JavaFX8: display an image as disclosure node for childless TreeViewItems - image

I have defined images for the two states of a disclosure node (collapse/expand) according to Change expand and collapse image TreeView JavaFX 2.2
But I would like to have a third image for folder nodes, which still haven't any children nodes. It should not possible to expand/collapse such nodes, but it should display an image too (i.e. a minus.png for expanded nodes, a plus.png for collapsed nodes and an empty rectangle for folder nodes without any children).
Is it possible?

Having no children means that tree item is leaf node with type of "folder". You can utilize graphic property of tree item to show "empty rectangle" image:
ImageView ivfolder = new ImageView( "path/to/empty_rectangle.png" );
// You may use bindings
treeitem.graphicProperty().bind( Bindings
.when( treeitem.leafProperty() )
.then( ivfolder )
.otherwise( ( ImageView ) null )
);
// or set explicitly for that tree item
TreeItem<Folder> item = new TreeItem<>( "<empty>", ivfolder );
Don't forget to create new imageviews for every treeitem added to treeView and which needs that image.

I have defined a css structure for the childless case:
.tree-cell:browser-folder-childless .tree-disclosure-node .arrow {
-fx-font-weight: bold;
-fx-shape: null;
-fx-background-color: null;
-fx-background-image: url("childless.png");
-fx-background-repeat: no-repeat;
}
.tree-cell:browser-folder-childless:expanded .tree-disclosure-node .arrow {
-fx-font-weight: bold;
-fx-shape: null;
-fx-background-color: null;
-fx-background-image: url("childless.png");
-fx-background-repeat: no-repeat;
}
Next I have extended the TreeItem class:
public class BrowserTreeItem extends TreeItem<MyData> {
public BrowserTreeItem(MyData data) {
super(data);
}
#Override
public boolean isLeaf() {
return (getValue().getTypes().contains(NodeType.FOLDER) && getValue().getChildren().size() == 0) ? false : super.isLeaf();
}
}
So the TreeItem returns always false for isLeaf() in the case of a childless folder. The isLeaf() method will be used by the com.sun.javafx.scene.control.skin.TreeCellSkin.class to decide, whether or not the disclosure node should be removed. Rebuilding the node could be tricky, so I prevent the remove of the node.
This results in a normal disclosure node, now I have to change the image of the node.
It would be nice to overwrite also the isExanded() method of the TreeItem class. Then I would need only one CSS structure (the method would return always false for childless folders). But isExpanded() is final. So I cannot prevent the not/expanded switch by the user and I have to define two CSS structures.
Next, I have built a TreeCellFactory, which generates my own BrowserTreeCell classes. It toggles a PseudoClass state, which we use in the CSS above to activate some new images for the disclosure node.
public class BrowserTreeCell extends TreeCell<MyData> {
private final PseudoClass childless = PseudoClass.getPseudoClass("browser-folder-childless");
#Override
protected void updateItem(MyData item, boolean empty) {
super.updateItem(item, empty);
if (!empty && item != null) {
setText(item.getName());
setGraphic(item.getThumbnail());
setTooltip(item.getTooltip());
} else {
setText("");
setGraphic(null);
setTooltip(null);
}
pseudoClassStateChanged(childless, !empty && item != null && item.getTypes().contains(NodeType.FOLDER) && item.getChildren().size() == 0);
}
}
As the result, I get a disclosure node with a "childless.png" in both cases (not/expanded).

Related

How to select multiple items in a TTreeView in code

I'm trying to select all the child node of a parent node when the parent is clicked, but when I for each node set the Selected = true i only end up with the last one being selected.
MultiSelect is true and I can do it with the mouse, so the setup should be ok.
For testing I use this code:
TTreeNode *node = Tv->Items->GetFirstNode();
node->Selected = true;
node = node->GetNext();
node->Selected = true;
node = node->GetNext();
node->Selected = true;
node = node->GetNext();
node->Selected = true;
Any tricks to make this work?
The TTreeNode::Selected property does not support multiple selections when toggling the node's selection state. Internally, it will call the Win32 TreeView_SelectItem() API, which selects a single node only.
For multi-select, use the TTreeView::Select() method instead:
The select method selects one or more tree nodes.
That being said, your example is attempting to select (potentially) every node in the TreeView, not just the child nodes of a parent node, as you claim.
Try this:
void AddNodeAndChildrenToList(TList *List, TTreeNode *Node)
{
List->Add(Node);
TTreeNode *child = Node->getFirstChild();
while (child)
{
AddNodeAndChildrenToList(List, child);
child = child->getNextSibling();
}
}
...
TList *nodes = new TList;
try
{
TTreeNode *parent = ...;
AddNodeAndChildrenToList(nodes, parent);
Tv->Select(nodes);
}
__finally
{
delete nodes;
}

