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JavaFX TreeItem css style for different class field

I have TreeView filled by my own tree. In class Node I have field "type" which is one of NodeType. The problem is that I want have style for each type of NodeType, e.g. "type1" text color should be green, "type2" text color should be red. I'm new in javaFX. I found solution by james-d ( https://github.com/james-d/heterogeneous-tree-example ), but in this example css style depends on the class name, how can I make it for class field ?
View of TreeView

My understanding is you want a TreeCell that styles differently depending on the NodeType of the Node contained within the TreeItem of said TreeCell. All via CSS. Am I correct?
Assuming I am correct, there are 2 ways I can think of to accomplish this; both of which work best if there is a small number of known NodeTypes. The first involves the use of PseudoClass and the second uses the same strategy as the JavaFX Chart API.
First Option
Create a custom TreeCell that is tailored to using your Node type (i.e. specify the generic signature appropriately). In this custom TreeCell you declare as many PseudoClass static final fields as you need; one for each NodeType. Then you observe the NodeType of the whatever Node is currently displayed in the TreeCell and update the PseudoClass states accordingly.
Here is an example assuming NodeType is an enum that has two constants: HAPPY and SAD.
public class CustomTreeCell<T extends Node> extends TreeCell<T> {
private static final PseudoClass HAPPY = PseudoClass.getPseudoClass("happy");
private static final PseudoClass SAD = PseudoClass.getPseudoClass("sad");
// this listener will activate/deactivate the appropriate PseudoClass states
private final ChangeListener<NodeType> listener = (obs, oldVal, newVal) -> {
pseudoClassStateChanged(HAPPY, newVal == NodeType.HAPPY);
pseudoClassStateChanged(SAD, newVal == NodeType.SAD);
};
// use a weak listener to avoid a memory leak
private final WeakChangeListener<NodeType> weakListener = /* wrap listener */;
public CustomTreeCell() {
getStyleClass().add("custom-tree-cell");
itemProperty().addListener((obs, oldVal, newVal) -> {
if (oldVal != null) {
oldVal.nodeTypeProperty().removeListener(weakListener);
}
if (newVal != null) {
newVal.nodeTypeProperty().addListener(weakListener);
// need to "observe" the initial NodeType of the new Node item.
// You could call the listener manually to avoid code duplication
pseudoClassStateChanged(HAPPY, newVal.getNodeType() == NodeType.HAPPY);
pseudoClassStateChanged(SAD, newVal.getNodeType() == NodeType.SAD);
} else {
// no item in this cell so deactivate all PseudoClass's
pseudoClassStateChanged(HAPPY, false);
pseudoClassStateChanged(SAD, false);
}
});
}
}
Then in your CSS file you can use:
.custom-tree-cell:happy {
/* style when happy */
}
.custom-tree-cell:sad {
/* style when sad */
}
Second Option
Do what the JavaFX Chart API does when dealing with multiple series of data. What it does is dynamically update the style class of the nodes depending on the series' index in a list (e.g. .line-chart-series-data-<index> <-- probably not exactly this).
/*
* Create a custom TreeCell like in the first option but
* without any of the PseudoClass code. This listener should
* be added/removed from the Node item just like weakListener
* is above.
*/
ChangeListener<NodeType> listener = (obs, oldVal, newVal) -> {
// You have to make sure you keep "cell", "indexed-cell", and "tree-cell"
// in order to keep the basic modena styling.
if (newVal == NodeType.HAPPY) {
getStyleClass().setAll("cell", "indexed-cell", "tree-cell", "custom-tree-cell-happy");
} else if (newVal == NodeType.HAPPY) {
getStyleClass().setAll("cell", "indexed-cell", "tree-cell", "custom-tree-cell-sad");
} else {
getStyleClass().setAll("cell", "indexed-cell", "tree-cell"); // revert to regular TreeCell style
}
};
Then in CSS:
.custom-tree-cell-happy {
/* styles */
}
.custom-tree-cell-sad {
/* styles */
}
Both of these options are really only viable when there is a small set of known types. It might become unmaintainable when you have something like 10+ NodeTypes. It becomes pretty much impossible if the number of NodeTypes is dynamic at runtime.
It might be easier to have NodeType, or some intermediate class/data structure, know what color the text should be and set the color programmatically based on the NodeType.
Note: I quickly typed up the code in my answer and did not test it. There may be compiler errors, runtime exceptions, or logic errors in my code.
Edit
Something else came to mind. My code above assumes that NodeType is held in a property and can be changed during runtime. If NodeType is static (unchanging) for each Node then the code can be vastly simplified. Instead of using any listeners you can simple override the following method declared in javafx.scene.control.Cell:
protected void updateItem(Node item, boolean empty)
This method is called every time a new item is set on the cell. Read the documentation, however, as overriding this method requires certain things from the developer (such as calling the super implementation).

