Update JavaFX nodes in a treeview - treeview

I am starting me in javafx. And I have a problem. I have a treeview where the nodes are changed his position by external command but it just does not see the tree. I have to minimize the parent and re-expand to see the effect.
Altem any suggestions for that treeview can be refreshed as a code.
Exempo the code:
public Boolean SobeNodo()
{
TreeItem<TreeNodo> oNodoSel = this.getSelectionModel().getSelectedItem();
if (oNodoSel != null)
{
TreeItem<TreeNodo> oNodoPai = oNodoSel.getParent();
if (oNodoPai != null)
{
int nIndex = oNodoPai.getChildren().indexOf(oNodoSel);
if (nIndex > 0)
{
oNodoPai.getChildren().removeAll(oNodoSel);
oNodoPai.getChildren().add(nIndex - 1, oNodoSel);
return true;
}
}
}
return false;
}
Sorry for my English and thanks for the time spent.

You encountered an issue in TreeView: http://javafx-jira.kenai.com/browse/RT-20090
For now you can use next workaround (it's actually just a 50ms delay for 2nd operation with tree):
if (nIndex > 0) {
oNodoPai.getChildren().removeAll(oNodoSel);
TimelineBuilder.create().keyFrames(
new KeyFrame(Duration.millis(50), new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent t) {
oNodoPai.getChildren().add(nIndex - 1, oNodoSel);
}
})).build().play();
return true;
}

Related

How to prevent user pressing multiple keys Javafx?

I have a player that can move when pressing the arrow keys. I would like to prevent the user to press multiple arrows at the same time.
This what I have tried:
boolean[] pressedKeys = new boolean[4];
canvas.setOnKeyPressed(event -> {
if (!Arrays.asList(pressedKeys).contains(true)){
if (event.getCode() == KeyCode.UP){
pressedKeys[0] = true;
} else if (event.getCode() == KeyCode.RIGHT){
pressedKeys[1] = true;
} else if (event.getCode() == KeyCode.DOWN){
pressedKeys[2] = true;
} else if (event.getCode() == KeyCode.LEFT){
pressedKeys[3] = true;
}
}
});
canvas.setOnKeyReleased(event -> {
if (event.getCode() == KeyCode.UP){
pressedKeys[0] = false;
} else if (event.getCode() == KeyCode.RIGHT){
pressedKeys[1] = false;
} else if (event.getCode() == KeyCode.DOWN){
pressedKeys[2] = false;
} else if (event.getCode() == KeyCode.LEFT){
pressedKeys[3] = false;
}
});
But it does not work, here I can still press the right and the up arrows for example.
Thanks for any help
I'd create an event handler implementation like this:
class InputHandler implements EventHandler<KeyEvent> {
final private Set<KeyCode> activeKeys = new HashSet<>();
#Override
public void handle(KeyEvent event) {
if (activeKeys.isEmpty() && KeyEvent.KEY_PRESSED.equals(event.getEventType())) {
activeKeys.add(event.getCode());
} else if (KeyEvent.KEY_RELEASED.equals(event.getEventType())) {
activeKeys.remove(event.getCode());
}
}
public Set<KeyCode> getActiveKeys() {
return Collections.unmodifiableSet(activeKeys);
}
}
The check activeKeys.isEmpty() ensures that we don't register a new keypress until a prior key is released.
A single value for the activeKey could be used instead of the activeKeys HashSet, I just adapted this from a prior solution which works in a more general case.
To use it:
InputHandler inputHandler = new InputHandler();
scene.setOnKeyPressed(inputHandler);
scene.setOnKeyReleased(inputHandler);
Then, if it is something like a game where the input is checked on each frame update of an AnimationTimer, in the update method you can check the current active keys for the frame and action them, like this:
private AnimationTimer createGameLoop() {
return new AnimationTimer() {
public void handle(long now) {
update(now, inputHandler.getActiveKeys());
if (isGameOver()) {
this.stop();
}
}
};
I am not sure if your chosen strategy will result in a desirable user experience, you will need to try it out and see how well it works in your application.
I found a solution, thanks to #kleopatra
This is what I made:
boolean pressedKeys = false, releasedKeys = true;
canvas.setOnKeyPressed(event -> {
if (releasedKeys){
// Code goes here
pressedKeys = true;
releasedKeys = false;
}
});
canvas.setOnKeyReleased(event -> {
if (pressedKeys){
pressedKeys = false;
releasedKeys = true;
}
});
Like this, its not possible to press multiple keys at one time