CharmListView Infinite Scroll

I need basically an event that triggers at each 200 records loaded, so more data can be loaded until the end of data.
I tried to extend CharmListCell and using the method updateItem like this:
#Override
public void updateItem(Model item, boolean empty) {
super.updateItem(item, empty);
currentItem = item;
if (!empty && item != null) {
update();
setGraphic(slidingTile);
} else {
setGraphic(null);
}
System.out.println(getIndex());
}
But the System.out.println(getIndex()); method returns -1;
I would like to call my backend method when the scroll down gets the end of last fetched block and so on, until get the end of data like the "infinite scroll" technique.
Thanks!
The CharmListCell doesn't expose the index of the underlying listView, but even if it did, that wouldn't be of much help to find out if you are scrolling over the end of the current list or not.
I'd suggest a different approach, which is also valid for a regular ListView, with the advantage of having the CharmListView features (mainly headers and the refresh indicator).
This short sample, created with a single view project using the Gluon IDE plugin and Charm 5.0.0, shows how to create a CharmListView control, and fill it with 30 items at a time. I haven't provided a factory cell, nor the headers, and for the sake of simplicity I'm just adding consecutive integers.
With a lookup, and after the view is shown (so the listView is added to the scene) we find the vertical ScrollBar of the listView, and then we add a listener to track its position. When it gets closer to 1, we simulate the load of another batch of items, with a pause transition that represents a heavy task.
Note the use of the refresh indicator. When new data is added, we scroll back to the first of the new items, so we can keep scrolling again.
public class BasicView extends View {
private final ObservableList<Integer> data;
private CharmListView<Integer, Integer> listView;
private final int batchSize = 30;
private PauseTransition pause;
public BasicView() {
data = FXCollections.observableArrayList();
listView = new CharmListView<>(data);
setOnShown(e -> {
ScrollBar scrollBar = null;
for (Node bar : listView.lookupAll(".scroll-bar")) {
if (bar instanceof ScrollBar && ((ScrollBar) bar).getOrientation().equals(Orientation.VERTICAL)) {
scrollBar = (ScrollBar) bar;
break;
}
}
if (scrollBar != null) {
scrollBar.valueProperty().addListener((obs, ov, nv) -> {
if (nv.doubleValue() > 0.95) {
addBatch();
}
});
addBatch();
}
});
setCenter(new VBox(listView));
}
private void addBatch() {
listView.setRefreshIndicatorVisible(true);
if (pause == null) {
pause = new PauseTransition(Duration.seconds(1));
pause.setOnFinished(f -> {
int size = data.size();
List<Integer> list = new ArrayList<>();
for (int i = size; i < size + batchSize; i++) {
list.add(i);
}
data.addAll(list);
listView.scrollTo(list.get(0));
listView.setRefreshIndicatorVisible(false);
});
} else {
pause.stop();
}
pause.playFromStart();
}
}
Note also that you could benefit from the setOnPullToRefresh() method, at any time. For instance, if you add this:
listView.setOnPullToRefresh(e -> addBatch());
whenever you go to the top of the list and drag it down (on a mobile device), it will make another call to load a new batch of items. Obviously, this is the opposite behavior as the "infinite scrolling", but it is possible as well with the CharmListView control.

