opengl es how to set boolean in shader

I want to set boolean value in my fragment shader beacuse i need to recognize when to color objects by multiplying. but i dont know how to acess this boolean variable textured from java code. Project is created in java for android, using opengl es 3.0.

precision mediump float;
uniform vec4 vColor;
uniform bool textured;
uniform sampler2D uTexture;
varying vec2 vTexCoordinate;

void main(){
    if(textured){
        gl_FragColor = texture2D(uTexture, vTexCoordinate);
        gl_FragColor *= vColor;
    } else {
        gl_FragColor = vColor;
    }
}

I recommend to use an int rather than a bool: if (textured != 0)

Alternatively you can pass a floating point value which weights the texture:

precision mediump float;
uniform vec4 vColor;
uniform float textured;
uniform sampler2D uTexture;
varying vec2 vTexCoordinate;

void main()
{
    gl_FragColor = 
       vColor * mix(vec4(1.0), texture2D(uTexture, vTexCoordinate), textured);
}

mix linearly interpolate between two values. Look at the expression:

gl_FragColor = 
    vColor * mix(vec4(1.0), texture2D(uTexture, vTexCoordinate), textured);

If textured == 0.0, the color is multiplied by vec4(1.0):

gl_FragColor = vColor * vec4(1.0);

If textured == 1.0, then the color is multiplied by the color returned from the texture lookup:

gl_FragColor = vColor * texture2D(uTexture, vTexCoordinate);

If 0.0 < textured < 1.0, then vec4(1.0) and the texture color are interpolated linearly.

Furthermore be careful when you look up a texture in a condition statement. See OpenGL ES 1.1 Full Specification - 6 Texture Accesses; page 110:

> Accessing mip-mapped textures within the body of a non-uniform conditional block gives an undefined value. A non-uniform conditional block is a block whose execution cannot be determined at compile time.