Scroll Index method not firing consistently

In a Xamarin.Forms and Xamarin.Android project I create a Custom Render and Adapter for a ListView.
The adapter implements BaseAdapter and ISectionIndexer. The custom render of this control is using FastScroll feature, in Android when you tap this scroll a bubble with a index letter appears. This works fine, but my idea is to have a way to catch the selected index after releasing scroll and that scroll "bubble" disappears.
I thought with the following class (in the GetSectionForPosition method) could achieve that:
public class ListViewconIndexAdapter : BaseAdapter<string>, ISectionIndexer
{
string[] items;
Activity context;
string[] sections;
Java.Lang.Object[] sectionsObjects;
Dictionary<string, int> alphaIndex;
public ListViewconIndexAdapter(Activity context, string[] items) : base()
{
this.context = context;
this.items = items;
alphaIndex = new Dictionary<string, int>();
for (int i = 0; i < items.Length; i++)
{
var key = items[i][0].ToString();
if (!alphaIndex.ContainsKey(key))
alphaIndex.Add(key, i);
}
sections = new string[alphaIndex.Keys.Count];
alphaIndex.Keys.CopyTo(sections, 0);
sectionsObjects = new Java.Lang.Object[sections.Length];
for (int i = 0; i < sections.Length; i++)
{
sectionsObjects[i] = new Java.Lang.String(sections[i]);
}
}
public override Java.Lang.Object GetItem(int position)
{
return position;
}
public override long GetItemId(int position)
{
return position;
}
public override string this[int position]
{
get { return items[position]; }
}
public override View GetView(int position, View convertView, ViewGroup parent)
{
View view = convertView;
if (view == null)
view = context.LayoutInflater.Inflate(Android.Resource.Layout.SimpleListItem1, null);
view.FindViewById<TextView>(Android.Resource.Id.Text1).Text = items[position];
return view;
}
//Fill in cound here, currently 0
public override int Count
{
get { return items.Length; }
}
// -- ISectionIndexer --
public int GetPositionForSection(int section)
{
return alphaIndex[sections[section]];
}
public int GetSectionForPosition(int position)
{ // this method isn't called in this example, but code is provided for completeness
int prevSection = 0;
for (int i = 0; i < sections.Length; i++)
{
if (GetPositionForSection(i) > position)
{
break;
}
prevSection = i;
}
Console.WriteLine(prevSection);
Console.WriteLine(sections[prevSection]);
//Toast.MakeText(context, sections[prevSection], ToastLength.Short).Show();
Xamarin.Forms.MessagingCenter.Send<object,string>(this, "CambioSeccion", sections[prevSection]);
return prevSection;
}
}
I put those Console.writeline for checking the index letter and that Message send is a way to send it back to PCL/NET Standard code (to show an DisplayAlert or something).
But the problem is that method firing is not consistent, for example, sometimes you fast scroll down to 'C' but Console doesn't print anything after releasing it there, but after touching it again where you leave it, it fires up. But sometimes it works like i want, it prints after release the scroll at selected index.
ListView has two different scroll listeners, AbsListView.IOnScrollListener and AbsListView.IOnScrollChangeListener (this one was added in API 23) and a touch listener (AbsListView.IOnTouchListener)
I think based upon your use-case, you are looking for the OnScrollStateChanged and when it goes into idle state and you are not touching the listview, do something (or vice versa).
Example (adjust to your needs of course):
public class MyScrollListener : Java.Lang.Object, AbsListView.IOnTouchListener, AbsListView.IOnScrollListener, AbsListView.IOnScrollChangeListener //(API23)
{
bool touching;
bool scrolling;
public void OnScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount)
{
}
public void OnScrollChange(View v, int scrollX, int scrollY, int oldScrollX, int oldScrollY)
{
}
public void OnScrollStateChanged(AbsListView view, [GeneratedEnum] ScrollState scrollState)
{
switch(scrollState)
{
case ScrollState.Idle:
if (!touching)
{
scrolling = false;
GetSelection();
}
break;
default:
scrolling = true;
break;
}
}
public bool OnTouch(View v, MotionEvent e)
{
switch (e.Action)
{
case MotionEventActions.Up:
touching = false;
if (!scrolling)
GetSelection();
break;
default:
touching = true;
break;
}
return true;
}
void GetSelection()
{
// touch and srolling is done, do something
}
}
Usage:
var scrollListener = new MyScrollListener();
listView.SetOnTouchListener(scrollListener);
listView.SetOnScrollListener(scrollListener);
listView.SetOnScrollChangeListener(scrollListener); // API23