JavaFX weird (Key)EventBehavior

So I have been experimenting with it a litle bit with javaFX and I came across some rather weird behavior which might be linked to the TableView#edit() method.
I'll post a working example on the bottom of this post again, so you can see what exactually is happening on which cell (debuging included!).
I'll try to explain all the behavior myself, though its way easier to see it for yourself. Basically the events are messed up when using the TableView#edit() method.
1:
If you are using the contextMenu to add a new item, the keyEvents for the the keys 'escape' and 'Enter' (and propably the arrow keys, though I dont use them right now) are consumed before they fire the events on the Cells (e.g. textField and cell KeyEvents!) Though it is firing the keyEvent on the Parent node. (the AnchorPane in this case).
Now I know for a fact that these keys are captured and consumed by the contextMenu default behavior. Though it shouldn't be happening since the contextMenu is already hidden after the new item is added. further more the textField should recieve the events, especially when it is focused!
2:
When you use the button at the bottom of the TableView to add a new Item, The keyEvents are fired on the Parent node (the AnchorPane) and the Cell. Though the textField (even when focused) recieve no keyEvents at all. I cannot explain why the TextField wouldn't recieve any event even when typed in, so I assume that would definitely be a bug?
3:
When editing a cell through double click, it updates the editingCellProperty of the TableView correctly (which I check for several times). Though when start editing though the contextMenu Item (which only calls startEdit() for testpurpose) It doesnt update the editing state correctly! Funny enough it allows the keyEvents to continue as usual, unlike situation 1 & 2.
4:
When you edit an item, and then add an item (either way will cause this problem) it will update the editingCellProperty to the current cell, though when stop editing, it somehow revert back to the last Cell?!? Thats the part where funny things are happening, which I really cannot explain.
Note that the startEdit() & cancelEdit() methods are called in weird moments, and on the wrong Cells!
Right now I dont understand any of this logic. If this is intended behavior, some explanation of it would be greatly appreciated!
This is the example:
package testpacket;
import javafx.application.Application;
import javafx.beans.property.SimpleStringProperty;
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.event.ActionEvent;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.layout.AnchorPane;
import javafx.stage.Stage;
public class EditStateTest extends Application
{
private static ObservableList<SimpleStringProperty> exampleList = FXCollections.observableArrayList();
//Placeholder for the button
private static SimpleStringProperty PlaceHolder = new SimpleStringProperty();
public static void main(String[] args)
{
launch(args);
}
#Override
public void start(Stage primaryStage) throws Exception
{
// basic ui setup
AnchorPane parent = new AnchorPane();
Scene scene = new Scene(parent);
primaryStage.setScene(scene);
//fill backinglist with data
for(int i = 0 ; i < 20; i++)
exampleList.add(new SimpleStringProperty("Hello Test"));
exampleList.add(PlaceHolder);
//create a basic tableView
TableView<SimpleStringProperty> listView = new TableView<SimpleStringProperty>();
listView.setEditable(true);
TableColumn<SimpleStringProperty, String> column = new TableColumn<SimpleStringProperty, String>();
column.setCellFactory(E -> new TableCellTest<SimpleStringProperty, String>());
column.setCellValueFactory(E -> E.getValue());
column.setEditable(true);
// set listViews' backing list
listView.setItems(exampleList);
listView.getColumns().clear();
listView.getColumns().add(column);
parent.getChildren().add(listView);
parent.setOnKeyReleased(E -> System.out.println("Parent - KeyEvent"));
primaryStage.show();
}
// basic editable cell example
public static class TableCellTest<S, T> extends TableCell<S, T>
{
// The editing textField.
protected static Button addButton = new Button("Add");
protected TextField textField = new TextField();;
protected ContextMenu menu;
public TableCellTest()
{
this.setOnContextMenuRequested(E -> {
if(this.getTableView().editingCellProperty().get() == null)
this.menu.show(this, E.getScreenX(), E.getScreenY());
});
this.menu = new ContextMenu();
MenuItem createNew = new MenuItem("create New");
createNew.setOnAction(E -> {
System.out.println("Cell ContextMenu " + this.getIndex() + " - createNew: onAction");
this.onNewItem(this.getIndex() + 1);
});
MenuItem edit = new MenuItem("edit");
edit.setOnAction(E -> {
System.out.println("Cell ContextMenu " + this.getIndex() + " - edit: onAction");
this.startEdit();
});
this.menu.getItems().setAll(createNew, edit);
addButton.addEventHandler(ActionEvent.ACTION, E -> {
if(this.getIndex() == EditStateTest.exampleList.size() - 1)
{
System.out.println("Cell " + this.getIndex() + " - Button: onAction");
this.onNewItem(this.getIndex());
}
});
addButton.prefWidthProperty().bind(this.widthProperty());
this.setOnKeyReleased(E -> System.out.println("Cell " + this.getIndex() + " - KeyEvent"));
}
public void onNewItem(int index)
{
EditStateTest.exampleList.add(index, new SimpleStringProperty("New Item"));
this.getTableView().edit(index, this.getTableColumn());
textField.requestFocus();
}
#Override
public void startEdit()
{
if (!isEditable()
|| (this.getTableView() != null && !this.getTableView().isEditable())
|| (this.getTableColumn() != null && !this.getTableColumn().isEditable()))
return;
System.out.println("Cell " + this.getIndex() + " - StartEdit");
super.startEdit();
this.createTextField();
textField.setText((String)this.getItem());
this.setGraphic(textField);
textField.selectAll();
this.setText(null);
}
#Override
public void cancelEdit()
{
if (!this.isEditing())
return;
System.out.println("Cell " + this.getIndex() + " - CancelEdit");
super.cancelEdit();
this.setText((String)this.getItem());
this.setGraphic(null);
}
#Override
protected void updateItem(T item, boolean empty)
{
System.out.println("Cell " + this.getIndex() + " - UpdateItem");
super.updateItem(item, empty);
if(empty || item == null)
{
if(this.getIndex() == EditStateTest.exampleList.size() - 1)
{
this.setText("");
this.setGraphic(addButton);
}
else
{
this.setText(null);
this.setGraphic(null);
}
}
else
{
// These checks are needed to make sure this cell is the specific cell that is in editing mode.
// Technically this#isEditing() can be left out, as it is not accurate enough at this point.
if(this.getTableView().getEditingCell() != null
&& this.getTableView().getEditingCell().getRow() == this.getIndex())
{
//change to TextField
this.setText(null);
this.setGraphic(textField);
}
else
{
//change to actual value
this.setText((String)this.getItem());
this.setGraphic(null);
}
}
}
#SuppressWarnings("unchecked")
public void createTextField()
{
textField.setOnKeyReleased(E -> {
System.out.println("TextField " + this.getIndex() + " - KeyEvent");
System.out.println(this.getTableView().getEditingCell());
// if(this.getTableView().getEditingCell().getRow() == this.getIndex())
if(E.getCode() == KeyCode.ENTER)
{
this.setItem((T) textField.getText());
this.commitEdit(this.getItem());
}
else if(E.getCode() == KeyCode.ESCAPE)
this.cancelEdit();
});
}
}
}
I hope somebody could help me further with this. If you have suggestions/solutions or workarounds for this, please let me know!
Thanks for your time!
This is kind of the poster child for Josh Bloch's "Inheritance breaks Encapsulation" mantra. What I mean by that is that when you create a subclass of an existing class (TableCell in this case), you need to know a lot about the implementation of that class in order to make the subclass play nicely with the superclass. You make a lot of assumptions in your code about the interaction between the TableView and its cells that are not true, and that (along with some bugs and general weird implementations of event handling in some controls) is why your code is breaking.
I don't think I can address every single issue, but I can give some general pointers here and provide what I think is working code that achieves what you are trying to achieve.
First, cells are reused. This is a good thing, because it makes the table perform very efficiently when there is a large amount of data, but it makes it complicated. The basic idea is that cells are essentially only created for the visible items in the table. As the user scrolls around, or as the table content changes, cells that are no longer needed are reused for different items that become visible. This massively saves on memory consumption and CPU time (if used properly). In order to be able to improve the implementation, the JavaFX team deliberately don't specify how this works, and how and when cells are likely to be reused. So you have to be careful about making assumptions about the continuity of the item or index fields of a cell (and conversely, which cell is assigned to a given item or index), particularly if you change the structure of the table.
What you are basically guaranteed is:
Any time the cell is reused for a different item, the updateItem() method is invoked before the cell is rendered.
Any time the index of the cell changes (which may be because an item is inserted in the list, or may be because the cell is reused, or both), the updateIndex() method is invoked before the cell is rendered.
