Two dimension array in QML...

aekam

Hello,
I was wondering about how to use two dimension arrays in QML.
One way i found is,
@
property variant myArray: [[0, 1, 2], [7, 8, 9]]
@

now to print it,
@
// prints 0
console.log ("array element is = " + myArray[0][0])
// prints 9
console.log ("array element is = " + myArray[1][2])
@

is this right way to create and access it.??

favoritas37

Yeah it is quite fine.

A more dynamic way would be:

{{{

var 2dArray = new Array(5);

2dArray[ 0 ] = newArray(5);
2dArray[ 1 ] = newArray(5);
//and on and on as many as you want

//Then print just like the code you posted
}}}

aekam

Interesting... :) thanks...

blakxu00

I got an error
TypeError: Result of expression 'maintable[i]' [undefined] is not an object.

my code is

@var i,j
maintable = new Array(3);
for(i=0;i<3;i++){
maintable[i]=new Array(3);
for(j=0;j<3;j++){
maintable[i][j]="."
}
}
@

favoritas37

I will suppose you mean:
@
var i,j;
var maintable = new Array(3);
for(i=0;i<3;i++){
maintable[i]=new Array(3);
for(j=0;j<3;j++){
maintable[i][j]="."
}
}
@

This code looks and works fine.

Do you use the maintable somewhere else in your code?

blakxu00

Thanks you favoritas37

the maintable is defined as variant

and Yes I use it in my code but that where the compiler points two,

blakxu00

Dear

Solved,

@var maintab
maintab = new Array(3);
for(i=0;i<3;i++){
maintab[i]=new Array(3);
for(j=0;j<3;j++){
maintab[i][j]="."
}
}
maintable=maintab@

and thank you favoritas37

chrisadams

Please be aware that when you use a variant property to store your array, it is actually being converted to a QVariant. Accessing it from the QVariant property will incur some conversion overhead. In Qt5/QtQuick2, you should use the "var" property type instead - but this property type is not available in Qt4/QtQuick1.

Cheers,
Chris.

blakxu00

Thanks chris for the tip