更改图像android的颜色

Question

I want to change the color of image that exist in imageview. i got the image from imageview in Bitmap object and applied colormatrix on it. The problem is that , once i change the color of image, it doesn't change bt override the previous color, I want that , when i change the color, the previous color of image should be removed and any specific color that i choose is applied.

i am using the following code to do that...

void setImageColor(RGBColor rgbcolor,ImageView view)//,Bitmap sourceBitmap)
    {   
        view.setDrawingCacheEnabled(true);
        Bitmap sourceBitmap = view.getDrawingCache();
        if(sourceBitmap!=null)
        {
        float R = (float)rgbcolor.getR();
        float G = (float)rgbcolor.getG();
        float B =  (float)rgbcolor.getB();

        Log.v("R:G:B",R+":"+G+":"+B);       

        float[] colorTransform =
        { R/255f, 0, 0, 0, 0, // R color
          0, G/255f, 0, 0, 0, // G color
          0, 0, B/255f, 0, 0, // B color
          0, 0, 0, 1f, 0f
        };                  

        ColorMatrix colorMatrix = new ColorMatrix();
        colorMatrix.setSaturation(0f); //Remove Colour 

        colorMatrix.set(colorTransform); 
        ColorMatrixColorFilter colorFilter = new ColorMatrixColorFilter(colorMatrix);
        Paint paint = new Paint();
        paint.setColorFilter(colorFilter);   

        Bitmap mutableBitmap = sourceBitmap.copy(Bitmap.Config.ARGB_8888, true);
        view.setImageBitmap(mutableBitmap);
        Canvas canvas = new Canvas(mutableBitmap);
        canvas.drawBitmap(mutableBitmap, 0, 0, paint);      
        }
        else
            return;
    }

Answer 1

Declare a static sourceBitmap and do this only once: Bitmap sourceBitmap = view.getDrawingCache(); let's say in onResume() of your activity (or when you change the image from ImageView).

And your function should be:

void setImageColor(RGBColor rgbcolor, ImageView view, Bitmap sourceBitmap) {
    if (sourceBitmap == null) return;

    float r = (float) rgbcolor.getR(),
          g = (float) rgbcolor.getG(),
          b = (float) rgbcolor.getB();

    Log.v("R:G:B", r + ":" + g + ":" + b);       

    float[] colorTransform =
    {       
        r/255, 0    , 0    , 0, 0,  // R color
        0    , g/255, 0    , 0, 0,  // G color
        0    , 0    , b/255, 0, 0,  // B color
        0    , 0    , 0    , 1, 0
    };

    ColorMatrix colorMatrix = new ColorMatrix();
    colorMatrix.setSaturation(0f); // Remove colour 
    colorMatrix.set(colorTransform); 

    ColorMatrixColorFilter colorFilter = new ColorMatrixColorFilter(colorMatrix);

    Paint paint = new Paint();
    paint.setColorFilter(colorFilter);   

    Bitmap mutableBitmap = sourceBitmap.copy(Bitmap.Config.ARGB_8888, true);
    view.setImageBitmap(mutableBitmap);

    Canvas canvas = new Canvas(mutableBitmap);
    canvas.drawBitmap(mutableBitmap, 0, 0, paint);      
}

This way you will hold the unaltered image and apply the filters on the original.