However, note that in the case where both change, there is no guarantee of the order in which these are invoked. So, if your cell rendering depends on both the item and the index (which is the case here: you check both the item and the index in your updateItem(...) method), you need to ensure the cell is updated when either of those properties change. The best way (imo) to achieve this is to create a private method to perform the update, and to delegate to it from both updateItem() and updateIndex(). This way, when the second of those is invoked, your update method is invoked with consistent state.
If you change the structure of the table, say by adding a new row, the cells will need to be rearranged, and some of them are likely to be reused for different items (and indexes). However, this rearrangement only happens when the table is laid out, which by default will not happen until the next frame rendering. (This makes sense from a performance perspective: imagine you make 1000 different changes to a table in a loop; you don't want the cells to be recalculated on every change, you just want them recalculated once the next time the table is rendered to the screen.) This means, if you add rows to the table, you cannot rely on the index or item of any cell being correct. This is why your call to table.edit(...) immediately after adding a new row is so unpredictable. The trick here is to force a layout of the table by calling TableView.layout() after adding the row.
Note that pressing "Enter" when a table cell is focused will cause that cell to go into editing mode. If you handle commits on the text field in a cell with a key released event handler, these handlers will interact in an unpredictable way. I think this is why you see the strange key handling effects you see (also note that text fields consume the key events they process internally). The workaround for that is to use an onAction handler on the text field (which is arguably more semantic anyway).
Don't make the button static (I have no idea why you would want to do this anyway). "Static" means that the button is a property of the class as a whole, not of the instances of that class. So in this case, all the cells share a reference to a single button. Since the cell reuse mechanism is unspecified, you don't know that only one cell will have the button set as its graphic. This can cause disaster. For example, if you scroll the cell with the button out of view and then back into view, there is no guarantee the same cell will be used to display that last item when it comes back into view. It is possible (I don't know the implementation) that the cell that previously displayed the last item is sitting unused (perhaps part of the virtual flow container, but clipped out of view) and is not updated. In that case, the button would then appear twice in the scene graph, which would either throw an exception or cause unpredictable behavior. There's basically no valid reason to ever make a scene graph node static, and here it's a particularly bad idea.
To code functionality like this, you should read extensively the documentation for the cell mechanism and for TableView, TableColumn, and TableCell. At some point you might find you need to dig into the source code to see how the provided cell implementations work.
Here's (I think, I'm not sure I've fully tested) a working version of what I think you were looking for. I made some slight changes to the structure (no need for StringPropertys as the data type, String works just fine as long as you have no identical duplicates), added an onEditCommit handler, etc.
import javafx.application.Application;
import javafx.beans.value.ObservableValueBase;
import javafx.scene.Scene;
import javafx.scene.control.Button;
import javafx.scene.control.ContextMenu;
import javafx.scene.control.MenuItem;
import javafx.scene.control.TableCell;
import javafx.scene.control.TableColumn;
import javafx.scene.control.TableView;
import javafx.scene.control.TextField;
import javafx.scene.input.KeyCode;
import javafx.scene.layout.BorderPane;
import javafx.stage.Stage;
public class TableViewWithAddAtEnd extends Application {
#Override
public void start(Stage primaryStage) {
TableView<String> table = new TableView<>();
table.setEditable(true);
TableColumn<String, String> column = new TableColumn<>("Data");
column.setPrefWidth(150);
table.getColumns().add(column);
// use trivial wrapper for string data:
column.setCellValueFactory(cellData -> new ObservableValueBase<String>() {
#Override
public String getValue() {
return cellData.getValue();
}
});
column.setCellFactory(col -> new EditingCellWithMenuEtc());
column.setOnEditCommit(e ->
table.getItems().set(e.getTablePosition().getRow(), e.getNewValue()));
for (int i = 1 ; i <= 20; i++) {
table.getItems().add("Item "+i);
}
// blank for "add" button:
table.getItems().add("");
BorderPane root = new BorderPane(table);
primaryStage.setScene(new Scene(root, 600, 600));
primaryStage.show();
}
public static class EditingCellWithMenuEtc extends TableCell<String, String> {
private TextField textField ;
private Button button ;
