Revision: 10676
Author: gwt.mirror...@gmail.com
Date: Fri Sep 30 15:13:14 2011
Log: Gives CellTable an option to disable colgroup and/or don't attach
the message
panel. Disabling both leads to 50% faster layout time in IE (about 25%
each). The side effects are
1. Disabling colgroup will break fixed layout table with explicitly set
column width, and when styles are added to colgroup element. Therefore this
is turned off by default. Various checks are added to make sure
setColumnWidth and setTableLayoutFixed(true) are not called when colgroup
is disabled.
2. If the message panel is not attached to the table, loading indicator and
empty table widget are not displayed. Therefore this optimization is turned
off by default as well. A new method is added to get the message panel so
that callers can attach it to outside the table element.
Note, disabling colgroup also results in a very small gain in Firefox,
Chrome and Safari (around 5%). In addition, having the message panel
attached to the table itself actually results in better layout performance
in Chrome/Safari. It's recommended to leave inside the table for non-IE
browsers.
Review at http://gwt-code-reviews.appspot.com/1557804
Review by: jlaba...@google.com
http://code.google.com/p/google-web-toolkit/source/detail?r=10676
Modified:
/trunk/user/src/com/google/gwt/user/cellview/client/CellTable.java
=======================================
--- /trunk/user/src/com/google/gwt/user/cellview/client/CellTable.java Tue
Sep 20 12:53:34 2011
+++ /trunk/user/src/com/google/gwt/user/cellview/client/CellTable.java Fri
Sep 30 15:13:14 2011
@@ -499,6 +499,7 @@
private final TableCellElement tbodyLoadingCell;
private final TableSectionElement tfoot;
private final TableSectionElement thead;
+ private boolean colGroupEnabled = true;
/**
* Constructs a table with a default page size of 15.
@@ -576,15 +577,46 @@
*/
public CellTable(final int pageSize, Resources resources, ProvidesKey<T>
keyProvider,
Widget loadingIndicator) {
+ this(pageSize, resources, keyProvider, loadingIndicator, true, true);
+ }
+
+ /**
+ * Constructs a table with the specified page size, {@link Resources},
key
+ * provider, and loading indicator.
+ *
+ * @param pageSize the page size
+ * @param resources the resources to use for this widget
+ * @param keyProvider an instance of ProvidesKey<T>, or null if the
record
+ * object should act as its own key
+ * @param loadingIndicator the widget to use as a loading indicator, or
null
+ * to disable
+ * @param enableColGroup enable colgroup element. This is used when the
table is using fixed
+ * layout and when column style is added. Ignoring this element
will boost rendering
+ * performance. Note that when colgroup is disabled, {@link
#setColumnWidth},
+ * {@link setTableLayoutFixed} and {@link addColumnStyleName}
are no longe supported
+ * @param attachLoadingPanel attaching the table section that contains
the empty table widget and
+ * the loading indicator. Attaching this to the table
significantly improve the rendering
+ * performance in webkit based browsers but also introduces
significantly larger latency
+ * in IE. If the panel is not attached to the table, it won't
be displayed. But the user
+ * can call {@link #getTableLoadingSection} and attach it to
other elements outside the
+ * table element
+ */
+ public CellTable(final int pageSize, Resources resources, ProvidesKey<T>
keyProvider,
+ Widget loadingIndicator, boolean enableColGroup, boolean
attachLoadingPanel) {
super(Document.get().createTableElement(), pageSize, new
ResourcesAdapter(resources),
keyProvider);
this.style = resources.cellTableStyle();
this.style.ensureInjected();
+ this.colGroupEnabled = enableColGroup;
table = getElement().cast();
table.setCellSpacing(0);
- colgroup = Document.get().createColGroupElement();
- table.appendChild(colgroup);
+ if (enableColGroup) {
+ colgroup = Document.get().createColGroupElement();
+ table.appendChild(colgroup);
+ } else {
+ colgroup = null;
+ }
thead = table.createTHead();
// Some browsers create a tbody automatically, others do not.
if (table.getTBodies().getLength() > 0) {
@@ -593,7 +625,10 @@
tbody = Document.get().createTBodyElement();
table.appendChild(tbody);
}
- table.appendChild(tbodyLoading = Document.get().createTBodyElement());
+ tbodyLoading = Document.get().createTBodyElement();
+ if (attachLoadingPanel) {
+ table.appendChild(tbodyLoading);
+ }
tfoot = table.createTFoot();
setStyleName(resources.cellTableStyle().cellTableWidget());
@@ -623,6 +658,7 @@
@Override
public void addColumnStyleName(int index, String styleName) {
+ assertColumnGroupEnabled("Cannot add column style when colgroup is
disabled");
ensureTableColElement(index).addClassName(styleName);
}
@@ -644,8 +680,18 @@
return thead.getClientHeight();
}
+ /**
+ * Return the section that display loading indicator and the empty table
widget. If
+ * attachLoadingPanel is set to false in the constructor, this section
may not be attached
+ * to any element.
+ */
+ public TableSectionElement getTableLoadingSection() {
+ return tbodyLoading;
+ }
+
@Override
public void removeColumnStyleName(int index, String styleName) {
+ assertColumnGroupEnabled("Cannot remove column style when colgroup is
disabled");
if (index >= colgroup.getChildCount()) {
return;
}
@@ -664,6 +710,7 @@
*/
@Override
public void setColumnWidth(Column<T, ?> column, String width) {
+ assertColumnGroupEnabled("Cannot set column width when colgroup is
disabled");
// Overridden to add JavaDoc comments about fixed layout.
super.setColumnWidth(column, width);
}
@@ -729,6 +776,9 @@
* Specification</a>
*/
public void setTableLayoutFixed(boolean isFixed) {
+ if (isFixed && !colGroupEnabled) {
+ throw new IllegalStateException("Cannot set table to fixed layout
when colgroup is disabled");
+ }
if (isFixed) {
table.getStyle().setTableLayout(TableLayout.FIXED);
} else {
@@ -754,10 +804,15 @@
@Override
protected void doSetColumnWidth(int column, String width) {
- if (width == null) {
- ensureTableColElement(column).getStyle().clearWidth();
- } else {
- ensureTableColElement(column).getStyle().setProperty("width", width);
+ // This is invoked when column width is set (which will throw an
exception if colgroup is not
+ // enabled), and refreshColumnWidth/clearColumnWidth. The latter two
are no op if setColumnWidth
+ // is not invoked first.
+ if (colGroupEnabled) {
+ if (width == null) {
+ ensureTableColElement(column).getStyle().clearWidth();
+ } else {
+ ensureTableColElement(column).getStyle().setProperty("width",
width);
+ }
}
}
@@ -822,12 +877,24 @@
* column. Clearing the width would cause it to take up the remaining
width
* in a fixed layout table.
*/
- int colCount = colgroup.getChildCount();
- for (int i = getRealColumnCount(); i < colCount; i++) {
- doSetColumnWidth(i, "0px");
+ if (colGroupEnabled) {
+ int colCount = colgroup.getChildCount();
+ for (int i = getRealColumnCount(); i < colCount; i++) {
+ doSetColumnWidth(i, "0px");
+ }
}
}
+ /**
+ * Assert if colgroup is enabled, and throw an exception with the
supplied message if it's not
+ * enabled.
+ */
+ private void assertColumnGroupEnabled(String message) {
+ if (!colGroupEnabled) {
+ throw new IllegalStateException(message);
+ }
+ }
+
/**
* Get the {@link TableColElement} at the specified index, creating it if
* necessary.
--
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