ComboGrid: add trigger to delete from ComboGrid

when we have a combogrid that may be empty, we now show a
little 'x' where the user can delete the content

this is not shown when the field is not allowed to be empty

we add a new css for this because triggers need a background image
with a very specific layout:

110x22px which is 5 icons in one image for the various states
(normal, hover, active, focused, focused hover)

the icon is taken from the theme-crisp
form/tag-field-item-close.png but rearranged to fit the size

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>

css/Makefile

@@ -1,6 +1,6 @@
 include ../defines.mk
 
-CSS=
+CSS=ext6-pmx.css
 
 all:
 

css/ext6-pmx.css

@@ -0,0 +1,3 @@
+.pmx-clear-trigger {
+    background-image: url(../images/pmx-clear-trigger.png);
+}

form/ComboGrid.js

@@ -38,6 +38,24 @@ Ext.define('Proxmox.form.ComboGrid', {
 
     editable: false,
 
+    triggers: {
+	clear: {
+	    cls: 'pmx-clear-trigger',
+	    weight: -1,
+	    hidden: true,
+	    handler: function() {
+		var me = this;
+		me.setValue('');
+	    }
+	}
+    },
+
+    setValue: function(value) {
+	var me = this;
+	me.triggers.clear.setVisible(!!value && me.allowBlank);
+	return me.callParent([value]);
+    },
+
     // override ExtJS method
     // if the field has multiSelect enabled, the store is not loaded, and
     // the displayfield == valuefield, it saves the rawvalue as an array

images/Makefile

@@ -1,6 +1,6 @@
 include ../defines.mk
 
-IMAGES=
+IMAGES=pmx-clear-trigger.png
 
 all: