SquareTextView.java

import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;

public class SquareTextView extends android.support.v7.widget.AppCompatTextView {

  public SquareTextView(Context context) {
    super(context);
  }

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

  public SquareTextView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
  }

  @Override
  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    int width = this.getMeasuredWidth();
    int height = this.getMeasuredHeight();
    int size = Math.max(width, height);
    int widthSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
    int heightSpec = MeasureSpec.makeMeasureSpec(size, MeasureSpec.EXACTLY);
    super.onMeasure(widthSpec, heightSpec);
  }
}