Asking about Marquee Text on App Inventor

[Dea Avega Editya]

Hi everyone, i am working on my own app and in the middle of designing the main menu of the app. 

I want to add marquee text on the main menu, i use the simplest path shown in the forum (https://groups.google.com/forum/m/#!topic/app-inventor-instructors/wx_iGTH3m0E) using label as output for marquee text (by abraham getzler), but unfortunately i got this error message just like shown on this picture.

 

I use this blocks above, exatcly the same as the guidance. The components i used are label and clock.

Could you tell me guys what's the problem?

[Scott Ferguson]

In your last block you probably should be using the Source length (95) not the Maximum_length which is why you are getting the error.

Your text is not that long so the segment block fails.

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sf

[Dea Avega Editya]

Hi Scott, thanks for your reply. I followed your suggestion but i got new error message said: Bad Arguments to segment/ The operation segment cant accept the arguments

I used these blocks below:

[Abraham Getzler]

My marquee example was insufficiently bulletproof.

To correct it, use min(length(Feed),maximum_length) as the 

segment length in the assignment to the output label.

Without the min(), the segment() call can be abused with out-of-bounds parameters.

See attached for amended blocks.

Thanks to all who pointed this out.

ABG

[Dea Avega Editya]

Alhamdulillah praise to God! my marquee text works perfectly now. 

Thanks for your clear suggestion Abraham. It's really nice to have you guys here.

Regards from Indonesia