Windows Form Multi-Select for Tree View

Is there a way to multi-select in a Windows Tree View? Similar to the image below
I know that .NET currently doesn't have a multiselect treeview. It is treated as a wrapper around the win32 native treeview control. I would like to avoid the Treeview's Checkbox property if possible. Any suggestions is greatly appreciated!
Im gonna assume you're trying to avoid check boxes. Here is an example:
public partial class Form1 : Form {
public Form1() {
InitializeComponent();
treeView1.DrawMode = OwnerDrawText;
treeView1.DrawNode += treeView1_DrawNode;
treeView1.NodeMouseClick += treeView1_NodeMouseClick;
}
private void treeView1_DrawNode(object sender, DrawTreeNodeEventArgs e) {
// Show checked nodes with an underline
using (SolidBrush br = new SolidBrush(e.Node.TreeView.BackColor))
e.Graphics.FillRectangle(br, e.Node.Bounds);
Font nodeFont = e.Node.NodeFont;
if (nodeFont == null) nodeFont = e.Node.TreeView.Font;
if (e.Node.Checked) nodeFont = new Font(nodeFont, FontStyle.Underline);
using (SolidBrush br = new SolidBrush(e.Node.TreeView.ForeColor))
e.Graphics.DrawString(e.Node.Text, nodeFont, br, e.Bounds);
if (e.Node.Checked) nodeFont.Dispose();
}
private void treeView1_NodeMouseClick(object sender, TreeNodeMouseClickEventArgs e) {
if (Control.ModifierKeys == Keys.Shift && e.Node.Parent != null) {
// Extend selection
bool check = false;
foreach (TreeNode node in e.Node.Parent.Nodes) {
if (node.Checked) check = true;
node.Checked = check;
if (node == e.Node) break;
}
}
else {
unselectNodes(treeView1.Nodes);
e.Node.Checked = true;
}
}
This question has been answered here but I'll briefly answer your question. While it is true that Native Treeview control does not allow multiple selection, you can derive a subclass from it and override its behaviors.
Example code:
checkNodes method:
private void checkNodes(TreeNode node, bool check)
{
foreach (TreeNode child in node.Nodes)
{
if (child.Checked == true)
{
MessageBox.Show(child.Text);
}
//MessageBox.Show(child.Text);
checkNodes(child, check);
}
}
Treeview method after check:
private void treeView1_AfterCheck(object sender, TreeViewEventArgs e)
{
if (e.Action != TreeViewAction.Unknown)
{
if (busy) return;
busy = true;
try
{
TreeNode _node = e.Node;
checkNodes(e.Node, e.Node.Checked);
if (e.Node.Checked)
{
MessageBox.Show(e.Node.Text);
}
}
finally
{
busy = false;
}
}
}
It is not trivial to do so, however it can be done.

