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adding Icons with String to MPAndroid Chart as XAxisValues

github.PhilJay:MPAndroidChart:v2.0.9`
I was wondering if I can add star icons and numbers as XAxisValues like image below?
I've already added the numbers and it's working fine but I don't know how to add star icons! Is there a way to combine text and icons?
Here is my code so far:
private ArrayList<BarDataSet> getDataSet(int stars1, int stars2, int stars3, int stars4, int stars5) {
ArrayList<BarDataSet> dataSets = null;
ArrayList<BarEntry> valueSet1 = new ArrayList<>();
BarEntry v1e1 = new BarEntry(stars5, 4);
valueSet1.add(v1e1);
BarEntry v1e2 = new BarEntry(stars4, 3);
valueSet1.add(v1e2);
BarEntry v1e3 = new BarEntry(stars3, 2);
valueSet1.add(v1e3);
BarEntry v1e4 = new BarEntry(stars2, 1);
valueSet1.add(v1e4);
BarEntry v1e5 = new BarEntry(stars1, 0);
valueSet1.add(v1e5);
BarDataSet barDataSet1 = new BarDataSet(valueSet1, "");
barDataSet1.setColors(new int[]{getResources().getColor(R.color.chart5), getResources().getColor(R.color.chart4),
getResources().getColor(R.color.chart3), getResources().getColor(R.color.chart2), getResources().getColor(R.color.chart1)});
barDataSet1.setValueTextSize(9);
dataSets = new ArrayList<>();
dataSets.add(barDataSet1);
return dataSets;
}
private ArrayList<String> getXAxisValues() {
ArrayList<String> xAxis = new ArrayList<>();
xAxis.add("1");
xAxis.add("2");
xAxis.add("3");
xAxis.add("4");
xAxis.add("5");
return xAxis;
}
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_activity);
BarData data = new BarData(getXAxisValues(), getDataSet(stars1, stars2, stars3, stars4, stars5));
barChart.setData(data);
barChart.setDescription("");
barChart.invalidate();
barChart.getXAxis().setDrawGridLines(false);
barChart.getXAxis().setDrawAxisLine(false);
barChart.setDrawGridBackground(false);
barChart.getAxisLeft().setDrawGridLines(false);
barChart.getAxisRight().setDrawGridLines(false);
barChart.getAxisLeft().setDrawAxisLine(false);
barChart.getAxisRight().setDrawAxisLine(false);
barChart.getLegend().setEnabled(false);
barChart.getXAxis().setDrawLabels(true);
barChart.getXAxis().setPosition(XAxis.XAxisPosition.BOTTOM);
barChart.getAxisRight().setDrawLabels(false);
barChart.getAxisLeft().setDrawLabels(false);
}
Thanks for your time... ♥

Just use ★ character and it will be displayed well. You can use x axis value formatter for formatting values:
barChart.getXAxis().setValueFormatter(new IAxisValueFormatter() {
#Override
public String getFormattedValue(float value, AxisBase axis) {
return "value ★";
}
}
Here is result :

draw a graph using Mpandroid chart

I want to draw a line chart with MPAndroidChart, but when I want to set line data I get this error:
LineData (com.github.mikephil.charting.interfaces.datasets.ILineDataSet...) in LineData cannot be applied to
(java.util.ArrayList, com.github.mikephil.charting.data.LineDataSet)

At present, there is no constructor that accepts List<string>,LineDataSet. The available constructors are:
public LineData() {
super();
}
public LineData(ILineDataSet... dataSets) {
super(dataSets);
}
public LineData(List<ILineDataSet> dataSets) {
super(dataSets);
}
You can read the entire class definition here.
You need to set the x-values differently. This example might help you.

