How do I set the R, G, B and Alpha components of a color?

Question

There are 3 integer values that makes up a RGB value, and also i have the Alpha component value of the color. how do i set these 4 values to get the desired colour

Set these values in what context? what API, the `Color` class? — Sean Owen, Jul 18 '11 at 14:11

dacwe · Accepted Answer · 2011-07-18T14:13:56.030

22

You can create a Color object (the values should either be ints between 0-255 or floats between 0f-1f:

Color c = new Color(red, green, blue, alpha);

If you want to paint an image with that color:

BufferedImage image = new BufferedImage(300, 200, BufferedImage.TYPE_INT_ARGB);
Graphics graphics = image.getGraphics(); 
graphics.setColor(c);
graphics.fillRect(50, 50, 100, 100);
graphics.dispose();

If you only want to set a pixel (color model must be ARGB):

image.setRGB(50, 50, c.getRGB());

edited Jul 18 '11 at 14:13

answered Jul 18 '11 at 14:08

dacwe

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How do i change the already set RGBA values?. Is there a `c.setRGB(red,green,blue,alpha)` function? – Brethlosze Mar 29 '15 at 08:04
`setRGB(x, y, rgba)` takes an integer composite of red, green, blue and _alpha_. Create the color with transparency using `rgba = new Color(r, g, b, alpha).getRGB()` – dacwe Mar 31 '15 at 06:21

score 0 · Answer 2 · answered Mar 10 '23 at 12:29

0

you can use :

panel1.setBackground(new Color(0.0f, 0.0f, 0.0f,0.5f));

answered Mar 10 '23 at 12:29

Yasmine El

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score -1 · Answer 3 · answered Apr 17 '15 at 15:13

-1

you can also use

int colorToSet = Color.argb(alpha, red, green, blue); to set Alpha

answered Apr 17 '15 at 15:13

Zar E Ahmer

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How do I set the R, G, B and Alpha components of a color?

3 Answers3

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