I want to display the height of a borderpane. I added this listener:
mainPane.heightProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observableValue, Number oldSceneHeight, Number newSceneHeight) {
System.out.println("Height: " + newSceneHeight);
}
});
I would like to print the size continuously but unfortunately I get the size only once when I resize the stage.
Related
Is there a way that I can for example make an ImageView to appear only after an InputEditText is not null? So before the InputEditText has some value, ImageView will not appear (hidden or invisible).
Of course.
in the image view's xml add the attribute:
android:visibility="gone"
or
android:visibility="invisible"
to make it invisible by default
You can see a demonstration of the difference between the two, here: http://tips.androidgig.com/invisible-vs-gone-view-in-android/#:~:text=This%20view%20is%20invisible%2C%20and,what%20is%20the%20actual%20difference.
Create a listener in your activity's onCreate() method, to track changes in your InputEditText, and change the visibility of your imageView, based on the text in your input
assuming your InputEditText view ID is "myInput", and your ImageView view ID is "myImage":
InputEditText myInput = findViewById(R.id.myInput);
myInput.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {}
#Override
public void beforeTextChanged(CharSequence s, int start,
int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start,
int before, int count) {
if(s.length() != 0){
ImageView myImage= findViewById(R.id.myImage);
myImage.setVisibility(View.VISIBLE);
}
}
});
I am learning custom views in android.
I made one custom view, with a rectangle and a text. The code of the custom view is:
public class TileGenerator extends View {
// rectangle parameters
private Rect rect = new Rect();
private Paint rectPaint = new Paint();
private Integer rectEndX;
private Integer rectEndY;
private Integer rectStartX;
private Integer rectStartY;
private Integer rectFillColor;
private Float rectTextStartX;
private Float rectTextStartY;
//rectangle text
private String rectText;
private Paint rectTextPaint = new Paint();
public TileGenerator(Context context) {
super(context);
}
#Override
protected void onAttachedToWindow() {
super.onAttachedToWindow();
}
#Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
public void setTileTitleText(String rectText) {
this.rectText = rectText;
}
#Override
protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
super.onLayout(changed, left, top, right, bottom);
rectEndX = getrectEndX();
rectEndY = getrectEndY();
rectStartX = getRectStartX();
rectStartY = getRectStartY();
rectTextStartX = rectEndX/4f + rectStartX;
rectTextStartY = 3.5f * rectEndY/4f + rectStartY;
rectTextPaint.setTextSize(rectEndY/8);
rectTextPaint.setColor(Color.BLACK);
rect.set(rectStartX,rectStartY,rectEndX,rectEndY);
rectPaint.setColor(getRectFillColor());
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawRect(rect, rectPaint);
canvas.drawText(rectText,rectTextStartX,rectTextStartY,rectTextPaint );
}
#Override
protected void onDetachedFromWindow() {
super.onDetachedFromWindow();
}
public Integer getrectEndX() {
return rectEndX;
}
public void setrectEndX(Integer rectEndX) {
this.rectEndX = rectEndX;
}
public Integer getrectEndY() {
return rectEndY;
}
public void setrectEndY(Integer rectEndY) {
this.rectEndY = rectEndY;
}
public Integer getRectStartX() {
return rectStartX;
}
public void setRectStartX(Integer rectStartX) {
this.rectStartX = rectStartX;
}
public Integer getRectStartY() {
return rectStartY;
}
public void setRectStartY(Integer rectStartY) {
this.rectStartY = rectStartY;
}
public Integer getRectFillColor() {
return rectFillColor;
}
public void setRectFillColor(Integer rectFillColor) {
this.rectFillColor = rectFillColor;
}
public String getRectText() {
return rectText;
}
}
After that I created an blank activity. I am doing all with JAVA code. No XML. Then I try to add above custom view to a gridview layout. I want to add two custom views with different text in a horizontal gridview. So far my code is as below:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
GridLayout gridLayout = new GridLayout(this);
// first custom view
CustomRectWithText customRectWithText = new CustomRectWithText(this);
customRectWithText.setRectEndX(200);
customRectWithText.setRectEndY(200);
customRectWithText.setRectStartX(2);
customRectWithText.setRectStartY(2);
customRectWithText.setImage(image);
customRectWithText.setRectText("Text");
customRectWithText.setRectFillColor(Color.BLUE);
gridLayout.addView(customRectWithText);
// second custom view
CustomRectWithText customRectWithText1 = new CustomRectWithText(this);
customRectWithText1.setRectEndX(400);
customRectWithText1.setRectEndY(200);
customRectWithText1.setRectStartX(200 + 5);
customRectWithText1.setRectStartY(2);
customRectWithText1.setTileTitleText("Text 1");
customRectWithText1.setRectFillColor(Color.GREEN);
gridLayout.addView(customRectWithText1);
setContentView(gridLayout);
}
But still I am not getting both of the rectangles in a grid view. Only one rectangle is displayed at a time. In above case only first custom view is displayed.