Vala GTK+. Issue with customized widget

I need to create a gtk.Entry which accepts only numbers. but I can't overwrite the key_press_event event in an heredited class. It only works if I use the original Entry by means of connect function.
What am I doing wrong?
using Gtk;
public class NumberEntry : Entry {
public void NumberEntry(){
add_events (Gdk.EventMask.KEY_PRESS_MASK);
}
//With customized event left entry editing is not possible
public override bool key_press_event (Gdk.EventKey event) {
string numbers = "0123456789.";
if (numbers.contains(event.str)){
return false;
} else {
return true;
}
}
}
public class Application : Window {
public Application () {
// Window
this.title = "Entry Issue";
this.window_position = Gtk.WindowPosition.CENTER;
this.destroy.connect (Gtk.main_quit);
this.set_default_size (350, 70);
Grid grid = new Grid();
grid.set_row_spacing(8);
grid.set_column_spacing(8);
Label label_1 = new Label ("Customized Entry, useless:");
grid.attach (label_1,0,0,1,1);
//Customized Entry:
NumberEntry numberEntry = new NumberEntry ();
grid.attach(numberEntry, 1, 0, 1, 1);
Label label_2 = new Label ("Working only numbers Entry:");
grid.attach (label_2,0,1,1,1);
//Normal Entry
Entry entry = new Entry();
grid.attach(entry, 1, 1, 1, 1);
this.add(grid);
//With normal Entry this event works well:
entry.key_press_event.connect ((event) => {
string numbers = "0123456789.";
if (numbers.contains(event.str)){
return false;
} else {
return true;
}
});
}
}
public static int main (string[] args) {
Gtk.init (ref args);
Application app = new Application ();
app.show_all ();
Gtk.main ();
return 0;
}
The key_press_event of the superclass is no longer being called. You need to call the base class and return true when you have consumed the key.
public override bool key_press_event (Gdk.EventKey event) {
string numbers = "0123456789.";
if (numbers.contains(event.str)){
return base.key_press_event (event);
} else {
return true;
}
}
If you return false in a signal, this can be passed to an alternate handler, but only if you use connect and not override the signal method.

Adding animation to a button in BlackBerry

I want to use animation on a Button that I created in my BlackBerry App. The animation works fine the first time when I click the button. On first click, the button starts animation (blinking). On second click the blinking stops. However, when I click the button again (third time), the blinking should start again. However, I get an error:
App Error 104 Uncaught: IllegalStateException
The code for creating the Button and adding animation is as follows:
final Bitmap image000 = Bitmap.getBitmapResource("panic.png");
final Bitmap image001 = Bitmap.getBitmapResource("panicon.png");
final Timer animationTimer = new Timer();
final BitmapField animationField = new BitmapField(image000,BitmapField.FOCUSABLE){
protected boolean navigationClick(int status, int time)
{
if(flag){
animationTask.cancel();
flag=false;
}else{
animationTimer.scheduleAtFixedRate(animationTask, 0, 100);
flag=true;
}
return true;
}
};
animationTask = new TimerTask() {
public void run() {
if(counter == 0){
animationField.setBitmap(image000);
}
if(counter == 1){
animationField.setBitmap(image001);
counter = -1;
}
counter++;
}
};
add(animationField);
EDIT: I debugged my code and the error occurs in the loop that starts the thread. Cancelling the thread seems fine. I am lost what is the issue. Please guide.
try this -
TimerTask animationTask;
BitmapField animationField;
final Bitmap image000 = Bitmap.getBitmapResource("panic.png");
final Bitmap image001 = Bitmap.getBitmapResource("panicon.png");
final Timer animationTimer = new Timer();
animationField = new BitmapField(image000,BitmapField.FOCUSABLE){
protected boolean navigationClick(int status, int time)
{
if(flag){
animationTask.cancel();
flag=false;
}else{
animationTask = new TimerTask() {
public void run() {
if(counter == 0){
animationField.setBitmap(image000);
}
if(counter == 1){
animationField.setBitmap(image001);
counter = -1;
}
counter++;
}
};
animationTask.run();
animationTimer.scheduleAtFixedRate(animationTask, 0, 100);
flag=true;
}
return true;
}
};
animationTask = new TimerTask() {
public void run() {
if(counter == 0){
animationField.setBitmap(image000);
}
if(counter == 1){
animationField.setBitmap(image001);
counter = -1;
}
counter++;
}
};
add(animationField);

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