Android - Scaling ImageView so that it's always 100 dip in width - android-imageview

Question

I'm trying to get an ImageView to have a specific width (let's say 100dips) but to scale so that the height is whatever value that maintains ratio, so if 4:3 then 75 dips, if 4:5 then 120 dips, etc.
I've tried a few things, but nothing is working. This is my current attempt:
<ImageView
android:id="#+id/image"
android:layout_height="wrap_content"
android:layout_width="100dip"
android:adjustViewBounds="true"
android:src="#drawable/stub"
android:scaleType="fitCenter" />
The wrap_content for height didn't improve things, it just made the entire image smaller (but did maintain aspect ratio). How can I Accomplish what I'm trying to do?

Answer 1

Add the follwing class to your project and change your layout like this
View
<my.package.name.AspectRatioImageView
android:layout_centerHorizontal="true"
android:src="#drawable/my_image"
android:id="#+id/my_image"
android:layout_height="wrap_content"
android:layout_width="100dp"
android:adjustViewBounds="true" />
Class
package my.package.name;
import android.content.Context;
import android.util.AttributeSet;
import android.widget.ImageView;
/**
* ImageView which scales an image while maintaining
* the original image aspect ratio
*
*/
public class AspectRatioImageView extends ImageView {
/**
* Constructor
*
* #param Context context
*/
public AspectRatioImageView(Context context) {
super(context);
}
/**
* Constructor
*
* #param Context context
* #param AttributeSet attrs
*/
public AspectRatioImageView(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* Constructor
*
* #param Context context
* #param AttributeSet attrs
* #param int defStyle
*/
public AspectRatioImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
/**
* Called from the view renderer.
* Scales the image according to its aspect ratio.
*/
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int width = MeasureSpec.getSize(widthMeasureSpec);
int height = width * getDrawable().getIntrinsicHeight() / getDrawable().getIntrinsicWidth();
setMeasuredDimension(width, height);
}
}