incomprehensible formula for the calculation of a field width.

[forstera]

Hello all,

I installed the application Milestones and for a reason I'm trying to understand, the content of some fields is not displayed because the width calculation seems to give wrong results.

So I broke this calculation down into several parts and there is this that I don't understand at all:

Sum(
    AddColumns(
               Split(
                     Self.Text;
                      ""
                     );
                "Size";
                LookUp(
                       colCharsWidth;
                       CharFont = Self.Font && CharWeight = Self.FontWeight && Char = Result
                       ).Size
               );
      Size
     ) * Self.Size + Self.PaddingLeft + Self.PaddingRight + 2;

According to the code,  I should receive here a sume value of differents elements : The addition  of an 'Addcolumns function and  a Size. Here, I dont understand what is this 'Size' because it's related to nothing and it doesent' seen it's a variable.

Then the AddColumns function :

According to the documentation, it should be like this : AddColumns( Table, ColumnName1, Formula1 [, ColumnName2, Formula2, ... ] )

but here, the first argument is a split of a given text and, according to the split value, it will return every characters of the a given value.  I dont understand here how can we add a column of a table with  that split ?

Maybe ma questions are stupid because I'm very new in PowerApps .. but if somoene can help me to understand that I would be very happy 🙂

Thanks to all for your help and ... patience 🙂 

[gabibalaban · Accepted solution]

@forstera ,

Let us split the formula to understand better what is going on. I'll start from middle of the formula:

LookUp(
  colCharsWidth;
  CharFont = Self.Font && CharWeight = Self.FontWeight && Char = Result
).Size

colCharsWidth - is most probably a collection defined on OnStart property of the app (please check if i'm right) 

The lookup function checks inside this collection to find a record that met the condition and ".Size" get the value of this "Size" record column. 

AddColumns(
       Split(
             Self.Text;
             ""
            );
            "Size";
             LookUp(
                 colCharsWidth;
                 CharFont = Self.Font && CharWeight = Self.FontWeight && Char = Result
                 ).Size
);

Split function() returns a table with one column called Result and as you already said split in chars the value of property text of the current control.

To the table resulted from Split() function, a column is added with the name Size and for each row with the value resulted as I described above. 

Until now, the function result is a table with 2 columns Result (containing each char from the text property) an Size 

(containing the Size value as it is defined in colCharsWidth collection).

Next step, SUM function add the values Size collection from each row in the table.

SumFunctionResult* Self.Size + Self.PaddingLeft + Self.PaddingRight + 2

The result of sum function is multiplied /added with some constant values of the current control. 

Hope it helps !

[forstera]

Wow,

Thanks very much ! This helped me very much !

Yes you're right. ColcharWidth is a collection but as I'dont have admin right on that, I can't see the content..

let's say that this collection is not empty ...

Then,  I should have understood the the return of the split function is a table which will be the source for the AddColumn function 🙂 

I just now have to understand the entire formula but there's something that is strange to me : 

According to the formula here above : Sum (...) *Self.Size + Self.PaddingLeft + Self.PaddingRight + 2;

The size value of my field below is set to 0.  So the result of the multiplication here above should always be 0 or ? 

What do you mean ? 

Many many thanks 🙂

[forstera]

Hmmm, 

i realized my last post is completely wrong. 

I assume that the self.size attribute tells us the size of the writing; is this correct ?

Thanks very much to all