XAxis xAxis = lineChart.getXAxis();
xAxis.setPosition(XAxis.XAxisPosition.BOTTOM);
xAxis.setDrawGridLines(true);
xAxis.setDrawAxisLine(true);
xAxis.setTextSize(10f);
date.clear();
for (int i = 0; i < size; i++) {
date.add("第" + i + "天");
}
//Set the X axis below the data (not the same as the previous version)
xAxis.setValueFormatter(new AxisValueFormatter() {
#Override
public String getFormattedValue(float value, AxisBase axis) {
axis.setGranularityEnabled(true);
axis.resetAxisMaxValue();
axis.isAxisMaxCustom();
int a = (int) value;
return date.get(a);// Data below
}
#Override
public int getDecimalDigits() {
return 0;
}
});
Maybe it will help you

JavaFX ListView very slow

I'm making a chat application using JavaFX for the GUI. I display the chat content in a ListView, but I have one big problem - it's very very slow. When I add new items to the list and especially when I scroll the list up/down. I think maybe it has something to do with the fact that the list refreshes itsellf every time a new item is added (each cell in the list!) and also refreshes every time I scroll up/down.
Does someone know what can I do to solve this problem? TNX
I override ListCell's updateItem:
chatListView.setCellFactory(new Callback<ListView<UserInfo>, ListCell<UserInfo>>() {
#Override
public ListCell<UserInfo> call(ListView<UserInfo> p) {
ListCell<UserInfo> cell = new ListCell<UserInfo>() {
#Override
protected void updateItem(UserInfo item, boolean bln) {
super.updateItem(item, bln);
if (item != null) {
BorderPane borderPane = new BorderPane();
ImageView profileImage = new ImageView(new Image(item.getImageURL()));
profileImage.setFitHeight(32);
profileImage.setFitWidth(32);
Rectangle clip = new Rectangle(
profileImage.getFitWidth(), profileImage.getFitHeight()
);
clip.setArcWidth(30);
clip.setArcHeight(30);
profileImage.setClip(clip);
SnapshotParameters parameters = new SnapshotParameters();
parameters.setFill(Color.TRANSPARENT);
WritableImage image = profileImage.snapshot(parameters, null);
profileImage.setClip(null);
profileImage.setImage(image);
ImageView arrowImage = new ImageView(new Image("arrow1.png"));
ImageView arrowImage2 = new ImageView(new Image("arrow1.png"));
Label nameLabel = new Label(item.getUserName());
nameLabel.setStyle(" -fx-text-alignment: center; -fx-padding: 2;");
HBox hbox = null;
Label textLabel = new Label();
String messageText = splitTolines(item.getMessage());
textLabel.setText(messageText);
textLabel.setStyle("-fx-background-color: #a1f2cd; "
+ "-fx-padding: 10;\n"
+ "-fx-spacing: 5;");
hbox = new HBox(arrowImage, textLabel);
VBox vbox = new VBox(profileImage, nameLabel);
BorderPane.setMargin(vbox, new Insets(0, 10, 10, 10));
BorderPane.setMargin(hbox, new Insets(10, 0, 0, 0));
//Time
Date dNow = new Date();
SimpleDateFormat ft = new SimpleDateFormat("hh:mm a");
Label timeLabel = new Label(ft.format(dNow));
timeLabel.setStyle("-fx-font: 8px Tahoma; -fx-width: 100%");
HBox hbox2 = new HBox(arrowImage2, timeLabel);
arrowImage2.setVisible(false);
VBox vbox2 = new VBox(hbox, hbox2);
borderPane.setCenter(vbox2);
borderPane.setLeft(vbox);
setGraphic(borderPane);
}
}
};
return cell;
}
});

Never ever add (big) GUI Elements in updateItem() without checking if it is not already there.
updateItem() is called everytime for EVERY SINGLE ROW when you scroll, resize or change gui in any other way.
You should alway reset the graphic to null if you do not have an item or the second boolean of updateItem(item, empty) is false, because the second boolean is the EMPTY flag.
I recommend to you that you use a VBox instead of a ListView.

You must not build new instances of your components everytime the view gets updated.
Instanciate them one time initialy, then you reuse and change their attributes.

