i have one choicebox in javafx contains 3 items let A B and C so on change of selection of this item i want to perform certain task so how can i handle this events?
final ChoiceBox cmbx=new ChoiceBox();
try {
while(rs.next())
{
cmbx.getItems().add(rs.getString(2));
}
}
catch (SQLException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
im adding items to choicebox from database...
now i want to know how to handle the events of choicebox in javafx
Add a ChangeListener to the ChoiceBox's selectionmodel and selectedIndexProperty:
final ChoiceBox<String> box = new ChoiceBox<String>();
box.getItems().add("1");
box.getItems().add("2");
box.getItems().add("3");
box.getSelectionModel().selectedIndexProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observableValue, Number number, Number number2) {
System.out.println(box.getItems().get((Integer) number2));
}
});
Sebastian explained well enough though, just incase if you have interest only on actual value selected on the choice box and doesn't much care about index, then you can just use selectedItemProperty instead of selectedIndexProperty.
Also ChangeListener is functional interface, you can use lambda here when you go with java 8. I just little bit modified Sebastian's example. The newValue is newly selected value.
ChoiceBox<String> box = new ChoiceBox<String>();
box.getItems().add("1");
box.getItems().add("2");
box.getItems().add("3");
box.getSelectionModel()
.selectedItemProperty()
.addListener( (ObservableValue<? extends String> observable, String oldValue, String newValue) -> System.out.println(newValue) );
I know this is an old question, but a simpler way of doing it is using ChoiceBox.setOnAction(EventHandler):
ChoiceBox<String> box = ...;
box.setOnAction(event -> {
System.out.println(box.getValue());
});
or in FXML:
<ChoiceBox fx:id="id" onAction="#controllerMethod">
Related
How to create field variable automatically when I create method used that field. I've create template like this:
void $METHOD_NAME$() {
$FIELD_NAME$ = true;
}
when I type field name (e.g. mState) in method will create field as:
private boolean mState = false;
Hope someone help. Sorry my bad.
Given the screenshot of your template, you can also create a field with the following live template:
private boolean $param$ = false;
#Override
public void onBackPressed() {
if ($param$) super.onBackPressed();
android.widget.Toast.makeText(this, "$message$",
android.widget.Toast.LENGTH_SHORT).show();
$param$ = true;
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
$param$ = false;
}
}, 100);
}
Where $param$ and $message$ are regular variables without anything special.
However, like I said in the comment on your question, I suggest to split it up in several smaller templates.
Consider to split it up in:
field + method with just:
private boolean $param$ = false;
#Override
public void onBackPressed() {
if ($param$) super.onBackPressed();
$param$ = true;
}
Then create a template for the message:
android.widget.Toast.makeText(this, "$message$", android.widget.Toast.LENGTH_SHORT).show();
And last but not least, create a template for the postDelayed:
final Handler handler = new Handler();
handler.postDelayed(new Runnable() {
#Override
public void run() {
$END$
}
}, $delay$);
Note: the $delay$ as a bonus you can even give it a default value or create a list of predefined values for ease of use.
Note2: Instead of $param$ = false; I've replaced it with $END$. This will position your cursor here once you've selected the delay. Now you can type mState = false manually here, or whatever code you need in the context at that moment. This makes the template much more flexible and easier to use.
PS. I suppose you want to call super.onBackPressed() only when the value is false (on the first invocation). In that case use if (!$param$) instead.
// Update:
In order to group the newly added field with the other fields and not halfway somewhere in your class between other methods, rearrange the code
via the menu with: Code -> rearrange code.
To customise this, check your arrangement settings under: settings -> code style -> <language> -> arrangement
I have method
public override void InitializeRow(object sender, InitializeRowEventArgs e)
{
if (!e.ReInitialize)
Task.Factory.StartNew(() =>
{
AfterInitializeRow(sender, e);
});
}
public override void AfterInitializeRow(object sender, InitializeRowEventArgs e)
{
foreach (UltraGridColumn ugc in e.Row.Band.Columns)
{
if (IsNumeric(ugc.Key))
{
e.Row.Cells[ugc].DroppedDown = true;
e.Row.Cells[ugc].ValueList = “Some value”;
e.Row.Cells[ugc].SetValue(e.Row.Cells[ugc.Key].Value, false);
e.Row.Cells[ugc].Style = Infragistics.Win.UltraWinGrid.ColumnStyle.DropDownList;
}
}
}
But its Giving error at e.Row.Cells[ugc].DroppedDown = true;
I learned that only Main thread can update the UI.
