Indicator zero line?

[fenepet965]

Hi, is there a way to show the zero line in a Simplified API Indicator?

Thanks,

[Andry API support]

Could you pls clarify what is zero line.

[fenepet965]

On the bottom chart of Bookmap... Can I make an indicator that shows or highlights the 0 line while also showing its own values?

[Andry API support]

Here is an example. There is a zero indicator and a last trade indicator. To show indicators on the same axis (otherwise there would be 2 axes - one for each indicator) an axis group is used so indicators are grouped to use 1 axis.
!!! If the purpose of zero line is just to have zero on the bottom chart you can use 1 indicator but set axis rules - see the second example.

Code: Select all

package velox.api.layer1.simplified.demo;

import java.awt.Color;

import velox.api.layer1.annotations.Layer1ApiVersion;
import velox.api.layer1.annotations.Layer1ApiVersionValue;
import velox.api.layer1.annotations.Layer1SimpleAttachable;
import velox.api.layer1.annotations.Layer1StrategyName;
import velox.api.layer1.data.InstrumentInfo;
import velox.api.layer1.data.TradeInfo;
import velox.api.layer1.messages.indicators.Layer1ApiUserMessageModifyIndicator.GraphType;
import velox.api.layer1.simplified.Api;
import velox.api.layer1.simplified.AxisGroup;
import velox.api.layer1.simplified.CustomModule;
import velox.api.layer1.simplified.Indicator;
import velox.api.layer1.simplified.InitialState;
import velox.api.layer1.simplified.TradeDataListener;

@Layer1SimpleAttachable
@Layer1StrategyName("LastTradeBottomZero")
@Layer1ApiVersion(Layer1ApiVersionValue.VERSION2)
public class LastTradeBottomZero implements CustomModule, TradeDataListener
{
    protected Indicator lastTradeIndicator;
    protected Indicator zeroIndicator;
    private AxisGroup group = new AxisGroup();
    InstrumentInfo info;

    @Override
    public void initialize(String alias, InstrumentInfo info, Api api, InitialState initialState) {
        lastTradeIndicator = api.registerIndicator("LastTradeBottomZero", GraphType.BOTTOM);
        lastTradeIndicator.setColor(Color.GREEN);
        zeroIndicator = api.registerIndicator("Zero", GraphType.BOTTOM, 0);
        zeroIndicator.setColor(Color.RED);
        group.add(lastTradeIndicator);
        group.add(zeroIndicator);
        this.info = info;
    }
    
    @Override
    public void stop() {
    }

    @Override
    public void onTrade(double price, int size, TradeInfo tradeInfo) {
        lastTradeIndicator.addPoint(price * info.pips);
    }
}

One indicator + axis rules

Code: Select all

public class LastTradeBottomZeroAxisRules implements CustomModule, TradeDataListener
{
    protected Indicator lastTradeIndicator;
    private AxisGroup group = new AxisGroup();
    InstrumentInfo info;

    @Override
    public void initialize(String alias, InstrumentInfo info, Api api, InitialState initialState) {
        lastTradeIndicator = api.registerIndicator("LastTradeBottomZeroAxisRules", GraphType.BOTTOM);
        lastTradeIndicator.setColor(Color.GREEN);
        group.add(lastTradeIndicator);
        AxisRules rules = new AxisRules();
        rules.setForcedMin(0);
        group.setAxisRules(rules);
        this.info = info;
    }
    
    @Override
    public void stop() {
    }

    @Override
    public void onTrade(double price, int size, TradeInfo tradeInfo) {
        lastTradeIndicator.addPoint(price * info.pips);
    }
}

[Andry API support]

If you wish one indicator to alternate between zero and non-zero values the visible result will depend on how often the values change from zero to non-zero. Due to data aggregation some values may be missed.
In this example (a bad example of alternating) non-zero values exist for a tiny fraction of second. The aggregation will simply hide non-zero values.

Code: Select all

    protected Indicator lastTradeIndicator;
    private AxisGroup group = new AxisGroup();
    InstrumentInfo info;

    @Override
    public void initialize(String alias, InstrumentInfo info, Api api, InitialState initialState) {
        lastTradeIndicator = api.registerIndicator("LastTradeBottomZeroAxisRulesAlternate", GraphType.BOTTOM);
        lastTradeIndicator.setColor(Color.GREEN);
        group.add(lastTradeIndicator);
        AxisRules rules = new AxisRules();
        rules.setForcedMin(0);
        group.setAxisRules(rules);
        this.info = info;
    }
    
    @Override
    public void stop() {
    }

    @Override
    public void onTrade(double price, int size, TradeInfo tradeInfo) {
        lastTradeIndicator.addPoint(price * info.pips);
        lastTradeIndicator.addPoint(0);
    }

To make the example look meaningful you may want to use delays for plotting zero values so non-zero values stay on chart for some time

Code: Select all

@Layer1SimpleAttachable
@Layer1StrategyName("LastTradeBottomZeroAxisRulesAlternate")
@Layer1ApiVersion(Layer1ApiVersionValue.VERSION2)
public class LastTradeBottomZeroAxisRulesAlternate implements CustomModule, TradeDataListener, TimeListener
{
    protected Indicator lastTradeIndicator;
    private AxisGroup group = new AxisGroup();
    InstrumentInfo info;
    ExecutorService executor = Executors.newSingleThreadExecutor();
    long t;
    long lastTradeT;

    @Override
    public void initialize(String alias, InstrumentInfo info, Api api, InitialState initialState) {
        lastTradeIndicator = api.registerIndicator("LastTradeBottomZeroAxisRulesAlternate", GraphType.BOTTOM);
        lastTradeIndicator.setColor(Color.GREEN);
        group.add(lastTradeIndicator);
        AxisRules rules = new AxisRules();
        rules.setForcedMin(0);
        group.setAxisRules(rules);
        this.info = info;
    }
    
    @Override
    public void stop() {
    }

    @Override
    public void onTrade(double price, int size, TradeInfo tradeInfo) {
        executor.execute(() -> {
            lastTradeT = t;
            lastTradeIndicator.addPoint(price * info.pips);
        });
        
        Thread th = new Thread(() -> {
            long storedT = lastTradeT;
            try {
                TimeUnit.SECONDS.sleep(1);
            } catch (InterruptedException e) {
                Log.info("", e);
            }
            if (lastTradeT == storedT) {//if no onTrade events came during the recent second
                executor.execute(() -> {
                    lastTradeIndicator.addPoint(0);
                });
            }
        });
        th.start();
    }

    @Override
    public void onTimestamp(long t) {
        this.t = t;
    }
}

[fenepet965]

Thanks so much Andrey, I really appreciate all the examples