Win a copy of Think Java: How to Think Like a Computer Scientist this week in the Java in General forum!
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic

GWT Viz API application using server data to render charts

 
Ankit Khujneri
Greenhorn
Posts: 1
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi,

Is there any way to fetch server side data and render it to the
charting components in a GWT-VIZ API enabled app? I tried something
unsure from my side but it did not worked for me.
Scenario: Display some server data on a column chart.
This is what I tried :
<code>
public class ChartPOC implements EntryPoint{


public ArrayList<PaymentObject> plciObj = new
ArrayList<PaymentObject>();
public ColumnChart columnChart ;
public DataTable data ;


public void onModuleLoad() {
Runnable onLoadCallback = new Runnable() {
public void run() { // this is my debug point


ColumnChart.Options options = ColumnChart.Options.create();
ColumnChart tempColumnChart = new ColumnChart(createColTable(),
createColumnOptions(options)); // this creates a column chart
columnChart = tempColumnChart;// set it to the class level chart
// Set up the callback object.
}
};
// Load the visualization api, passing the onLoadCallback to be
called
// when loading is done.
VisualizationUtils.loadVisualizationApi(onLoadCallback,
ColumnChart.PACKAGE);
RootPanel rp = RootPanel.get("sampleCharting");
//rp.add(new HTML("hello"));
rp.add(tempColumnChart);


}


private ColumnChart.Options createColumnOptions(ColumnChart.Options
options) {
//ColumnChart.Options options = ColumnChart.Options.create();
options.setWidth(600);
options.setHeight(400);
options.setColors("#F778A1", "#D16587");
options.setTitle("Earning Analysis");
options.setLegend(LegendPosition.BOTTOM);
options.setShowCategories(true);
options.setTitleX("PLCI");
options.setTitleY("Amount");
options.setTitle("COLUMN CHART WIDGET");
return options;
}


private AbstractDataTable createColTable() {
PLCIServiceAsync service = GWT.create(PLCIService.class);// This is
an Async interface
data = DataTable.create();
data.addColumn(ColumnType.STRING, "PLCI");
data.addColumn(ColumnType.NUMBER, "Payment");
// data.addColumn(ColumnType.NUMBER, "PLCI");
data.addRows(3);


AsyncCallback<ArrayList<PaymentPLCIObject>> callback = new
AsyncCallback<ArrayList<PaymentPLCIObject>>() {// implement
AsyncCallback methods
public void onFailure(Throwable caught) {
// TODO: Do something with errors.
}


public void onSuccess(ArrayList<PaymentPLCIObject> result) {
updateTable(result);// update the DataTable with server
response
}
};
service.getPLCIs(callback);// call the server side service
class's method
return data;
}


private void updateTable(ArrayList<PaymentPLCIObject> result){
for(int index=0; index<result.size(); index++){
PaymentPLCIObject obj = (PaymentPLCIObject)result.get(index);
data.setValue(index, 0,obj.getPlciCode());
data.setValue(index, 1, obj.getPayment());
columnChart.draw(data);
}
}



}


</code>

when I try to debug the app, the app fails when reaches "public void
run() {".
Any help would be appreciated


Thanks
Ankit


 
  • Post Reply
  • Bookmark Topic Watch Topic
  • New Topic