I just noticed that too. It's too slow even for a list containing only 5-10 items (with scaled images and text). Since I need no selection feature, I also rewrote the code to use VBox instead and the slowness is immediately gone!
To emulate the setItems, I have a helper function which you may find handy:
public static <S, T> void mapByValue(
ObservableList<S> sourceList,
ObservableList<T> targetList,
Function<S, T> mapper)
{
Objects.requireNonNull(sourceList);
Objects.requireNonNull(targetList);
Objects.requireNonNull(mapper);
targetList.clear();
Map<S, T> sourceToTargetMap = new HashMap<>();
// Populate targetList by sourceList and mapper
for (S s : sourceList)
{
T t = mapper.apply(s);
targetList.add(t);
sourceToTargetMap.put(s, t);
}
// Listen to changes in sourceList and update targetList accordingly
ListChangeListener<S> sourceListener = new ListChangeListener<S>()
{
#Override
public void onChanged(ListChangeListener.Change<? extends S> c)
{
while (c.next())
{
if (c.wasPermutated())
{
for (int i = c.getFrom(); i < c.getTo(); i++)
{
int j = c.getPermutation(i);
S s = sourceList.get(j);
T t = sourceToTargetMap.get2(s);
targetList.set(i, t);
}
}
else
{
for (S s : c.getRemoved())
{
T t = sourceToTargetMap.get2(s);
targetList.remove2(t);
sourceToTargetMap.remove2(s);
}
int i = c.getFrom();
for (S s : c.getAddedSubList())
{
T t = mapper.apply(s);
targetList.add(i, t);
sourceToTargetMap.put(s, t);
i += 1;
}
}
}
}
};
sourceList.addListener(new WeakListChangeListener<>(sourceListener));
// Store the listener in targetList to prevent GC
// The listener should be active as long as targetList exists
targetList.addListener((InvalidationListener) iv ->
{
Object[] refs = { sourceListener, };
Objects.requireNonNull(refs);
});
}
It can then be used like:
ObservableList<Bookmark> bookmarkList;
VBox bookmarkListVBox;
mapByValue(bookmarkList, bookmarkListVBox.getChildren(), bmk -> new Label(bmk.getName());
To automatically update the list (VBox's children) from observable list.
PS: other functions such as grouping are here => ObservableListHelper

