Develop Reference

Creating a spinning pie chart (wheel) android

I have created an Pie chart which I want to spin randomly and stop on click.
Then my android program needs to read which value is above.
I already got this:
PieDataSet dataSet = new PieDataSet(yvalues, "");
ArrayList<String> xVals = new ArrayList<String>();
ArrayList<Integer> colors = new ArrayList<Integer>();
pieChart.setDrawHoleEnabled(false);
pieChart.animateXY(1400, 1400);
pieChart.getLegend().setEnabled(false);
pieChart.setDrawSliceText(false);
dataSet.setDrawValues(false);
xVals.add("Correct");
xVals.add("Wrong");
colors.add(Color.rgb(115, 255, 134));
colors.add(Color.rgb(255, 115, 115));
dataSet.setColors(colors);
pieChart.setDescription("");
PieData data = new PieData(xVals, dataSet);
data.setValueFormatter(new PercentFormatter());
data.setValueTextSize(18f);
data.setValueTextColor(Color.BLACK);
pieChart.setData(data);
pieChart.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
pieChart.spin( 500,0,-360f, Easing.EasingOption.EaseInOutQuad);
}
});
I don't know how to spin this chart on click and stop it randomly.
Then I need to get the value of the chart which is spinned.

You can use this library.
(Easy and simple implementation of PieChart with Scatter)
This library will fulfill all the requirements you have mentioned above.
https://android-arsenal.com/details/1/4492

How to add real time data in Barchart using MPAndroidChart library

I am using MPAndroid Chart library to draw BarChart.
But not getting how to draw bars with real time data in on button click.
Can anyone please help me in this.
Thanks.

After getting data store that in List(graphData). Then,
BarChart barChart;
/*List to store real time data*/
private List<Integer> graphData = new ArrayList<>();
/*List of String which contains X-axis values */
ArrayList<String> xAxisValuesList = new ArrayList<>();
// create BarEntry for group
ArrayList<BarEntry> group = new ArrayList<>();
for (int i = 0; i < graphData.size(); i++) {
Log.d(TAG, "generating for:" + graphData.get(i));
group.add(new BarEntry(graphData.get(i), i));
}
// creating dataset for group
BarDataSet barDataSet = new BarDataSet(group, "Label");
// combined all dataset into an arraylist
ArrayList<BarDataSet> dataSets = new ArrayList<>();
dataSets.add(barDataSet);
// initialize the Bardata with argument labels and dataSet
BarData barData = new BarData(xAxisValuesList, dataSets);
barChart.setData(barData);

I am trying to make values of X axis show on the bottom of the graph not the top, using MP android chart

I created a graph app using MP android chart, i used it to plot two different line data sets . But my problem is that the value labels for the xaxis appear on the top of the graph . I need a way to make it to the bottom . below is my code
final LineChart linechart = (LineChart)findViewById(R.id.idlinechart);
//created list enties to hold the values
List<Entry> valuesCompany1 = new ArrayList<>(); List<Entry> valuesCompany2 = new ArrayList<>();
//created entry values to be entered into the lsit entry b
Entry c1e1 = new Entry(0f, 100000f); valuesCompany1.add(c1e1);
Entry c1e2 = new Entry (1f, 140000f);valuesCompany1.add(c1e2);
Entry c1e3 = new Entry(2f,90000f);valuesCompany1.add(c1e3);
Entry c1e4 = new Entry (3f, 150000f); valuesCompany1.add(c1e4);
Entry c2e1 = new Entry(0f, 50000f); valuesCompany2.add(c2e1);
Entry c2e2 = new Entry (1f, 50000f);valuesCompany2.add(c2e2);
Entry c2e3 = new Entry(2f,150000f);valuesCompany2.add(c2e3);
Entry c2e4 = new Entry (3f, 110000f); valuesCompany2.add(c2e4);
//so now we create line data to hold the list
LineDataSet linedatasetComp1 = new LineDataSet(valuesCompany1, "company 1");
linedatasetComp1.setAxisDependency(YAxis.AxisDependency.LEFT);
linedatasetComp1.setColor(Color.BLUE);
LineDataSet linedatasetComp2 = new LineDataSet(valuesCompany2, "company 2");
linedatasetComp2.setAxisDependency(YAxis.AxisDependency.LEFT);
linedatasetComp2.setColor(Color.RED);
List<ILineDataSet> iLinedata = new ArrayList<ILineDataSet>();
iLinedata.add(linedatasetComp1); //adding the line data sets into the line data list
iLinedata.add(linedatasetComp2);
//setting the Ilinedata list into line data
LineData linedata = new LineData(iLinedata);
//setting the line data into line chart
linechart.setData(linedata);
linechart.invalidate(); //refreshing the line chart
//Saving the picture to galery
Button savebutton = (Button)findViewById(R.id.button);
savebutton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
linechart.saveToGallery("new Line chart", 150);
Toast.makeText(getApplicationContext(), "graph saved ", Toast.LENGTH_LONG).show();
}
});
final String[] Quaters = {"Q1", "Q2", "Q3", "Q4"};
IAxisValueFormatter valueFormater = new IAxisValueFormatter() {
#Override
public String getFormattedValue(float value, AxisBase axis) {
return Quaters[(int) value];
}
#Override
public int getDecimalDigits() {
return 0;
}
};
XAxis xAxis = linechart.getXAxis();
xAxis.setGranularity(1f);
xAxis.setValueFormatter(valueFormater);
Description desc = new Description();
desc.setText("A graph comparing revenuews of two companies ");
desc.setEnabled(true);
desc.setPosition(0,0);
desc.setTextColor(Color.BLACK);
linechart.setDescription(desc);

I don't know if LineChart has that option, but in case it does you just have to get the XAxis adjust the Position like this:
linechart.getXAxis().setPosition(XAxis.XAxisPosition.BOTTOM);
Hope it helps!