Where am I doing wrong.
All I want is to make a repetitive rectangle of varying labels of any size inside a grid view.
Is this the way to do it. I mean is there any other way around.
I dont want to use ListItems.
Sorry but i do not have enough repo to comment.
But why dont you make an adapter?
Gridview behaves same as listView.
Use adapter to fill your grid.
This is the proper way to populate listView and gridView also.
I have some signal processing data which gets fed at roughly at 50Hz. I need to update a rectangle's opacity based on the signal value in real time. I am trying to develop the UI in JavaFX 8.
For time being I am simulating the signal value using random number generator in JavaFX service in my code.
I am using Platform.runLater to update the UI, however this doesn't update values in real time, I read through similar problems encountered by others and the normal suggestion is that not to call Platform.runLater often but to batch the updates.
In my case if I batch my updates, the frequency at which the opacity changes will not be equal to the signal frequency.
Any thoughts on how to achieve this?
public class FlickerController
{
#FXML
private Rectangle leftBox;
#FXML
private Rectangle rightBox;
#FXML
private ColorPicker leftPrimary;
#FXML
private ColorPicker leftSecondary;
#FXML
private ColorPicker rightPrimary;
#FXML
private ColorPicker rightSecondary;
#FXML
private Slider leftFrequency;
#FXML
private Slider rightFrequency;
#FXML
private Button startButton;
#FXML
private Label leftfreqlabel;
#FXML
private Label rightfreqlabel;
#FXML
private Label rightBrightness;
#FXML
private Label leftBrightness;
private boolean running = false;
DoubleProperty leftopacity = new SimpleDoubleProperty(1);
DoubleProperty rightopacity = new SimpleDoubleProperty(1);
private FlickerThread ftLeft;
private FlickerThread ftRight;
public void initialize()
{
leftopacity.addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observable,
Number oldValue, Number newValue)
{
Platform.runLater(new Runnable()
{
#Override
public void run()
{
double brightness = leftopacity.doubleValue();
leftBrightness.setText(""+brightness);
leftBox.opacityProperty().set(brightness);
}
});
}
});
rightopacity.addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observable,
Number oldValue, Number newValue)
{
Platform.runLater(new Runnable()
{
#Override
public void run()
{
double brightness = rightopacity.doubleValue();
rightBrightness.setText(""+brightness);
rightBox.opacityProperty().set(brightness);
}
});
}
});
startButton.setOnAction(new EventHandler<ActionEvent>() {
#Override
public void handle(ActionEvent event)
{
if(running)
{
synchronized(this)
{
running=false;
}
startButton.setText("Start");
}
else
{
running=true;
ftLeft = new FlickerThread((int)leftFrequency.getValue(),leftopacity);
ftRight = new FlickerThread((int)rightFrequency.getValue(), rightopacity);
try
{
ftLeft.start();
ftRight.start();
}
catch(Throwable t)
{
t.printStackTrace();
}
startButton.setText("Stop");
}
}
});
leftFrequency.valueProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observable,
Number oldValue, Number newValue)
{
leftfreqlabel.setText(newValue.intValue()+"");
}
});
rightFrequency.valueProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> observable,
Number oldValue, Number newValue)
{
rightfreqlabel.setText(newValue.intValue()+"");
}
});
}
class FlickerThread extends Service<Void>
{
private long sleeptime;
DoubleProperty localval = new SimpleDoubleProperty(1) ;
public FlickerThread(int freq, DoubleProperty valtoBind)
{
this.sleeptime = (1/freq)*1000;
valtoBind.bind(localval);
}
#Override
protected Task <Void>createTask()
{
return new Task<Void>() {
#Override
protected Void call() throws Exception
{
while(running)
{
double val = Math.random();
System.out.println(val);
localval.setValue(val);
Thread.sleep(sleeptime);
}
return null;
}
};
}
}
}
class FlickerThread extends Thread
{
private long sleeptime;
final AtomicReference<Double> counter = new AtomicReference<>(new Double(-1.0));
private Label label;
private Rectangle myrect;
public FlickerThread(int freq, Label label,Rectangle rect)
{
this.sleeptime = (long) ((1.0/freq)*1000.0);
System.out.println("Sleep time is "+sleeptime);
this.label = label;
this.myrect = rect;
}
#Override
public void run() {
double count = 1.0 ;
while (running) {
count = Math.random();
if (counter.getAndSet(count) == -1) {
updateUI(counter, label,myrect);
try
{
Thread.sleep(sleeptime);
} catch (InterruptedException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
}
}
private void updateUI(final AtomicReference<Double> counter,
final Label label, final Rectangle myrect) {
Platform.runLater(new Runnable() {
#Override
public void run() {
double val = counter.getAndSet(-1.0);
final String msg = String.format("Brt: %,f", val);
label.setText(msg);
myrect.opacityProperty().set(val);
}
});
}
You have a calculation error in your code.
