');
+    var select = $('<select/>').addClass('dv_select ui-widget ui-widget-content');
+    select.css('font-size','85%%').css('margin-bottom','5px');
+    var n = this.targets.length;
+    select.append($('<option/>').html('all').attr('value','all'));
+    for (var i=0; i<n; i++) {
+        select.append($('<option/>').html(this.targets[i]).attr('value',this.targets[i]))
+    }
+    control.append(control_label).append(select);
+
     var input = $('<div></div>').addClass('input hbox');
     var input_area = $('<div/>').addClass('input_area box-flex1');
     this.code_mirror = CodeMirror(input_area.get(0), {
@@ -38,7 +51,9 b' DirectViewWidget.prototype.create_element = function () {'
     });
     input.append(input_area);
     var output = $('<div></div>');
-    this.element.append(input).append(output);
+
+
+    this.element.append(control).append(input).append(output);
 	this.output_area = new IPython.OutputArea(output, false);
 
 };
@@ -100,7 +115,11 b' DirectViewWidget.prototype.execute = function () {'
         'output': $.proxy(this.output_area.handle_output, this.output_area),
         'clear_output': $.proxy(this.output_area.handle_clear_output, this.output_area),
     };
-    var code = '%(widget_var)s.execute("""'+this.get_text()+'""")';
+    var target = this.element.find('.dv_select option:selected').attr('value');
+    if (target === 'all') {
+        target = '"all"';
+    }
+    var code = '%(widget_var)s.execute("""'+this.get_text()+'""",targets='+target+')';
     console.log(code);
     console.log(this.get_text());
     var msg_id = this.kernel.execute(code, callbacks, {silent: false});

IPython/frontend/html/notebook/widgets/directview.py

@@ -50,18 +50,25 b' class DirectViewWidget(JavascriptWidget):'
         jscode = jscode % data
         return jscode
 
-    def execute(self,code):
-        ar = self.dv.execute(code,block=False,targets='all')
+    def execute(self, code, targets='all'):
+        if targets == 'all':
+            targets = self.targets
+        ar = self.dv.execute(code,block=False,targets=targets)
         ar.wait()
         metadata = ar.metadata
-        for md in metadata:
-            if md['stdout']:
-                publish_pretty(md['stdout'],{'engine_id':md['engine_id']})
-            if md['stderr']:
-                publish_pretty(md['stderr'],{'engine_id':md['engine_id']})
-            if md['pyerr']:
-                publish_pretty(md['pyerr'],{'engine_id':md['engine_id']})
-
+        if isinstance(metadata, (list,tuple)):
+            for md in metadata:
+                self.publish_md(md)
+        elif isinstance(metadata, dict):
+            self.publish_md(metadata)
+
+    def publish_md(self, md):
+        if md['stdout']:
+            publish_pretty(md['stdout'],{'engine_id':md['engine_id']})
+        if md['stderr']:
+            publish_pretty(md['stderr'],{'engine_id':md['engine_id']})
+        if md['pyerr']:
+            publish_pretty(md['pyerr'],{'engine_id':md['engine_id']})
 
 
 def interact(dv):