Java FX - BarChart dynamically added content destroys the layout

I'm struggeling with the Java FX BarChart.. My own implementation of the chart is a class that extends the Java FX GridPane and holds a BarChart as a member variable.
If I initialize the whole thing everything works perfect, but if I change the data dynamically (add one or remove one data) the layout will be destroyed.
Speaking in pictures this means: (sorry i can't upload picture at the moment)
pic1 - initialization
after adding one element
So the 1st pictures shows the chart after initalization, the 2nd after one element has been added and after deleting one element the categories aren't shown anymore. (I Ccan't upload a picture of this)
So here's my code:
import javafx.collections.FXCollections;
import javafx.collections.ObservableList;
import javafx.scene.chart.BarChart;
import javafx.scene.chart.CategoryAxis;
import javafx.scene.chart.NumberAxis;
import javafx.scene.chart.XYChart.Data;
import javafx.scene.chart.XYChart.Series;
import javafx.scene.control.Tooltip;
import javafx.scene.layout.GridPane;
import javafx.scene.layout.Priority;
import someCompanyThings.IMyBarChart;
import someCompanyThings.LocaleService;
import someCompanyThings.INlsKey;
/**
* A Chart with vertical or horizontal bars. It is assumed that the Bars represent positive integer numbers.
* Data may be added or removed dynamically but on the first intent it should display static.
*/
public class MyBarChart extends GridPane implements IMyBarChart {
/*
* Due to data binding problems with a generic bar chart, we hold the two possible bar charts as member variables.
* Also each of them get's a list of Series<?, ?>
*/
private BarChart<String, Number> _barChartVertical;
private BarChart<Number, String> _barChartHorizontal;
private final ObservableList<Series<String, Number>> _dataVertical = FXCollections.observableArrayList();
private final ObservableList<Series<Number, String>> _dataHorizontal = FXCollections.observableArrayList();
private long _maxValue = 0;
private boolean _numberAxisInPercent = false;
private boolean _horizontal = false;
public MyBarChart(INlsKey pTitle, INlsKey pXLabel, INlsKey pYLabel, boolean pNumberAxisInPercent, boolean pHorizontal) {
super();
CategoryAxis categoryAxis = new CategoryAxis();
categoryAxis.setId("bar-chart-category-axis");
NumberAxis numberAxis = new NumberAxis(0.0, 1.0, 1.0);
numberAxis.setId("bar-chart-number-axis");
// create bar chart
// horizontal means that the x-axis is a number axis and the y-axis is a category axis
if (pHorizontal) {
categoryAxis.setLabel(LocaleService.getMessage(pYLabel));
numberAxis.setLabel(LocaleService.getMessage(pXLabel));
_barChartHorizontal = new BarChart<Number, String>(numberAxis, categoryAxis);
_barChartHorizontal.setData(_dataHorizontal);
_barChartHorizontal.setTitle(LocaleService.getMessage(pTitle));
getChildren().add(_barChartHorizontal);
}
else {
categoryAxis.setLabel(LocaleService.getMessage(pXLabel));
numberAxis.setLabel(LocaleService.getMessage(pYLabel));
_barChartVertical = new BarChart<String, Number>(categoryAxis, numberAxis);
_barChartVertical.setData(_dataVertical);
_barChartVertical.setTitle(LocaleService.getMessage(pTitle));
getChildren().add(_barChartVertical);
}
_numberAxisInPercent = pNumberAxisInPercent;
_horizontal = pHorizontal;
/*
* layout
*/
setHgrow(getChildren().get(0), Priority.ALWAYS);
setVgrow(getChildren().get(0), Priority.ALWAYS);
}
#Override
public IMyBarChart addSeries(INlsKey pSeriesName, ObservableList<Data<String, Number>> pDataSet) {
final Series<String, Number> series = new Series<String, Number>(LocaleService.getMessage(pSeriesName), pDataSet);
_dataVertical.add(series);
// iterate over the whole data segment and add it to the series
for (final Data<String, Number> data : pDataSet) {
Tooltip tooltip = new Tooltip();
tooltip.setText(data.getXValue());
Tooltip.install(data.getNode(), tooltip);
if (data.getYValue().longValue() > _maxValue) {
_maxValue = data.getYValue().longValue();
}
}
setNumberAxisScale();
return this;
}
#Override
public IMyBarChart addSeriesHorizontal(INlsKey pSeriesName, ObservableList<Data<Number, String>> pDataSet) {
final Series<Number, String> series = new Series<Number, String>(LocaleService.getMessage(pSeriesName), pDataSet);
_dataHorizontal.add(series);
// iterate over the whole data segment and add it to the series
for (final Data<Number, String> data : pDataSet) {
Tooltip tooltip = new Tooltip();
tooltip.setText(data.getYValue());
Tooltip.install(data.getNode(), tooltip);
if (data.getXValue().longValue() > _maxValue) {
_maxValue = data.getXValue().longValue();
}
}
setNumberAxisScale();
return this;
}
private void setNumberAxisScale() {
NumberAxis numberAxis = getNumberAxis();
// set the number axis as a percent axis
if (_numberAxisInPercent) {
numberAxis.setUpperBound(100);
numberAxis.setTickUnit(10);
}
else {
numberAxis.setUpperBound(_maxValue + 1);
numberAxis.setTickUnit(1);
}
}
#Override
public void setLegendVisible(boolean pVisible) {
if (_barChartHorizontal != null) {
_barChartHorizontal.setLegendVisible(pVisible);
}
else {
_barChartVertical.setLegendVisible(pVisible);
}
}
#Override
public void setCategories(ObservableList<String> pCategories) {
getCategoryAxis().getCategories().setAll(pCategories);
}
/**
*
* #return the category axis of the used bar chart
*/
private CategoryAxis getCategoryAxis() {
if (_horizontal) {
return (CategoryAxis)_barChartHorizontal.getYAxis();
}
else {
return (CategoryAxis)_barChartVertical.getXAxis();
}
}
/**
*
* #return the number axis of the used bar chart
*/
private NumberAxis getNumberAxis() {
if (_horizontal) {
return (NumberAxis)_barChartHorizontal.getXAxis();
}
else {
return (NumberAxis)_barChartVertical.getYAxis();
}
}
}
The initialization process:
final IMyBarChart tablespacesChart = MyFactory.createBarChart(NlsKeys.tablespacesTitle, NlsKeys.tablespacesXAxis,
NlsKeys.tablespacesYAxis, true, true);
// first bool -> numberAxisInPercent, second bool -> horizontal ortientation
tablespacesChart.setLegendVisible(false);
tablespacesChart.setCategories(model.getListCategories());
tablespacesChart.addSeriesHorizontal(NlsKeys.tablespacesLegendYAxis, model.getListDataUsedMax());
The data changes are realised by another class that just uses
model.getCategories().setAll(MyNewCatList); // or
model.getListDataUsedMax().setAll(MyNewList);
Well, i also tried to implement the chart with just one member variable (like BarChart _barChart) but this didn't work.
Now i have those layout issues and i dunno where they come from. So i hope you can give me a hint :-)