But is it possible that while updating the DroppedDown only it switch to main thread. Bcoz more than 1000’s rows are initialized in this way making the load of Grid very slow. So I want to do some kind of parallelism in this process.
In any function in your Form or UserControl, you can use the following type of code:
public void SetText(string text)
{
if (InvokeRequired)
{
BeginInvoke(new Action<string>(SetText), text);
}
else
{
label1.Text = text;
}
}
label1 would be the control to update in this case.
This will make sure that you invoke the function on the UI-thread.
You should still be careful with syncrhonization, though, but simply updating your UI from another thread can be easily done like that.
The answer to this question is that you shouldn't be using threading in the InitialzieRow event to set or even access properties on the grid or its related objects.
What you should do instead is look for ways to optimize what you are doing in this method first. For example why are you setting the value of a cell to the value it already has, this line of code should be able to be removed without impacting behavior.
Also all of the logic provided is only based on the column key so if the column has a consistent set of values, you could set the ValueList on the column in InitializeLayout instead of using InitializeRow.
I am trying to do per-keystroke validation in a JavaFX TextFieldTableCell but I do not know how to capture the text-changed events from the embedded TextField control.
If the object in question were simply a TextField, then textField.textProperty().addListener(myChangeListener) would do the trick. TextFieldTableCell also exposes textProperty(), but this property behaves quite differently on TextFieldTableCell. It does not generate change events on a per-keystroke basis. Rather, I see lots of events when the TableView is first displayed, and I see one event each time I begin editing in a cell.
First of all, about textProperty().
Look here to see :
http://docs.oracle.com/javafx/2/api/index.html
TextProperty() is a property of labeled parent class, you will learn nothing from it, because it is not used. It is tricky thing : cell - inheritant of labeled control. TextField, which you see, when start editing, it is a graphic node of cell (graphicProperty()) (as far as I remember documentation).
And, this graphic node is assigned by a text field, only when editing starts.
AFAIK, there is no direct access to editable node.
The way to solve the issue - implement editable cell by your self.
Let me talk to developer, to learn more...
Supposing, you have DataItem class, which contains String, and supposing that TableView has encapsulated data type DataItem, and the only column has the same encapsulated data type, you may use this implementation as basis :
public class TextFieldTableCell extends TableCell<DataItem, DataItem> {
private TextField textField;
public TextFieldTableCell() {
}
#Override
public void startEdit() {
super.startEdit();
if (isEmpty()) {
return;
}
if (textField == null) {
createTextBox();
} else {
textField.setText(new CellCustomStringConverter().toString(getItem()));
}
setGraphic(textField);
setContentDisplay(ContentDisplay.GRAPHIC_ONLY);
textField.requestFocus();
textField.selectAll();
}
#Override
public void cancelEdit() {
super.cancelEdit();
setContentDisplay(ContentDisplay.TEXT_ONLY);
}
#Override
public void updateItem(DataItem item, boolean empty) {
super.updateItem(item, empty);
if (!isEmpty()) {
if (textField != null) {
textField.setText(new CellCustomStringConverter().toString(item));
}
setText(item.toString());
}
}
private void createTextBox() {
textField = new TextField(new CellCustomStringConverter().toString(getItem()));
textField.setId(TABLE_EDIT_ID);
textField.setOnKeyReleased(new EventHandler<KeyEvent>() {
#Override
public void handle(KeyEvent t) {
if (t.getCode() == KeyCode.ENTER) {
commitEdit(new DataItem(textField.getText()));
} else if (t.getCode() == KeyCode.ESCAPE) {
cancelEdit();
}
}
});
}
}
Is there anyway to define the editor type on a cell by cell basis in GXT 3.0?
I need to create a transposed table; the column become the row and the row is the column. That being the case, a column (from a normal table point of view) will have various editor type, whereby a row will have identical editor type.
I am trying to use following approach - It seems to be working fine, and allow to open up editors based on data type but when i click out; it doesn't close/hide editor.
