Changeset 7768

Timestamp:

Feb 7, 2020, 11:17:23 AM (22 months ago)

Author:

Nicklas Nordborg

Message:

References #2202: Include information from parent items in list pages

Implemented lazy-loading of data from the parent item colums. The column definition will generate a proxy html tag (ParentItemColumn.getProxyTag()) that a JavaScript (lazy-parent-items.js) can detect and initiate a lazy loading action via AJAX.

Location:

trunk

Files:

• src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemAnnotationColumn.java (modified) (1 diff)
• src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemColumn.java (modified) (7 diffs)
• src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemColumnActionFactory.java (modified) (3 diffs)
• src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemHelper.java (modified) (2 diffs)
• src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemPropertyColumn.java (modified) (1 diff)
• www/common/columns/ajax.jsp (added)
• www/include/scripts/lazy-parent-items.js (added)
• www/include/styles/table.css (modified) (1 diff)

trunk/src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemAnnotationColumn.java

@@ -22 +22 @@
   private final Filter<AnnotationSnapshot> atFilter;
   
-  ParentItemAnnotationColumn(String id, Filter<Annotatable> filter, ParentItemHelper helper, AnnotationType at)
+  ParentItemAnnotationColumn(int index, String id, Filter<Annotatable> filter, ParentItemHelper helper, AnnotationType at)
   {
-    super(id, filter, helper);
+    super(index, id, filter, helper);
     this.at = at;
     this.atFilter = new AnnotationTypeFilter(at);

trunk/src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemColumn.java

@@ -38 +38 @@
   */
   @SuppressWarnings({ "unchecked", "rawtypes" })
-  public static ParentItemColumn create(DbControl dc, String expr, ParentItemHelper helper)
+  public static ParentItemColumn create(DbControl dc, int index, String expr, ParentItemHelper helper)
   {
     ParentItemColumn col = null;
@@ -50 +50 @@
       {
         AnnotationType at = AnnotationType.getById(dc, Values.getInt(tmp[3].substring(1)));
-        col = new ParentItemAnnotationColumn(expr, parentFilter, helper, at);
+        col = new ParentItemAnnotationColumn(index, expr, parentFilter, helper, at);
         col.setTitle(at.getName() + " [A]");
         col.setTooltip(subtype.getName() + " › "+at.getName());
         col.setValueType(at.getValueType());
         col.setExportFormatter(FormatterFactory.getTypeFormatter(dc.getSessionControl(), at.getValueType()));
-        col.setFormatter(new CollectionFormatter(col.getExportFormatter()));
+        if (!helper.lazy) col.setFormatter(new CollectionFormatter(col.getExportFormatter()));
       }
       else
@@ -65 +65 @@
           Metadata m = Metadata.getInstance(parentType.getItemClass());
           property = m.getPropertyPath(path, false);
-          col = new ParentItemPropertyColumn(expr, parentFilter, helper, property);
+          col = new ParentItemPropertyColumn(index, expr, parentFilter, helper, property);
           col.setTitle(subtype.getName()+"."+path);
           col.setTooltip(subtype.getName() + " › "+path);
@@ -71 +71 @@
         else
         {
-          col = new ParentItemPropertyColumn(expr, parentFilter, helper, null);
+          col = new ParentItemPropertyColumn(index, expr, parentFilter, helper, null);
           col.setTitle(subtype.getName());
           col.setTooltip(subtype.getName());
@@ -78 +78 @@
         {
           col.setExportFormatter(new NameableFormatter());
-          col.setFormatter(new CollectionFormatter(new LinkedItemFormatter()));
+          if (!helper.lazy) col.setFormatter(new CollectionFormatter(new LinkedItemFormatter()));
         }
         else
         {
           col.setExportFormatter(new ToStringFormatter<>());
-          col.setFormatter(new CollectionFormatter(col.getExportFormatter()));
+          if (!helper.lazy) col.setFormatter(new CollectionFormatter(col.getExportFormatter()));
         }
       }
@@ -93 +93 @@
   }
 
+  private final int index;
   private final Filter<Annotatable> filter;
   private final ParentItemHelper helper;
   
