SquareFrameLayout.java

package com.simplecity.amp_library.ui.views;

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

import com.simplecity.amp_library.R;

/**
 * A custom {@link android.widget.FrameLayout} that is sized to be a perfect square
 */
public class SquareFrameLayout extends FrameLayout {

    boolean widthDominant = true;

    /**
     * Constructor for <code>SquareFrameLayout</code>
     *
     * @param context The {@link android.content.Context} to use
     * @param attrs   The attributes of the XML tag that is inflating the view
     */
    public SquareFrameLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

        TypedArray a = context.getTheme().obtainStyledAttributes(
                attrs,
                R.styleable.SquareFrameLayout,
                0, 0);

        if (a.hasValue(R.styleable.SquareFrameLayout_dominant_measurement)) {
            int value = a.getInt(R.styleable.SquareFrameLayout_dominant_measurement, 0);
            widthDominant = value == 0;
        }

        a.recycle();
    }

    @Override
    public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        setMeasuredDimension(widthDominant ? getMeasuredWidth() : getMeasuredHeight(), widthDominant ? getMeasuredWidth() : getMeasuredHeight());
    }

}