Dukascopy Support Board • View topic - How to add new feed and reload the chart?

MaxR

Hi

It's possible to reload a chart window after change the feed data?

For example:

public class MyStrategy implements IStrategy, IFeedListener {
    //...
    @Override
    public void onStart(IContext context) throws JFException {

        this.chart = context.getLastActiveChart();

        // Create a new feed
        this.chartFeed = new TimePeriodAggregationFeedDescriptor(this.instrument, Period.TWENTY_SECS, this.chartFeed.getOfferSide());
        context.subscribeToFeed(this.chartFeed, this);
        
        // Try to apply new feed to active chart
        //this.chart.setFeedDescriptor(this.chartFeed); // this doesn't work because that method is not exists
        this.chart.repaint();
    }
    //...
}

CriticalSection

Quote:

// Try to apply new feed to active chart
//this.chart.setFeedDescriptor(this.chartFeed); // this doesn't work because that method is not exists
this.chart.repaint();

Addressing the comments above and how to achieve that functionality,
consult the reference Interface IFeedDescriptor then consider the following:

this.chart.getFeedDescriptor().setInstrument(this.chartFeed.getInstrument());
this.chart.getFeedDescriptor().setPeriod(this.chartFeed.getPeriod());
this.chart.getFeedDescriptor().setOfferSide(this.chartFeed.getOfferSide());

MaxR

CriticalSection wrote:

this.chart.getFeedDescriptor().setInstrument(this.chartFeed.getInstrument());
this.chart.getFeedDescriptor().setPeriod(this.chartFeed.getPeriod());
this.chart.getFeedDescriptor().setOfferSide(this.chartFeed.getOfferSide());

Thank's for Your answer. I modify the code:

public class MyStrategy implements IStrategy, IFeedListener {
    //...
    @Override
    public void onStart(IContext context) throws JFException {
 
        this.chart = context.getLastActiveChart();
 
        // Create a new feed
        //this.chartFeed = new TimePeriodAggregationFeedDescriptor(this.instrument, Period.TWENTY_SECS, this.chartFeed.getOfferSide()); // removed - it is unnecessary now
        //context.subscribeToFeed(this.chartFeed, this); // removed - it is unnecessary now
        
        // Change a feed period in active chart
        this.chart.getFeedDescriptor().setPeriod(Period.TWENTY_SECS); //new line
        this.chart.repaint();
    }
    //...
}

And now I have a another problem - the chart isn't refreshed/repainted after period was changed (I test it only in the strategy tester, in visual mode because Today the market is closed;) ).
How can I do it (repaint the chart)?

API Support

MaxR wrote:

It's possible to reload a chart window after change the feed data?

What do you mean by reload? When you manually change the feed then the platform reloads the chart itself. If you do it from SDK, it is done by the SDK. There is no need to handle this yourself.

CriticalSection wrote:

Addressing the comments above and how to achieve that functionality,
consult the reference Interface IFeedDescriptor then consider the following:

this.chart.getFeedDescriptor().setInstrument(this.chartFeed.getInstrument());
this.chart.getFeedDescriptor().setPeriod(this.chartFeed.getPeriod());
this.chart.getFeedDescriptor().setOfferSide(this.chartFeed.getOfferSide());

There is no such functionality as changing the chart's feed from a strategy, however, you can do it programmatically from an SDK program:
https://www.dukascopy.com/wiki/#JForex_SDK/Open_a_chart_from_IClient
and also for back-testing:
https://www.dukascopy.com/wiki/#JForex_SDK/Change_chart_type