Use MPAndroid chart version 2.2.4 or above and use the code
mChart.getXAxis().setPosition(XAxis.XAxisPosition.BOTTOM);
as said by Ponchotg

how to show data by pieces in BarChart Android

I have a problem with BarChart.. I have a 7 item on list. For example
final int[] a = {5,2,10,4,7,8,13};
final String[] b= {"January","February","March","April","May","June","Jully"};
So I want to show by pieces on Barchart. For example first 5 items show and when I click the button than 2 items remaining show in Barchart. Images is,
Than I want when I click the "WAFAW" button barchart is,
But my code working is,
So it means dont show the bar..How can I do that? Thanks for now..
My Code is,
final BarChart barChart = (BarChart) findViewById(R.id.chart);
Button button = (Button) findViewById(R.id.button);
final int[] a = {5,2,10,4,7,8,13};
final String[] b= {"January","February","March","April","May","June","Jully"};
final ArrayList<BarEntry> entries = new ArrayList<>();
final ArrayList<String> labels = new ArrayList<String>();
for(int i=0 ; i<5;i++){
entries.add(new BarEntry(a[i],i));
labels.add(b[i]);
}
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
entries.clear();
labels.clear();
for(int i=5; i<a.length;i++){
entries.add(new BarEntry(a[i],i));
labels.add(b[i]);
}
BarDataSet dataset = new BarDataSet(entries, "# of Calls");
barChart.getXAxis().setPosition(XAxis.XAxisPosition.TOP);
BarData data = new BarData(labels, dataset);
dataset.setColors(ColorTemplate.COLORFUL_COLORS);
barChart.setData(data);
barChart.animateY(3000);
}
});
BarDataSet dataset = new BarDataSet(entries, "# of Calls");
barChart.getXAxis().setPosition(XAxis.XAxisPosition.TOP);
BarData data = new BarData(labels, dataset);
dataset.setColors(ColorTemplate.COLORFUL_COLORS);
barChart.setData(data);
barChart.animateY(3000);

As far as I know there is no simple solution on how to select which bars to display. It depends on how dynamically you want/need to solve it.
The best solution I can think of would be keeing an array of bars to show like:
final int[] show_arr = {0,1,2,3,4,5};
and when onClick() is called you change the array to
final int[] show_arr = {5,7};
and then you run through the whole plotting routine again.
But you add the entries with looping through show_arr
I know this is not a super nice solution, but at least you only have to code the vector hard and can reuse all the other parts.

You can use below code for the same :
https://github.com/blackfizz/EazeGraph
https://github.com/HackPlan/AndroidCharts

How to convert String to Bar entry for MPCharts in android

In my android application, I am new to graphs and using MPchart library to draw the graphs. I'm displaying the graph using string array on both - X axis and Y axis.
For x axis I created it successfully but for Y axis I need to convert my ArrayList<String> to BarData array list. I don't know how to do convert it. Can anyone tell me how to achieve this?
For X axis:
private ArrayList<String> getXAxis() {
ArrayList<String> xAxis = new ArrayList<>();
xAxis = new ArrayList<String>(Arrays.asList(bar_graph_names)); //converting string to arraylist
return xAxis;
}
For Y axis plotting values:
private ArrayList<BarDataSet> getData() {
ArrayList<String> yAxis_conv = new ArrayList<>();
yAxis_conv = new ArrayList<String>(Arrays.asList(bar_graph_values));
ArrayList<BarDataSet> yAxis_Datasets=null;
ArrayList<BarEntry> yAxis = new ArrayList<>();
for(int i = 0; i < bar_graph_values.length; i++)
{
BarEntry [] barentry = new BarEntry[bar_graph_values.length];
barentry[i] = new BarEntry(Float.valueOf(yAxis_conv.get(i)),i);
}
BarDataSet barDataSet1 = new BarDataSet(yAxis_conv , "");//Error occurring line
barDataSet1.setColors(ColorTemplate.COLORFUL_COLORS);
yAxis_Datasets = new ArrayList<>();
yAxis_Datasets.add(barDataSet1);
return yAxis_Datasets;
}

BarData object (which you give to the chart View) consist of one List representing x-values and one or more BarDataSet objects representing y-values data. BarDataSet object has String name and List of y-values.
Your structure of this objects is simply wrong. (for starters yAxis_conv is List<String>, where BarDataSet requires List<BarEntry>). There's more mistakes, but i'm not gonna point them out, just have some working code below:
private void setData() {
ArrayList<String> xVals = new ArrayList<String>();
ArrayList<BarEntry> yVals = new ArrayList<BarEntry>();
xVals = new ArrayList<String>(Arrays.asList(bar_graph_names));
for(int i=0; i < bar_graph_values.length; i++) {
BarEntry entry = new BarEntry(Float.valueOf(bar_graph_values[i]), i);
yVals.add(entry);
}
BarDataSet newSet = new BarDataSet(yVals, "DataSet");
BarData data = new BarData(xVals, newSet);
mChart.setData(data);
}