#XOJO ARRAY NUMBER OF VALUES CODE#

Note that if the column length is not long enough, we only get the start value in the array. Then in the result column, in put the formula =ROW(INDIRECT(start&”:”&end))).We need to state the start and end of the array as shown in the example above.ROW and INDIRECT functions are fundamental when we want to create an array of numbers.Both the FontUsers reference to the array and the one stored in the module refer to the same array and so altering one alters the other.We can use the ROW and INDIRECT functions to create an array of numbers, e.g. They appear to have magically disappeared – but they haven’t. So the next time you call the method they are not present.

#XOJO ARRAY NUMBER OF VALUES CODE#

What happens? The code calling the FontList method gets back a reference to the exact same array stored in the module, and then proceeds to remove entries from it. and lets get rid of all fonts with names starting with 'a'įor i as integer = fontlist.ubound downto 0 Something like the following: Module FontsĪnd then somewhere else in your application you have Sub FontUser()ĭim fontslist() as string = Fonts.FontList() But the users might alter the array that was returned. So changing either one will make it appear like the other has changed as well.Īs I said earlier, most times you have to use New to access a variable that is a reference type. However, arrays are reference types so you have to be careful with them. Suppose you have a module that returns an array and the array is supposed to be set up once and then reused in many places. This results in both p1 and p2 now containing the same address – they both refer to the same underlying Picture object.

The last line will take the address that is in the location for P1 and put it into the location set aside for P2.

The second line will allocate enough memory to hold the picture and then put the correct address of this block of memory into the memory address set aside in step 1 for P1.

In the DIM line, set aside memory locations to hold pointers (references), one for each of p1 and p2.

While many expect that this will “copy” the picture from p1 and create a new one for P2 thats not what happens at all. But there are a few that might catch you unaware. And the difference between value types and reference types causes no end of confusion with code like this: dim p1, p2 as Picture Most reference types in Xojo are reasonably easy to identify – you have to use New to create one from scratch.

the second line will allocate enough memory to hold the picture somewhere else in memory and then put the correct address of this block of memory into the memory address set aside in step 1.

set aside a memory location, in the dim line, to hold a pointer (reference).

They have a pointer to some other memory area that actually holds the data.

Reference types do not store the data in the memory address assigned to the variable. Note: This is not the same as “ ByRef” in a method parameter declaration although it’s related. the second line will put the correct binary representation of “32” into the memory address set aside in step 1Īnd then there are reference types.

set aside a memory location, in the dim line, to hold an integer.In Xojo this includes Integers of all kinds, Doubles or Colors. When you put a value into one, the memory address for this variable is set to whatever the correct binary representation for the value is. When I ask “What kind of variable are you?” I don’t mean “Are you an Integer, a String, a Variant, an Object?”. I am asking “are you a value type or a reference type?”. What’s the difference between the two?

Xojo array number of values