I would really appreciate if someone can please point me in right direction.
final GridInlineEditing<MyModel> editing = new GridInlineEditing<MyModel>(mygrid){
#SuppressWarnings("unchecked")
#Override public <O> Field<O> getEditor(ColumnConfig<MyModel, ?> columnConfig) {
if(valueColumnName.equals(columnConfig.getHeader().asString())) {
MyModel myModel = tree.getSelectionModel().getSelectedItem();
if(MyModelType.STRING.equals(myModel.getMyModelType())) {
TextField textField = new TextField();
textField.setAllowBlank(Boolean.FALSE);
return (Field<O>) textField;
}
else {
TextArea textField = new TextArea();
textField.setAllowBlank(Boolean.FALSE);
return (Field<O>) textField;
}
}
return super.getEditor(columnConfig);
}
};
editing.setClicksToEdit(ClicksToEdit.TWO);
PS:
This is similar to question below; but answer is specific to post GXT 3.0. I am new to stackoverflow and it seems recommendation was to create new question instead of adding new post to old thread.
GXT EditorGrid: choose cell editor type on a cell by cell basis
After playing around all day; my colleague(Praveen) and I figured it out. So instead of trying to override GridInlineEditing's getEditor() method override startEditing() method. Also, you will need converters if you have data like Date, List etc. Below is sample code; hope this help others.
final GridInlineEditing<MyModel> editing = new GridInlineEditing<MyModel>(tree){
#Override public void startEditing(GridCell cell) {
MyModel myModel= tree.getSelectionModel().getSelectedItem();
if(MyModelType.TEXT.equals(myModel.getContextVariableType())) {
TextArea textField = new TextArea();
textField.setAllowBlank(Boolean.FALSE);
super.addEditor(valueColumn, textField);
}
else if(MyModelType.BOOLEAN.equals(myModel.getContextVariableType())) {
SimpleComboBox<String> simpleComboBox = new SimpleComboBox<String>(new StringLabelProvider<String>());
simpleComboBox.setTriggerAction(TriggerAction.ALL);
simpleComboBox.add("YES");
simpleComboBox.add("NO");
super.addEditor(valueColumn, simpleComboBox);
}
else if(MyModel.INTEGER.equals(myModel.getContextVariableType())) {
SpinnerField<Integer> spinnerField = new SpinnerField<Integer>(new IntegerPropertyEditor());
spinnerField.setIncrement(1);
Converter<String, Integer> converter = new Converter<String, Integer>(){
#Override public String convertFieldValue(Integer object) {
String value = "";
if(object != null) {
value = object.toString();
}
return value;
}
#Override public Integer convertModelValue(String object) {
Integer value = 0;
if(object != null && object.trim().length() > 0) {
value = Integer.parseInt(object);
}
return value;
}
};
super.addEditor(valueColumn, converter, (Field)spinnerField);
}
else {
TextField textField = new TextField();
textField.setAllowBlank(Boolean.FALSE);
super.addEditor(valueColumn, textField);
}
super.startEditing(cell);
}
};
editing.setClicksToEdit(ClicksToEdit.TWO);
I think the reason you are not seeing the fields not closing is because you are not actually adding them to the GridInlineEditing class.
In the parts where you have the following return statements;
return (Field<O>) textField;
Those textfields are never added to the grid.
I would try substituting the following code for your first two return statement;
super.addEditor(columnConfig, (Field<O>) textField;
This adds the editor to some maps used by AbstractGridEditing. Specifically, the AbstractGridEditing.removeEditor(GridCell, Field<?>) method, which is used in GridInlineEditing.doCompleteEditing() and GridInlineEditing.cancelEditing() needs the field to be in the map so it can be detached from its parent.
so i'm trying to set up an application where i have multiple panels inside a jframe. lets say 3 of them are purely for display purposes, and one of them is for control purposes. i'm using a borderLayout but i don't think the layout should really affect things here.
my problem is this: i want the repainting of the three display panels to be under the control of buttons in the control panel, and i want them to all execute in sync whenever a button on the control panel is pressed. to do this, i set up this little method :
public void update(){
while(ButtonIsOn){
a.repaint();
b.repaint()
c.repaint();
System.out.println("a,b, and c should have repainted");
}
}
where a,b, and c are all display panels and i want a,b,and c to all repaint continously until i press the button again. the problem is, when i execute the loop, the message prints in an infinite loop, but none of the panels do anything, ie, none of them repaint.
i've been reading up on the event dispatch thread and swing multithreading, but nothing i've found so far has really solved my problem. could someone give me the gist of what i'm doing wrong here, or even better, some sample code that handles the situation i'm describing? thanks...