private ContextMenu contextMenu ;
// The update relies on knowing both the item and the index
// Since we don't know (or at least shouldn't rely on) the order
// in which the item and index are updated, we just delegate
// implementations of both updateItem and updateIndex to a general
// method. This way doUpdate() is always called last with consistent
// state, so we are guaranteed to be in a consistent state when the
// cell is rendered, even if we are temporarily in an inconsistent
// state between the calls to updateItem and updateIndex.
#Override
protected void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
doUpdate(item, getIndex(), empty);
}
#Override
public void updateIndex(int index) {
super.updateIndex(index);
doUpdate(getItem(), index, isEmpty());
}
// update the cell. This updates the text, graphic, context menu
// (empty cells and the special button cell don't have context menus)
// and editable state (empty cells and the special button cell can't
// be edited)
private void doUpdate(String item, int index, boolean empty) {
if (empty) {
setText(null);
setGraphic(null);
setContextMenu(null);
setEditable(false);
} else {
if (index == getTableView().getItems().size() - 1) {
setText(null);
setGraphic(getButton());
setContextMenu(null);
setEditable(false);
} else if (isEditing()) {
setText(null);
getTextField().setText(item);
setGraphic(getTextField());
getTextField().requestFocus();
setContextMenu(null);
setEditable(true);
} else {
setText(item);
setGraphic(null);
setContextMenu(getMenu());
setEditable(true);
}
}
}
#Override
public void startEdit() {
if (! isEditable()
|| ! getTableColumn().isEditable()
|| ! getTableView().isEditable()) {
return ;
}
super.startEdit();
getTextField().setText(getItem());
setText(null);
setGraphic(getTextField());
setContextMenu(null);
textField.selectAll();
textField.requestFocus();
}
#Override
public void cancelEdit() {
super.cancelEdit();
setText(getItem());
setGraphic(null);
setContextMenu(getMenu());
}
#Override
public void commitEdit(String newValue) {
// note this fires onEditCommit handler on column:
super.commitEdit(newValue);
setText(getItem());
setGraphic(null);
setContextMenu(getMenu());
}
private void addNewItem(int index) {
getTableView().getItems().add(index, "New Item");
// force recomputation of cells:
getTableView().layout();
// start edit:
getTableView().edit(index, getTableColumn());
}
private ContextMenu getMenu() {
if (contextMenu == null) {
createContextMenu();
}
return contextMenu ;
}
private void createContextMenu() {
MenuItem addNew = new MenuItem("Add new");
addNew.setOnAction(e -> addNewItem(getIndex() + 1));
MenuItem edit = new MenuItem("Edit");
// note we call TableView.edit(), not this.startEdit() to ensure
// table's editing state is kept consistent:
edit.setOnAction(e -> getTableView().edit(getIndex(), getTableColumn()));
contextMenu = new ContextMenu(addNew, edit);
}
private Button getButton() {
if (button == null) {
createButton();
}
return button ;
}
private void createButton() {
button = new Button("Add");
button.prefWidthProperty().bind(widthProperty());
button.setOnAction(e -> addNewItem(getTableView().getItems().size() - 1));
}
private TextField getTextField() {
if (textField == null) {
createTextField();
}
return textField ;
}
private void createTextField() {
textField = new TextField();
// use setOnAction for enter, to avoid conflict with enter on cell:
textField.setOnAction(e -> commitEdit(textField.getText()));
// use key released for escape: note text fields do note consume
// key releases they don't handle:
textField.setOnKeyReleased(e -> {
if (e.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
});
}
}
public static void main(String[] args) {
launch(args);
}
}
My big learn item of the day (freely summarized and slightly extended from James' answer):
view.edit(...) is safe to call only if all cells are in a stable state and the target cell is visible. Most of the time we can force the stable state by calling view.layout()
Below is yet another example to play with:
as already mentioned in one of my comments, it differs from James' in starting the edit in a listener to the items: might not always be the best place, has the advantage of a single location (at least as far as list mutations are involved) for the layout call. A drawback is that we need to be certain that the viewSkin's listener to the items is called before ours. To guarantee that, our own listener is re/registered whenever the skin changes.
as an exercise in re-use, I extended TextFieldTableCell to additionally handle the button/menu and update the cell's editability based on the row item.
there are also buttons outside the table to experiment with: addAndEdit and scrollAndEdit. The latter is to demonstrate that "instable cell state" can be reached by paths different from modifying the items.
