[#635] add onfocus handler and greyed-out nil-value support to name-one

hobo/rails_generators/hobo_rapid/templates/hobo-rapid.js

@@ -867,9 +867,10 @@ NameManyInput = Object.extend(SelectManyInput, {
     }
 })
 
-                              
+
 AutocompleteBehavior = Behavior.create({
     initialize : function() {
+        this.minChars  = parseInt(Hobo.getClassData(this.element, "min-chars")); 
         var match     = this.element.className.match(/complete-on::([\S]+)/)
         var target    = match[1].split('::')
         var typedId   = target[0]
@@ -878,11 +879,22 @@ AutocompleteBehavior = Behavior.create({
         var spec = Hobo.parseModelSpec(typedId)
         var url = urlBase + "/" + Hobo.pluralise(spec.name) +  "/complete_" + completer
         var parameters = spec.id ? "id=" + spec.id : ""
-        new Ajax.Autocompleter(this.element, 
-                               this.element.next('.completions-popup'), 
-                               url, 
-                               {paramName:'query', method:'get', parameters: parameters});
+        this.autocompleter = new Ajax.Autocompleter(this.element, 
+            this.element.next('.completions-popup'), 
+            url, 
+            {paramName:'query', method:'get', parameters: parameters, minChars: this.minChars});
+    },
+
+    onfocus: function() {
+        if(this.element.hasClassName("nil-value")) {
+            this.element.value = '';
+            this.element.removeClassName("nil-value");
+        }
+        if(this.minChars==0) { 
+            this.autocompleter.activate();
+        }
     }
+
 })
 
 

hobo/rails_generators/hobo_rapid/templates/themes/clean/public/stylesheets/rapid-ui.css

@@ -97,4 +97,6 @@ select.dev-user-changer:hover { opacity: 1; }
 optgroup.disabled-option {
     color: #ccc;
     height: 1em;
-}
+}
+
+input.nil-value { color:grey; }

hobo/taglibs/rapid_forms.dryml

@@ -717,14 +717,26 @@ We're using an object as the complete-target rather than a class.   This allows
 
 There's another example of `<name-one>` use in the [recipes](http://cookbook.hobocentral.net/recipes/36-using-a-name-one-one-a).
 
+### Attributes:
+
+- `complete-target`, `completer`: see above
+- `min-chars`: The minimum number of characters that must be entered in the input field before an Ajax request is made.
+- `nil-value`: If there is no current value, this text will appear greyed out inside the control, and will disappear on focus.
+
+### Note:
+
+If you wish to set `min-chars` to 0, you will require this [patch to controls.js](http://github.com/bryanlarsen/scriptaculous/commit/3915b7b).   'controls.js' was added to your project via the rails generator, not via Hobo.
+
   -->
-<def tag="name-one" attrs="complete-target, completer"><%
+<def tag="name-one" attrs="complete-target, completer, min-chars, nil-value"><%
   complete_target ||= this_field_reflection.klass
   completer ||= (complete_target.is_a?(Class) ? complete_target : complete_target.class).name_attribute
+  min_chars ||= 1
+  value = name(:no_wrapper => true, :if_present => true)
   -%>
   <input type="text" name="#{param_name_for_this}" 
-         class="autocompleter #{type_and_field.dasherize} #{css_data :complete_on, typed_id(complete_target), completer}"
-         value="&name :no_wrapper => true, :if_present => true"
+         class="autocompleter #{type_and_field.dasherize} #{css_data :complete_on, typed_id(complete_target), completer} #{css_data :min_chars, min_chars} #{'nil-value' if value==''}"
+         value="#{value=='' ? nil_value : value}"
          merge-attrs/>
   <div class="completions-popup" style="display:none"></div>
 </def>