The java.util.concurrent package provides very powerful tools for concurrent programing.
In the code below, I make use of a ReentrantLock (which works much like the Java synchronized keyword, ensuring mutually exclusive access by multiple threads to a single block of code). The other great thing which ReentrantLock provides are Conditions, which allow Threads to wait for a particular event before continuing.
Here, RepaintManager simply loops, calling repaint() on the JPanel. However, when toggleRepaintMode() is called, it blocks, waiting on the modeChanged Condition until toggleRepaintMode() is called again.
You should be able to run the following code right out of the box. Pressing the JButton toggle repainting of the JPanel (which you can see working by the System.out.println statements).
In general, I'd highly recommend getting familiar with the capabilities that java.util.concurrent offers. There's lots of very powerful stuff there. There's a good tutorial at http://docs.oracle.com/javase/tutorial/essential/concurrency/
import java.awt.Component;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Collection;
import java.util.Collections;
import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.ReentrantLock;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class RepaintTest {
public static void main(String[] args) {
JFrame frame = new JFrame();
JPanel panel = new JPanel()
{
#Override
public void paintComponent( Graphics g )
{
super.paintComponent( g );
// print something when the JPanel repaints
// so that we know things are working
System.out.println( "repainting" );
}
};
frame.add( panel );
final JButton button = new JButton("Button");
panel.add(button);
// create and start an instance of our custom
// RepaintThread, defined below
final RepaintThread thread = new RepaintThread( Collections.singletonList( panel ) );
thread.start();
// add an ActionListener to the JButton
// which turns on and off the RepaintThread
button.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
thread.toggleRepaintMode();
}
});
frame.setSize( 300, 300 );
frame.setVisible( true );
}
public static class RepaintThread extends Thread
{
ReentrantLock lock;
Condition modeChanged;
boolean repaintMode;
Collection<? extends Component> list;
public RepaintThread( Collection<? extends Component> list )
{
this.lock = new ReentrantLock( );
this.modeChanged = this.lock.newCondition();
this.repaintMode = false;
this.list = list;
}
#Override
public void run( )
{
while( true )
{
lock.lock();
try
{
// if repaintMode is false, wait until
// Condition.signal( ) is called
while ( !repaintMode )
try { modeChanged.await(); } catch (InterruptedException e) { }
}
finally
{
lock.unlock();
}
// call repaint on all the Components
// we're not on the event dispatch thread, but
// repaint() is safe to call from any thread
for ( Component c : list ) c.repaint();
// wait a bit
try { Thread.sleep( 50 ); } catch (InterruptedException e) { }
}
}
public void toggleRepaintMode( )
{
lock.lock();
try
{
// update the repaint mode and notify anyone
// awaiting on the Condition that repaintMode has changed
this.repaintMode = !this.repaintMode;
this.modeChanged.signalAll();
}
finally
{
lock.unlock();
}
}
}
}
jComponent.getTopLevelAncestor().repaint();
You could use SwingWorker for this. SwingWorker was designed to perform long running tasks in the background without blocking the event dispatcher thread. So, you need to extend SwingWorker and implement certain methods that will make sense to you. Note that all long running action should happen in the doInBackground() method, and the Swing UI elements should be updated only on the done() method.
So here is an example :
class JPanelTask extends SwingWorker<String, Object>{
JPanel panel = null;
Color bg = null;
public JPanelTask(JPanel panel){
this.panel = panel;
}
#Override
protected String doInBackground() throws Exception {
//loooong running computation.
return "COMPLETE";
}
#Override
protected void done() {
panel.repaint();
}
}
Now, in your "control" button's action performed event, you could do the following :
controlButton.addActionListener(new ActionListener() {
#Override
public void actionPerformed(ActionEvent arg0) {
JPanelTask task1 = new JPanelTask(panel1);
task1.execute();
JPanelTask task2 = new JPanelTask(panel2);
task2.execute();
//so on..
}
});
Another way is using javax.swing.Timer. Timer helps you to fire a change to your ui elements in a timely fasthion.This may not be the most appropriate solution. But it gets the work done too.
Again you should be careful about updating UI elements in right places.