ImageView be a square with dynamic width?

Question

I have a GridView with ImageViews inside. I have 3 of them for each row. I can set correctly the width with WRAP_CONTENT and scaleType = CENTER_CROP, but I don't know how to set the ImageView's size to be a square. Here's what I did until now, it seems to be ok except the height, that is "static":

imageView = new ImageView(context);     
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setLayoutParams(new GridView.LayoutParams(GridView.LayoutParams.WRAP_CONTENT, 300));

I'm doing it inside an adapter.

Answer 1

Several of the previous answers are perfectly sufficient. I'm just adding a small optimization to both @Andro Selva and @a.bertucci's solutions here:

It's a tiny optimization, but checking that the width and the height are different could prevent another measurement pass.

public class SquareImageView extends ImageView {

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

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

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

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

        int width = getMeasuredWidth();
        int height = getMeasuredHeight();

        // Optimization so we don't measure twice unless we need to
        if (width != height) {
            setMeasuredDimension(width, width);
        }
    }

}

Answer 2

Here all are unnecessary calling its superclass for onMeasure. Here is my implementation

@Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        int width = MeasureSpec.getSize(widthMeasureSpec);
        int height = MeasureSpec.getSize(heightMeasureSpec);
        int size = Math.min(width, height);
        setMeasuredDimension(size, size);
    }