Currently, I tend to subclass TableView and override its edit(...) to force the re-layout. Something like:
public static class TTableView<S> extends TableView<S> {
/**
* Overridden to force a layout before calling super.
*/
#Override
public void edit(int row, TableColumn<S, ?> column) {
layout();
super.edit(row, column);
}
}
Doing, relieves the burden on client code. What's left for them is to make sure the target cell is scrolled into the visible area, though.
The example:
public class TablePersonAddRowAndEdit extends Application {
private PersonStandIn standIn = new PersonStandIn();
private final ObservableList<Person> data =
// Person from Tutorial - with Properties exposed!
FXCollections.observableArrayList(
new Person("Jacob", "Smith", "jacob.smith#example.com"),
new Person("Isabella", "Johnson", "isabella.johnson#example.com"),
new Person("Ethan", "Williams", "ethan.williams#example.com"),
new Person("Emma", "Jones", "emma.jones#example.com"),
new Person("Michael", "Brown", "michael.brown#example.com")
, standIn
);
private Parent getContent() {
TableView<Person> table = new TableView<>();
table.setItems(data);
table.setEditable(true);
TableColumn<Person, String> firstName = new TableColumn<>("First Name");
firstName.setCellValueFactory(new PropertyValueFactory<>("firstName"));
firstName.setCellFactory(v -> new MyTextFieldCell<>());
ListChangeListener l = c -> {
while (c.next()) {
// true added only
if (c.wasAdded() && ! c.wasRemoved()) {
// force the re-layout before starting the edit
table.layout();
table.edit(c.getFrom(), firstName);
return;
}
};
};
// install the listener to the items after the skin has registered
// its own
ChangeListener skinListener = (src, ov, nv) -> {
table.getItems().removeListener(l);
table.getItems().addListener(l);
};
table.skinProperty().addListener(skinListener);
table.getColumns().addAll(firstName);
Button add = new Button("AddAndEdit");
add.setOnAction(e -> {
int standInIndex = table.getItems().indexOf(standIn);
int index = standInIndex < 0 ? table.getItems().size() : standInIndex;
index =1;
Person person = createNewItem("edit", index);
table.getItems().add(index, person);
});
Button edit = new Button("Edit");
edit.setOnAction(e -> {
int index = 1;//table.getItems().size() -2;
table.scrollTo(index);
table.requestFocus();
table.edit(index, firstName);
});
HBox buttons = new HBox(10, add, edit);
BorderPane content = new BorderPane(table);
content.setBottom(buttons);
return content;
}
/**
* A cell that can handle not-editable items. Has to update its
* editability based on the rowItem. Must be done in updateItem
* (tried a listener to the tableRow's item, wasn't good enough - doesn't
* get notified reliably)
*
*/
public static class MyTextFieldCell<S> extends TextFieldTableCell<S, String> {
private Button button;
public MyTextFieldCell() {
super(new DefaultStringConverter());
ContextMenu menu = new ContextMenu();
menu.getItems().add(createMenuItem());
setContextMenu(menu);
}
private boolean isStandIn() {
return getTableRow() != null && getTableRow().getItem() instanceof StandIn;
}
/**
* Update cell's editable based on the rowItem.
*/
private void doUpdateEditable() {
if (isEmpty() || isStandIn()) {
setEditable(false);
} else {
setEditable(true);
}
}
#Override
public void updateItem(String item, boolean empty) {
super.updateItem(item, empty);
doUpdateEditable();
if (isStandIn()) {
if (isEditing()) {
LOG.info("shouldn't be editing - has StandIn");
}
if (button == null) {
button = createButton();
}
setText(null);
setGraphic(button);
}
}
private Button createButton() {
Button b = new Button("Add");
b.setOnAction(e -> {
int index = getTableView().getItems().size() -1;
getTableView().getItems().add(index, createNewItem("button", index));
});
return b;
}
private MenuItem createMenuItem() {
MenuItem item = new MenuItem("Add");
item.setOnAction(e -> {
if (isStandIn()) return;
int index = getIndex();
getTableView().getItems().add(index, createNewItem("menu", index));
});
return item;
}
private S createNewItem(String text, int index) {
return (S) new Person(text + index, text + index, text);
}
}
private Person createNewItem(String text, int index) {
return new Person(text + index, text + index, text);
}
#Override
public void start(Stage primaryStage) throws Exception {
primaryStage.setScene(new Scene(getContent()));
primaryStage.setTitle(FXUtils.version());
primaryStage.show();
}
/**
* Marker-Interface to denote a class as not mutable.
*/
public static interface StandIn {
}
public static class PersonStandIn extends Person implements StandIn{
public PersonStandIn() {
super("standIn", "", "");
}
}
public static void main(String[] args) {
launch(args);
}
#SuppressWarnings("unused")
private static final Logger LOG = Logger
.getLogger(TablePersonAddRowAndEdit.class.getName());
}
Update
shouldn't have been too surprised - a related problem was discussed half a year ago (and produced a bug report)

