[Qgis-user] Vector symbology from attribute table

[Siki Zoltan]

Hi Leo,

AFAIK to have the classification in the legend you must use a tematic map 
type, e.g. make a categorized thematic map on the class attribute and set 
manually the color for the classes than you can create a layer style file 
(qml) from the properties/style dialog pushing the save style button.
Later you can use the style file, but if the rgb values are changed it 
doesn't work :(
An other solution can be to write a python script to collect the different 
rgb values from he attribute table and generate dinamically the style file 
or the thematic classes.

Zoltan

On Tue, 5 Aug 2014, Leo Kris Palao wrote:

> Hi Zoltan,
>
> I tried it and it was working, it defines well the symbology of my vector
> layer. However, there is a little bit of problem. In my legend items it
> only create one color (black). the color scheme of my legend doesn't seem
> to follow the color combinations that I set in my attribute table. it would
> be better if the color scheme of my attribute table will be reflected also
> in my legend items.
>
> This is how I encoded the color codes in my attribute table:
> class                                  color (R, G, B)
> 1                                         197, 197, 197
>
> Thanks,
> -Leo
>
>
> On Mon, Aug 4, 2014 at 5:31 PM, Siki Zoltan <siki at agt.bme.hu> wrote:
>
>> Dear Leo,
>>
>> you can do it in the properties dialog of the layer.
>> For example if you have a polygon layer, and the fill color is stored in
>> the attribute table of the layer than
>> 1. open properties dialog of the layer
>> 2. select style tab (left)
>> 3. click on "Simple fill" under symbol layers (if you can't see Simple
>> fill, click on the triangle before Fill to extend the tree)
>> 4. click on data defined properties... button
>> 5. you can give an attribute or an expression of attributes to define the
>> fill color
>>
>> I hope it helps you,
>> Zoltan
>>
>>
>> On Mon, 4 Aug 2014, Leo Kris Palao wrote:
>>
>>  Hi QGIS users,
>>>
>>> Is there a way to automatically define the symbology of vector layer using
>>> a column in the attribute table that defines the RGB?
>>>
>>> I want to do this to have a uniform color coding for each land use types.
>>> Some land use types might have more or less classes than for each
>>> administrative boundary. I am thinking if I can encode the RGB values in
>>> my
>>> attribute table and later use it to define my symbology.
>>>
>>> Thanks for any help and advice,
>>> -Leo
>>>
>>>
>