I coded a simple indicator for NT8. This indicator is supposed to plot a histogram bar when the previous candle is an up candle. It compiles without problem. However, it just doesn't plot anything. After attaching it to the chart, the indicator window shows blank. The code is very simple, the OnBarUpdate() section only consists of one line. How to fix it ? The source code under OnBarUpdate() is as following:

protected override void OnBarUpdate()
{
Value[0]=(Close[1]>Open[1] ? 1:0);
}

The complete source code file is as attached.

Thank you in advance for anyone that can help.

this is a common mistake of first time coder make, you need to wait for the bar data to be there first
In this case you need to wait for bar[1] before the code can be executed successful
thus;

protected override void OnBarUpdate()
{
if (CurrentBar < 1 ) return; // skip if not bar[1] yet


Value[0]=(Close[1]>Open[1] ? 1:0);
}