Custom TextBlock OnPriceChange

[lunardiplomacy]

Hello community,

I have created a custom TextBlock which displays my calculated value in the specified area of the chart using a grid which is created during dispatcher.invokeasync and the textblock is added.

This all works great, and I know it's a C# docs matter anyway, however the content of my textblock in the way I have it implemented is static and I need the text to update OnPriceChange. Can somebody help me with this? I tried a few solutions, one of which created catastrophe and came very close to reinstall as my only option, so now I am turning for help.

Please let me know if you need any additional information, and as I side note I would like to ask if there is a simpler way to add text to a chart coordinate. Like Draw.TextFixed but with my freedom as to where I can place the fixed text. I want it top center and that isn't an option. Thank you!

[NinjaTrader_Jesse]

Hello lunardiplomacy,

You can likely avoid a TextBlock or WPF elements for this purpose and just use OnRender to draw fixed text. The Draw.TextFixed has specific placements, you could instead use the SampleCustomRender indicator and how it draws text for any placement on the chart panel.

If you do want to use a WPF control here I would need more details on what went wrong. It sounds like you had the right approach, if you are updating the value you would also need to invoke that on the UI thread, potentially that is what you were missing.

I look forward to being of further assistance.

[lunardiplomacy]

Thanks for the response, Jesse.

I will look into sampleCustomRender, for this particular purpose it sounds like it would probably be sufficient.

But yes, it was in trying to invoke on the UI thread that things started to go terribly wrong. I didn't know where I should attach the code, so I attached it to a mouse move event without realizing the fairly obvious consequences of that. Where should I be updating the content? OnBarUpdate? in that case I got a lot of object instance errors.

Thanks, Jesse.

[NinjaTrader_Jesse]

Hello lunardiplomacy,

Yes the mouse move wouldn't be suggested, OnBarUpdate would be sufficient if that is the rate you wanted it to update. For example if the calculation is in OBU then that logic could go at the end of OBU.

If you had object reference errors that likely relates to what you coded and where variables were used or when they are populated. Checking for null is a common C# topic which comes up frequently, in NinjaScript you can also need this in some cases. That is simply doing a condition like:

if(x != null)
{
    x is valid here. x is your object reference or whatever object threw the error
}

If you have a small sample you can always upload those with your post as an attachment. The .cs file would be fine for that.

I look forward to being of further assistance.