-  ParentItemColumn(String id, Filter<Annotatable> filter, ParentItemHelper helper)
+  ParentItemColumn(int index, String id, Filter<Annotatable> filter, ParentItemHelper helper)
   {
+    this.index = index;
     this.filter = filter;
     this.helper = helper;
@@ -115 +117 @@
   public final Object getValue(DbControl dc, Annotatable item) 
   {
+    if (helper.lazy) return getProxyTag(item);
     item = helper.recycle(dc, item);
     return getValue(helper, item);
   }
 
+  /**
+    Generate a proxy tag that is returned instead of actual data. A
+    JavaScript in 'lazy-parent-items.js' will scan the table and
+    inject the actual data in batches.
+  */
+  private String getProxyTag(Annotatable item)
+  {
+    StringBuilder sb = new StringBuilder();
+    sb.append("<div");
+    sb.append(" class=\"lazy-parent not-loaded\"");
+    sb.append(" id=\"lazy-parent-").append(index).append("-").append(item.getId()).append("\"");
+    sb.append(" data-item-id=\"").append(item.getId()).append("\"");
+    sb.append(" data-index=\"").append(index).append("\"");
+    sb.append("></div>");
+    return sb.toString();
+  }
+  
+  /**
+    We finalize this implementation to make sure that the helper 
+    implementation always get a chance to re-cycle transactions.
+    Subclasses should implement {@link #getValue(ParentItemHelper, Annotatable)}
+    to return the requested value from the item and use the
+    DbControl from {@link ParentItemHelper#dc}.
+  */
+  @Override
+  public final Object getExportValue(DbControl dc, Annotatable item) 
+  {
+    item = helper.recycle(dc, item);
+    return getValue(helper, item);
+  }
+
+  
   /**
     Alternate implementation for loading data.

trunk/src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemColumnActionFactory.java

@@ -55 +55 @@
     if (allColumns == null || !allColumns.contains("/")) return false;
 
+    jspContext.addScript(jspContext.getRoot() + "/include/scripts/lazy-parent-items.js");
     return super.prepareContext(context);
   }
@@ -75 +76 @@
     if (allColumns == null || !allColumns.contains("/")) return null;
     
+    
+    boolean lazy = !Boolean.FALSE.equals(jspContext.getAttribute("lazy-loading"));
     DbControl dc = jspContext.getDbControl();
-    ParentItemHelper helper = new ParentItemHelper(sc);
+    ParentItemHelper helper = new ParentItemHelper(sc, lazy);
     List<ListColumnAction<Annotatable, Object>> actions = new ArrayList<>(); 
     for (String col : allColumns.split(","))
@@ -82 +85 @@
       if (col.startsWith("/"))
       {
-        ListColumnAction<Annotatable, Object> action = ParentItemColumn.create(dc, col, helper);
+        ListColumnAction<Annotatable, Object> action = ParentItemColumn.create(dc, actions.size(), col, helper);
         if (action != null) actions.add(action);
       }

trunk/src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemHelper.java

@@ -24 +24 @@
   
   final SessionControl sc;
+  final boolean lazy;
   // Use the snapshot manager for efficient loading of annotations
   final SnapshotManager manager;
@@ -32 +33 @@
   DbControl dc;
   
-  ParentItemHelper(SessionControl sc) 
+  ParentItemHelper(SessionControl sc, boolean lazy) 
   {
     this.sc = sc;
+    this.lazy = lazy;
     this.manager = new SnapshotManager();
     this.cache = AnnotationUtil.createCache();

trunk/src/clients/web/net/sf/basedb/clients/web/extensions/list/ParentItemPropertyColumn.java

@@ -22 +22 @@
   private final PropertyPath<? super Annotatable, ?> property;
   
-  ParentItemPropertyColumn(String id, Filter<Annotatable> filter, ParentItemHelper helper, PropertyPath<? super Annotatable, ?> property)
+  ParentItemPropertyColumn(int index, String id, Filter<Annotatable> filter, ParentItemHelper helper, PropertyPath<? super Annotatable, ?> property)
   {
-    super(id, filter, helper);
+    super(index, id, filter, helper);
     this.property = property;
   }

trunk/www/include/styles/table.css

@@ -377 +377 @@
 }
 
-
+.lazy-parent.not-loaded
+{
+  outline: 1px dotted #A0A0A0;
+    margin: 0 1em;
+    height: 3px;
+}
+
+