由於 Android 的 icon 四周圓角裁剪時為透明所以在分享到微信和 QQ 好友中呈現黑邊。

程式碼解決辦法

Bitmap bmp = BitmapFactory.decodeResource(instance.getResources(),R.drawable.icon);
UMImage img = new UMImage(m_Context, changeColor(bmp));

//bitmap中的透明色用白色替換
public static Bitmap changeColor(Bitmap bitmap) {
    if (bitmap == null) {
        return null;
    }
    int w = bitmap.getWidth();
    int h = bitmap.getHeight();
    int[] colorArray = new int[w * h];
    int n = 0;
    for (int i = 0; i < h; i++) {
        for (int j = 0; j < w; j++) {
            int color = getMixtureWhite(bitmap.getPixel(j, i));
            colorArray[n++] = color;
        }
    }
    return Bitmap.createBitmap(colorArray, w, h, Bitmap.Config.ARGB_8888);
}

//獲取和白色混合顏色
private static int getMixtureWhite(int color) {
    int alpha = Color.alpha(color);
    int red = Color.red(color);
    int green = Color.green(color);
    int blue = Color.blue(color);
    return Color.rgb(getSingleMixtureWhite(red, alpha), getSingleMixtureWhite(green, alpha),
            getSingleMixtureWhite(blue, alpha));
}

// 獲取單色的混合值
private static int getSingleMixtureWhite(int color, int alpha) {
    int newColor = color * alpha / 255 + 255 - alpha;
    return newColor > 255 ? 255 : newColor;
}