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You have completed Object-Oriented JavaScript: Challenge!
You have completed Object-Oriented JavaScript: Challenge!
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See the solution for the createSpaces() method.
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Well done,
0:00
I hope you enjoyed working through the
createSpaces method in the Board.js file.
0:01
Let's take a look at the solution.
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First, you can see the documentation
written for this method.
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There's a summary line explaining that
this method would generate a 2D array of
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space objects.
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And then there's a line indicating
that an array will be returned,
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followed by a description of the array.
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The first step in this method is to
create a variable called spaces that
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holds an empty array.
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This is the variable that will
eventually be returned from the method.
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After we create the variable,
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we can go through the business
of populating the array.
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We know that the returned
array should be a 2D array.
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This means it's an array whose
elements are also arrays.
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The variable will hold
an array of columns,
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where each column is an array
of individual space objects.
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By setting it up this way, we can access
each column of spaces as a whole,
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which will be really helpful when
it comes time to drop tokens.
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So with that in mind,
the first step is to create a for
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loop that iterates through
the number of columns.
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Remember, the number of columns wias
set in the constructor method and
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can be accessed using this.columns.
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Once we're inside the loop, we'll
declare a new variable called column.
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column is going to hold an array of the
individual space objects in that column.
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First, the column variable
gets set to an empty array.
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Then we write another for loop to
iterate through the rows of that column.
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Inside this nested for loop is where
the new space objects are created.
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We pass the space constructor
method the value for the x and
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y index of the for loops.
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On the next line, we push the newly
created space to the column array.
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On each iteration through this nested for
loop,
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another space is added to the column.
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After the column is complete, and
the nested for loop is finished,
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we push the entire column
back into the spaces array.
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Then the x index is increased by 1, and
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the process continues until the entire
board of spaces has been created.
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After that, we return our array.
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Don't forget about the method call,
though.
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At this point, we have to go
back to our constructor method.
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Make sure to adjust the spaces property so
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then instead of being set to an empty
array, it's set to the return value from
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a call to the createSpaces method,
like you see on the screen.
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To clarify, this means that when
the Board object is created,
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all of the space objects
are created as well.
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Okay, that was pretty tough.
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Nested for loops and two-dimensional
arrays can be complicated to think about.
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If you have any questions,
head over to the Treehouse community.
2:39
All right, only two steps left and
the foundation of our game is complete.
2:42
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