CornerButton.java

public class CornerButton extends TextViewCustomFont {

    GradientDrawable mDrawable;
    private int mBgColor = Color.WHITE;
    private int mBgColorSelected = Color.WHITE;
    private int mBgColorDisabled = Color.LTGRAY;
    private boolean mSelected = false;
    private int mCornerRadius = 0;
    private int mStrokeWidth = 0;
    private int mStrokeColor = Color.TRANSPARENT;
    private Drawable mBackgroundDrawable;

    public CornerButton(Context context) {
        super(context);
        init(null);
    }

    public CornerButton(Context context, AttributeSet attrs) {
        super(context, attrs);
        init(attrs);
    }

    public CornerButton(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(attrs);
    }

    private void init(AttributeSet attrs) {
        mDrawable = new GradientDrawable();

        // fetch attributes
        TypedArray a = getContext().getTheme()
                .obtainStyledAttributes(attrs, R.styleable.CornerButton, 0, 0);
        try {
            mBgColor = a.getColor(R.styleable.CornerButton_bgColor, mBgColor);
            mBgColorSelected = BitmapUtils.addColor(mBgColor, 0.85f);
            mBgColorDisabled = BitmapUtils.addAlpha(mBgColor, 0.65f);
            mBgColorSelected =
                    a.getColor(R.styleable.CornerButton_bgColorSelected, mBgColorSelected);
            mBgColorDisabled =
                    a.getColor(R.styleable.CornerButton_bgColorDisabled, mBgColorDisabled);
            mCornerRadius = a.getDimensionPixelSize(R.styleable.CornerButton_corner, mCornerRadius);
            mSelected = a.getBoolean(R.styleable.CornerButton_selected, mSelected);
            mStrokeWidth = a.getDimensionPixelSize(R.styleable.CornerButton_cornerStrokeWidth,
                    mStrokeWidth);
            mStrokeColor = a.getColor(R.styleable.CornerButton_cornerStrokeColor, mStrokeColor);
            mBackgroundDrawable = a.getDrawable(R.styleable.CornerButton_bgDrawable);
        } finally {
            a.recycle();
        }

        setClickable(true);

        refresh();
    }

    public void setBackgroundColor(int color) {
        setBackgroundColor(color, color);
    }

    public void setBackgroundColor(int color, int colorSelected) {
        this.mBgColor = color;
        this.mBgColorSelected = colorSelected;
        refresh();
    }

    public void setCorner(int corner) {
        this.mCornerRadius = corner;
        refresh();
    }

    @Override
    public void setSelected(boolean selected) {
        super.setSelected(selected);
        this.mSelected = selected;
        refresh();
    }

    @Override
    public void setEnabled(boolean enabled) {
        super.setEnabled(enabled);
        refresh();
    }

    private void refresh() {
        if (!isEnabled()) {
            mDrawable.setColor(mBgColorDisabled);
            setBackground(mDrawable);
        } else if (mBackgroundDrawable != null) {
            setBackground(mBackgroundDrawable);
        } else {
            mDrawable.setColor(mSelected ? mBgColorSelected : mBgColor);
            mDrawable.setCornerRadius(mCornerRadius);
            mDrawable.setStroke(mStrokeWidth, mStrokeColor);
            mDrawable.setShape(GradientDrawable.RECTANGLE);
            setBackground(mDrawable);
        }
        invalidate();
    }

    @Override
    public void setPressed(boolean pressed) {
        super.setPressed(pressed);
        this.mSelected = pressed;
        refresh();
    }
}

/**
     * Transform color to darker or lighter
     *
     * @param color input color
     * @param factor < 1: darker, > 1: lighter
     */
    public static int addColor(int color, float factor) {
        int a = Color.alpha(color);
        int r = Math.round(Color.red(color) * factor);
        int g = Math.round(Color.green(color) * factor);
        int b = Math.round(Color.blue(color) * factor);
        return Color.argb(a, Math.min(r, 255), Math.min(g, 255), Math.min(b, 255));
    }

    /**
     * Transform color to darker or lighter (alpha)
     *
     * @param color input color
     * @param factor < 1: opacity, > 1: transparent
     */
    public static int addAlpha(int color, float factor) {
        int a = Math.round(Color.alpha(color) * factor);
        int r = Color.red(color);
        int g = Color.green(color);
        int b = Color.blue(color);
        return Color.argb(Math.min(a, 255), r, g, b);
    }