Hiding Multiple Elements in JTable via ButtonClick

I am currently working on a tool which edits data dynamically in a JTable. I want to hide the targeted row whenever a button is clicked. Right now I am using RowFilter. Whenever the button isClicked, a new filter is created:
RowFilter<MyTableModel, Object> rowFilter = null;
try {
rowFilter = RowFilter.notFilter(RowFilter.regexFilter(((String)dataTable.getValueAt(dataTable.getSelectedRow(), 0)),0));
} catch (java.util.regex.PatternSyntaxException e) {
return;
}
sorter.setRowFilter(rowFilter);
This only works for one element each time the button is clicked. I want to stay them hidden, so you can continously hide elemtens in the table. It is important to mention that I do not want to delete the rows, just hide them.
I hope someone has an easy answer for this, looking for quite a while now.

This method sorter.setRowFilter(rowFilter); is replacing the filter every time you "add" a new filter. So, it's "forgetting" the old rules. What you have to do is edit the existing filter to include the new rules for filtering.
Check out the documentation for more details.
In any case, I extracted a part of the documentation which you should try to implement.
From RowFilter Javadoc:
Subclasses must override the include method to indicate whether the
entry should be shown in the view. The Entry argument can be used to
obtain the values in each of the columns in that entry. The following
example shows an include method that allows only entries containing
one or more values starting with the string "a":
RowFilter<Object,Object> startsWithAFilter = new RowFilter<Object,Object>() {
public boolean include(Entry<? extends Object, ? extends Object> entry) {
for (int i = entry.getValueCount() - 1; i >= 0; i--) {
if (entry.getStringValue(i).startsWith("a")) {
// The value starts with "a", include it
return true;
}
}
// None of the columns start with "a"; return false so that this
// entry is not shown
return false;
}
};
This means that the include() method is going to return true or false depending if an item should be shown.
Therefore, you should only set the RowFilter once, and reimplment the include() method to match all the rules you currently have set upon your view.

java fx: Where is the constraint property saved when using GridPane.setRowIndex(...);

I was used to Swing and I'm now beginning with FX.
I came across a question which I couldn't find a answer reading the "Working With Layouts in JavaFX " Guide from Oracle and also doing some research on the internet.
In the FX API Guide for the GridPane Class there is an example about laying out the Objects:
here an excerpt from http://docs.oracle.com/javafx/2/api/javafx/scene/layout/GridPane.html :
GridPane gridpane = new GridPane();
// Set one constraint at a time...
Button button = new Button();
GridPane.setRowIndex(button, 1);
GridPane.setColumnIndex(button, 2);
...
// don't forget to add children to gridpane
gridpane.getChildren().addAll(button, label);
The row and column information is set via static methods of GridPane. This is also what the documentation says. I'd like to understand where this Layout Constraints are bound to the Node Object - in this case the button.
The Node API doc does not mention the layout constraints.
I found a lot information about setting Constraints eg for columns on a GridPane object, but I could not find about further information about this.
So how is the row/column information bound to the button or how can I retrieve this information from the button after it was applied ?
best regrads
guenter

Reading through the javaFX source code, GridPane's setRowIndex and setColumnIndex use the setConstraint method of it's superclass Pane, which looks like this:
static void setConstraint(Node node, Object key, Object value) {
if (value == null) {
node.getProperties().remove(key);
} else {
node.getProperties().put(key, value);
}
if (node.getParent() != null) {
node.getParent().requestLayout();
}
}
So the information gets stored directly in the node.