Consider:
1/100*1000=0
But:
1.0/100*1000=10.0
i.e. you need to use floating point arithmetic, not integer arithmetic.
There are numerous other issues with your code as pointed out in my previous comment, so this answer is more of a code review and suggested approach than anything else.
You can batch updates to runLater as in James's answer to Throttling javafx gui updates. But for an update rate of 100 hertz max, it isn't going to make a lot of difference performance-wise as JavaFX generally operates on a 60 hertz pulse cycle, unless you really overload it (which you aren't really doing in your example). So the savings you get by throttling updates will be pretty minimal.
Here is a sample you can try out (it uses James's input throttling technique):
import javafx.application.*;
import javafx.beans.property.DoubleProperty;
import javafx.concurrent.Task;
import javafx.geometry.Insets;
import javafx.scene.Scene;
import javafx.scene.control.*;
import javafx.scene.layout.*;
import javafx.scene.paint.Color;
import javafx.scene.shape.Rectangle;
import javafx.stage.Stage;
import java.util.Random;
import java.util.concurrent.atomic.AtomicLong;
public class InputApp extends Application {
private final ToggleButton controlButton = new ToggleButton("Start");
private final Rectangle box = new Rectangle(100, 100, Color.BLUE);
private final Label brightness = new Label();
private final Label frequencyLabel = new Label();
private final Slider frequency = new Slider(1, 100, 10);
private InputTask task;
#Override
public void start(Stage stage) throws Exception {
// initialize bindings.
brightness.textProperty().bind(
box.opacityProperty().asString("%.2f")
);
frequencyLabel.textProperty().bind(
frequency.valueProperty().asString("%.0f")
);
frequency.valueChangingProperty().addListener((observable, oldValue, newValue) -> {
if (controlButton.isSelected()) {
controlButton.fire();
}
});
// start and stop the input task.
controlButton.selectedProperty().addListener((observable, wasSelected, isSelected) -> {
if (isSelected) {
task = new InputTask(
(int) frequency.getValue(),
box.opacityProperty()
);
Thread inputThread = new Thread(task, "input-task");
inputThread.setDaemon(true);
inputThread.start();
controlButton.setText("Stop");
} else {
if (task != null) {
task.cancel();
}
controlButton.setText("Start");
}
});
// create the layout
VBox layout = new VBox(
10,
frequency,
new HBox(5, new Label("Frequency: " ), frequencyLabel, new Label("Hz"),
controlButton,
box,
new HBox(5, new Label("Brightness: " ), brightness)
);
layout.setPadding(new Insets(10));
// display the scene
stage.setScene(new Scene(layout));
stage.show();
}
// simulates accepting random input from an input feed at a given frequency.
class InputTask extends Task<Void> {
private final DoubleProperty changeableProperty;
private final long sleeptime;
final AtomicLong counter = new AtomicLong(-1);
final Random random = new Random(42);
public InputTask(int inputFrequency, DoubleProperty changeableProperty) {
this.changeableProperty = changeableProperty;
this.sleeptime = (long) ((1.0 / inputFrequency) * 1_000);
}
#Override
protected Void call() throws InterruptedException {
long count = 0 ;
while (!Thread.interrupted()) {
count++;
double newValue = random.nextDouble(); // input simulation
if (counter.getAndSet(count) == -1) {
Platform.runLater(() -> {
changeableProperty.setValue(newValue);
counter.getAndSet(-1);
});
}
Thread.sleep(sleeptime);
}
return null;
}
}
public static void main(String[] args) {
System.out.println(1.0/100*1000);
}
}
Trying to control the display of a message based on the value in a TextField. I have a fade away timed message display based on certain value input in the TextField box. Like to have a mouse hover over to display the same message while the input value is still invalid. Looks like the code I have below would still show the message even after the input value has beed changed to be valid.
...
errorLimit.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable,
String oldValue, String newValue) {
if (newValue.trim().length() > 0) {
int enteredValue = Integer.parseInt(newValue);
if (enteredValue <1 || enteredValue >25000) {
errorLimit.setStyle("-fx-text-fill: red");
Dialogs.flash(errorLimit, "The error limit can not be zero or blank or greater than 25,000");
if (errorLimit.getStyle().equals("-fx-text-fill: red")) {
errorLimit.setOnMouseEntered(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent t) {
Dialogs.flash(errorLimit, "The error limit can not be zero or blank or greater than 25,000");
}
});
}
} else {
errorLimit.setStyle("-fx-text-fill: black");
}
}
}
});
...
