Fix issue #92, adding onDestroy Microflow for widgets, removing Chart Entity fixes memory leak

Author: Jelte Lagendijk

src/ChartJS/widgets/BarChart/BarChart.xml

@@ -248,6 +248,14 @@
             <description>Microflow to invoke when chart canvas is clicked. This Microflow will pass the Datapoint object 'Data point entity'</description>
             <returnType type="Void"></returnType>
         </property>
+        <property key="onDestroyMf" type="microflow" required="false" entityProperty="sourceentity">
+            <caption>On Destroy Microflow</caption>
+            <category>Behavior</category>
+            <description>Microflow to be called when the widget is destroyed. This can be used to destroy the Chart Entity from 'Data Source'.
+
+Note: This is experimental. In case of non-persistent objects this should not be necessary, and in MX 7 this is useless. Only use this if you experience memory leaks in Mendix 5</description>
+            <returnType type="Void"></returnType>
+        </property>
         <!-- Settings -->
         <property key="responsive" type="boolean" required="true" defaultValue="true">
             <caption>Responsive</caption>

src/ChartJS/widgets/Core.js

@@ -76,8 +76,6 @@ define([
 
         _tooltipNode: null,
 
-        _chartEntityObject: null,
-
         startup: function () {
             logger.debug(this.id + ".startup");
 
@@ -188,8 +186,6 @@ define([
                         return;
                     }
 
-                    this._chartEntityObject = obj;
-
                     // Retrieve datasets
                     mx.data.get({
                         guids: guids,
@@ -233,7 +229,6 @@ define([
                         dataset = null;
 
                     this._data.object = obj;
-                    this._chartEntityObject = obj;
 
                     // Retrieve datasets
                     mx.data.get({
@@ -293,13 +288,16 @@ define([
                     }
                 }
 
-                if (this._chartEntityObject !== null) {
-                    logger.debug(this.id + ".uninitialize release obj " + this._chartEntityObject.getGuid());
-                    mx.data.release(this._chartEntityObject);
-                }
-
                 if (this._data.object && this._data.object.getGuid) {
-                    mx.data.release(this._data.object);
+                    if (this.onDestroyMf) {
+                        this._executeMicroflow(this.onDestroyMf, lang.hitch(this, function () {
+                            logger.debug(this.id + ".uninitialize release obj " + this._data.object.getGuid());
+                            mx.data.release(this._data.object);
+                        }), this._data.object);
+                    } else {
+                        logger.debug(this.id + ".uninitialize release obj " + this._data.object.getGuid());
+                        mx.data.release(this._data.object);
+                    }
                 }
             }
         },
@@ -659,7 +657,7 @@ define([
         },
 
         _executeMicroflow: function (mf, callback, obj) {
-            logger.debug(this.id + "._executeMicroflow");
+            logger.debug(this.id + "._executeMicroflow " + mf);
             var _params = {
                 applyto: "selection",
                 actionname: mf,

src/ChartJS/widgets/DoughnutChart/DoughnutChart.xml

@@ -211,6 +211,14 @@
                 <description>Microflow to invoke when chart canvas is clicked. This Microflow will pass the Dataset object 'Data set entity'</description>
                 <returnType type="Void"></returnType>
             </property>
+            <property key="onDestroyMf" type="microflow" required="false" entityProperty="sourceentity">
+                <caption>On Destroy Microflow</caption>
+                <category>Behavior</category>
+                <description>Microflow to be called when the widget is destroyed. This can be used to destroy the Chart Entity from 'Data Source'.
+
+Note: This is experimental. In case of non-persistent objects this should not be necessary, and in MX 7 this is useless. Only use this if you experience memory leaks in Mendix 5</description>
+                <returnType type="Void"></returnType>
+            </property>
             <!-- Settings -->
             <property key="responsive" type="boolean" required="true" defaultValue="true">
                 <caption>Responsive</caption>

src/ChartJS/widgets/PieChart/PieChart.xml

@@ -213,6 +213,14 @@
             <description>Microflow to invoke when chart canvas is clicked. This Microflow will pass the Dataset object 'Data set entity'</description>
             <returnType type="Void"></returnType>
         </property>
+        <property key="onDestroyMf" type="microflow" required="false" entityProperty="sourceentity">
+            <caption>On Destroy Microflow</caption>
+            <category>Behavior</category>
+            <description>Microflow to be called when the widget is destroyed. This can be used to destroy the Chart Entity from 'Data Source'.
+
+Note: This is experimental. In case of non-persistent objects this should not be necessary, and in MX 7 this is useless. Only use this if you experience memory leaks in Mendix 5</description>
+            <returnType type="Void"></returnType>
+        </property>
         <!-- Settings -->
         <property key="responsive" type="boolean" required="true" defaultValue="true">
             <caption>Responsive</caption>

src/ChartJS/widgets/PolarChart/PolarChart.xml

@@ -203,6 +203,14 @@
                 <description>Microflow to invoke when chart canvas is clicked. This Microflow will pass the Dataset object 'Data set entity'</description>
                 <returnType type="Void"></returnType>
             </property>
+            <property key="onDestroyMf" type="microflow" required="false" entityProperty="sourceentity">
+                <caption>On Destroy Microflow</caption>
+                <category>Behavior</category>
+                <description>Microflow to be called when the widget is destroyed. This can be used to destroy the Chart Entity from 'Data Source'.
+
+Note: This is experimental. In case of non-persistent objects this should not be necessary, and in MX 7 this is useless. Only use this if you experience memory leaks in Mendix 5</description>
+                <returnType type="Void"></returnType>
+            </property>
             <!-- Settings -->
             <property key="responsive" type="boolean" required="true" defaultValue="true">
                 <caption>Responsive</caption>

src/ChartJS/widgets/RadarChart/RadarChart.xml

@@ -103,6 +103,14 @@
             <description>Microflow returning a 'Chart Entity' object.</description>
             <returnType type="Object" entityProperty="sourceentity"></returnType>
         </property>
+        <property key="onDestroyMf" type="microflow" required="false" entityProperty="sourceentity">
+            <caption>On Destroy Microflow</caption>
+            <category>Behavior</category>
+            <description>Microflow to be called when the widget is destroyed. This can be used to destroy the Chart Entity from 'Data Source'.
+
+Note: This is experimental. In case of non-persistent objects this should not be necessary, and in MX 7 this is useless. Only use this if you experience memory leaks in Mendix 5</description>
+            <returnType type="Void"></returnType>
+        </property>
         <!--<property key="sourceTrigger" type="attribute" entityProperty="sourceentity" allowNonPersistableEntities="true" required="false">
             <caption>Attribute to trigger</caption>
             <category>Data Set</category>