SmartGWT: is it possible to color a a certain row in a list grid?

all is it possible to color a certain Row in smartGWT listGrid ?
i want to color just 1 row , not all the listGrid

In SmartGWT, methods that end with Style (e.g.- getStyle, getBaseStyle, getCellStyle, etc.) need to return a CSS class defined elsewhere (.css file, inline css in application load jsp, etc.).
Same applies for setStyle methods.
Unless lot of CSS customizations are done warranting the need for such, using getCellCSSText would probably be the best option.
getCellCSSText returns CSS text per cell, and will be called during every redraw.
final ListGrid resultsGrid = new ListGrid() {
#Override
protected String getCellCSSText(ListGridRecord record, int rowNum, int colNum) {
String style = super.getCellCSSText(record, rowNum, colNum);
// conditions can check values in record using rowNum, colNum as well as record attributes
if (record.getAttribute("<grid-field-name>").equals(<value>)) {
if (this.getFieldName(colNum).equals("<certain-grid-field-name>") && record.getAttribute("<grid-field-name>").equals(<specific-value>)) {
style = "font-weight:bold"; // only that cell in that row becomes bold
} else {
style = "color:red"; // all other cells in that row become red
}
} else if (record.getAttribute("<other-grid-field-name>").equals(<value>)) {
style = "color:green"; // entire row changed to green if one column in this row contain a specific value
}
return style;
}
};
Its not required to extend ListGridRecord as indicated in showcase sample linked above, unless there are other reasons to do so.

Never used SmartGWT, but looking at the JavaDoc, I'd say:
listGrid.getRecord(recordNum)
setCustomStyle(String customStyle)
setAttribute(String property, BaseClass value)
Also checkout this sample, that overrides the getBaseStyle() of the ListGrid.

SWT table: auto resize all columns

Qt solution is a single call to resizeColumnsToContent(), in .NET one can use TextRenderer.MeasureText(), JTable could use AUTO_RESIZE_ALL_COLUMNS.
In SWT, is there a way to programmaticaly resize columns after populating them?
Calling computeSize(SWT.DEFAULT, SWT.DEFAULT) returns the same value thus disregarding character left overs in columns.
TableColumn has setWidth(), but how do I obtain the size hint for the current content taking into account font face, etc?

Solved with:
private static void resizeColumn(TableColumn tableColumn_)
{
tableColumn_.pack();
}
private static void resizeTable(Table table_)
{
for (TableColumn tc : table.getColumns())
resizeColumn(tc);
}

In many cases, the table entries change at run-time to reflect changes in the data model. Adding entry to the data model requires to resize columns as well, but in my case calling .pack() after the modification of the model does not solved completly the problem. In particolar with decorations the last entry is never resized. This seams to be due to async table viewer update. This snipped solved my problem:
public class LabelDecoratorProvider extends DecoratingStyledCellLabelProvider {
public LabelDecoratorProvider(IStyledLabelProvider labelProvider,
ILabelDecorator decorator, IDecorationContext decorationContext) {
super(labelProvider, decorator, decorationContext);
}
#Override
public void update(ViewerCell cell) {
super.update(cell);
if (TableViewer.class.isInstance(getViewer())) {
TableViewer tableViewer = ((TableViewer)getViewer());
Table table = tableViewer.getTable();
for (int i = 0, n = table.getColumnCount(); i < n; i++)
table.getColumn(i).pack();
}
}
}