CircleView.java

package org.petabytes.awesomeblogs.widget;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.support.annotation.ColorRes;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.util.AttributeSet;
import android.view.View;

import org.petabytes.awesomeblogs.R;

public class CircleView extends View {

    private Paint paint;

    public CircleView(@NonNull Context context) {
        this(context, null);
    }

    public CircleView(@NonNull Context context, @Nullable AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public CircleView(@NonNull Context context, @Nullable AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);
        init(attrs, defStyleAttr);
    }

    private void init(@Nullable AttributeSet attrs, int defStyleAttr) {
        TypedArray a = getContext().obtainStyledAttributes(attrs, R.styleable.CircleView, defStyleAttr, 0);
        paint = new Paint();
        paint.setFlags(Paint.ANTI_ALIAS_FLAG);
        paint.setStyle(Paint.Style.FILL);
        paint.setColor(a.getColor(R.styleable.CircleView_fillColor, getContext().getResources().getColor(R.color.colorAccent)));
        a.recycle();
    }

    public void setFillColor(@ColorRes int color) {
        paint.setColor(getContext().getResources().getColor(color));
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, widthMeasureSpec);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        canvas.drawCircle(getWidth() / 2, getHeight() / 2, getWidth() / 2, paint);
    }
}