Here's my solution:
First, create a subclass of bar chart to access the private method updateAxisRange:
class MyBarChart<X, Y> extends BarChart<X, Y> {
public MyBarChart(Axis xAxis, Axis yAxis) {
super(xAxis, yAxis);
}
public void relayout() {
updateAxisRange();
}
}
Next, instantiate your bar chart as MyBarChart:
MyBarChart<String, Number> barChart = new MyBarChart<String, Number>(xAxis, yAxis);
And Lastly, you need to listen to resize events on the parent containing the chart, and when they occur, invoke the relayout of the chart.
For example:
BorderPane pane = new BorderPane(barChart);
pane.widthProperty().addListener(new ChangeListener<Number>() {
#Override
public void changed(ObservableValue<? extends Number> arg0, Number arg1, Number arg2) {
barChart.relayout();
}
});

How to change color of a single bar java fx

Here is my code which generates bar chart of 10 values from 0 to 10 . i want to change the color of bars as follows
if i>5 color==red
if i>8 color==blue
so the final out will be 0-5(default yellow bars) 6-8(Red bars) 9(blue bar)
kindly help me..
thanks
public class BarChartSample extends Application {
#Override
public void start(Stage stage) {
stage.setTitle("Bar Chart Sample");
final CategoryAxis xAxis = new CategoryAxis();
final NumberAxis yAxis = new NumberAxis();
final BarChart < String, Number > bc = new BarChart < String, Number > (xAxis, yAxis);
bc.setTitle("Country Summary");
xAxis.setLabel("bars");
yAxis.setLabel("Value");
XYChart.Series series1 = new XYChart.Series();
series1.setName("...");
for (int i = 0; i < 10; i++) {
//here i want to change color of bar if value of i is >5 than red if i>8 than blue
series1.getData().add(new XYChart.Data("Value", i));
}
}
public static void main(String[] args) {
launch(args);
}
}

I created a sample solution.
The solution works by setting the bar's -fx-bar-fill color to a different color based on the value of the bar's data.
final XYChart.Data<String, Number> data = new XYChart.Data("Value " + i , i);
data.nodeProperty().addListener(new ChangeListener<Node>() {
#Override public void changed(ObservableValue<? extends Node> ov, Node oldNode, Node newNode) {
if (newNode != null) {
if (data.getYValue().intValue() > 8 ) {
newNode.setStyle("-fx-bar-fill: navy;");
} else if (data.getYValue().intValue() > 5 ) {
newNode.setStyle("-fx-bar-fill: firebrick;");
}
}
}
});