Any idea how I can do this? Thanks!
Just put the if(...) clause inside the handle(...) method...
errorLimit.textProperty().addListener(new ChangeListener<String>() {
#Override
public void changed(ObservableValue<? extends String> observable,
String oldValue, String newValue) {
if (newValue.trim().length() > 0) {
int enteredValue = Integer.parseInt(newValue);
if (enteredValue <1 || enteredValue >25000) {
errorLimit.setStyle("-fx-text-fill: red");
Dialogs.flash(errorLimit, "The error limit can not be zero or blank or greater than 25,000");
} else {
errorLimit.setStyle("-fx-text-fill: black");
}
}
}
});
errorLimit.setOnMouseEntered(new EventHandler<MouseEvent>() {
#Override
public void handle(MouseEvent t) {
if (errorLimit.getStyle().equals("-fx-text-fill: red")) {
Dialogs.flash(errorLimit, "The error limit can not be zero or blank or greater than 25,000");
}
}
});
I would strongly suggest creating a BooleanProperty to indicate if the field is valid or not, instead of checking the value of the style; but that's a different issue I guess.
I'm developing an Android game with LibGDX. And I need to find the height of the soft-keyboard the user is using, as I want to display some objects right above the keyboard.
I have read this thread:
how can i get soft keyboard height on android?
But the comment suggests that it doesn't work, and it also seems to be for using with Android SDK. I'm not sure. Does anyone know a way that will definitely work?
If your problem is that your textfields are obscured then I suggest using
void Gdx.input.getTextInput(Input.TextInputListener listener,
java.lang.String title,
java.lang.String text)
instead because that will generate a native modal text input dialog that moves up and down with the keyboard. I have tried to get the height of the keyboard as well but so far I haven't managed.
See answers for this thread as well:
How do libgdx detect keyboard presence
Hopefully someone will find this answer helpful:
There is a workout to detect the exact height of the soft-keyboard which involve the Launcher Activity to send screen dimension to the game when a screen resize event occurs.
First, set a layout listener on the ViewTreeObserver of the rootView of your LauncherActivity:
public class AndroidLauncher extends AndroidApplication {
//...
public void setListenerToRootView() {
final View activityRootView = getWindow().getDecorView().findViewById(android.R.id.content);
activityRootView.getViewTreeObserver().addOnGlobalLayoutListener(keyboardLayoutListener);
}
private ViewTreeObserver.OnGlobalLayoutListener keyboardLayoutListener = new ViewTreeObserver.OnGlobalLayoutListener() {
#Override
public void onGlobalLayout() {
Rect visibleDisplayFrame = new Rect();
getWindow().getDecorView().getWindowVisibleDisplayFrame(visibleDisplayFrame);
game.screenResize(visibleDisplayFrame.width(), visibleDisplayFrame.height());
}
};
//...
}
If you try to get the height of the root view, it will not work as most of the games are fullscreen.
Don't forget to add and remove the listener on appropriate occurrences:
#Override
protected void onCreate (Bundle savedInstanceState) {
//...
setListenerToRootView();
}
#Override
protected void onDestroy () {
super.onDestroy();
removeListenerToRootView();
}
public void removeListenerToRootView() {
final View activityRootView = getWindow().getDecorView().findViewById(android.R.id.content);
activityRootView.getViewTreeObserver().removeOnGlobalLayoutListener(keyboardLayoutListener);
}
Next, declare the screenResize method inside the Game Class which will receive the dimensions and send it to the current screen:
public class YourGame extends Game {
//...
public ScreenBase currentScreen;
//...
public void screenResize(float width, float height) {
if(currentScreen != null)
currentScreen.onScreenResize(width, height);
}
//...
}
Every screen that involves a change must implement the onScreenResize method. Introduce an Abstract Base Class of screen that has an abstract method onScreenResize. The currentScreen variable must be set in the constructor:
public abstract class ScreenBase implements Screen {
//...
public ScreenBase(YourGame game) {
//...
this.game = game;
this.game.currentScreen = this;
//....
}
public abstract void onScreenResize(float width, float height);
Implement these in whichever screen you want:
public class LoginScreen extends ScreenBase {
//...
#Override
public void onScreenResize(final float width, final float height) {
if(Gdx.graphics.getHeight() > height) {
Gdx.app.log("LoginScreen", "Height of keyboard: " + (Gdx.graphics.getHeight() - height));
}
}
}