JDK 8 TreeView disclosure triangle vertical aligned not correctly

I make a custom tree cell which has height 40 px.
And here a problem disclosure triangle does not aligned center vertically.
Here code of tree cell:
public static class TestObjectCell extends AnchorPane implements ISMPBVisualComponentWithData<TestObject>{
public Label label;
public TestObjectCell(){
label=new Label("label");
AnchorPane.setTopAnchor(label, 10.0);
this.getChildren().setAll(label);
this.setMinHeight(40);
this.setPrefHeight(40);
this.setMaxHeight(40);
}
#Override
public void setComponentData(TestObject object) {
//throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}
}
As u can see at picture disclosure triangle aligned at top, how do align him vertical center of cell?
I had the same problem. I used the cell factory to translate the disclosure node of the TreeCell:
myTree.setCellFactory(treeView -> {
final TreeCell<Label> cell = new TreeCell<Label>() {
#Override public void updateItem(Label item, boolean empty) {
super.updateItem(item, empty);
if (empty) {
setGraphic(null);
} else {
final Node graphic = (getTreeItem() == null) ? null : getTreeItem().getGraphic();
setGraphic((graphic != null) ? graphic : (item != null) ? item.getGraphic() : null);
}
setText((empty || item == null) ? null : item.getText());
}
};
cell.disclosureNodeProperty().addListener((obs, oldNode, newNode) -> {
final StackPane pane = (StackPane) newNode;
newNode.translateYProperty().bind(cell.heightProperty().multiply(0.5).subtract(pane.heightProperty()));
});
return cell;
});
Surely there must be a better way to do this, but at least this worked for me.
Have you tried setting alignment property inside TreeCell ?
The only way that I have found to change the alignment of the disclosure node is to manually override the vertical padding using the -fx-padding style:
.tree-disclosure-node {
-fx-padding: 0.85em 0.229em 0.333333em 0.229em;
}
This will allow you to get the arrow centered as needed, but you will need to modify this value if the row height ever changes.

BlackBerry - Custom centered cyclic HorizontalFieldManager

Trying to create a custom cyclical horizontal manager which will work as follows. It will control several field buttons where the buttons will always be positioned so that the focused button will be in the middle of the screen. As it is a cyclical manager once the focus moves to the right or left button, it will move to the center of the screen and all the buttons will move accordingly (and the last button will become the first to give it an cyclic and endless list feeling)
Any idea how to address this?
I tried doing this by implementing a custom manager which aligns the buttons according to the required layout. Each time moveFocus() is called I remove all fields (deleteAll() ) and add them again in the right order.
Unfortunately this does not work.
Using HorizontalButtonFieldSet class from KB How to - Implement advanced buttons, fields, and managers:
class CentricHManager extends HorizontalButtonFieldSet {
int focusedFieldIndex = 0;
public void focusChangeNotify(int arg0) {
super.focusChangeNotify(arg0);
int focusedFieldIndexNew = getFieldWithFocusIndex();
if (focusedFieldIndexNew != focusedFieldIndex) {
if (focusedFieldIndexNew - focusedFieldIndex > 0)
switchField(0, getFieldCount() - 1);
else
switchField(getFieldCount() - 1, 0);
}
}
private void switchField(int prevIndex, int newIndex) {
Field field = getField(prevIndex);
delete(field);
insert(field, newIndex);
}
public void add(Field field) {
super.add(field);
focusedFieldIndex = getFieldCount() / 2;
setFieldWithFocus(getField(focusedFieldIndex));
}
}

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