Expand ImageView to maximum possible maintaining aspect ratio in Android

Question

I have found lots of answers in this site but they are not working or just for single cases. In my case:

I would like to load an image and show it into a ImageView.
The width of the ImageView must be the maximum possible: parent layout width.
The height must be the one that allows re-scale the image maintaining the aspect ratio.

How do achieve this? Here is my layout with the ImageView inside (currently I have been using fitXY but the image does not preserve the aspect ratio, even if using adjustViewBounds:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/layoutPictureGalleryItem"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="5dp"
    android:background="#E0E0DE"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/imageView"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:scaleType="fitXY"
        tools:ignore="ContentDescription" />

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical"
        android:background="#FFFFFF" >

        <TextView
            android:id="@+id/textName"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="esto es una prueba para ver cómo queda el layout"
            android:textColor="#000000"
            android:textSize="12sp"
            android:typeface="serif"
            android:padding="2dp" />

        <TextView
            android:id="@+id/textDescription"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:visibility="gone"
            android:padding="2dp" />

    </LinearLayout>

</LinearLayout>

hordurh hordurh · Accepted Answer · 2013-08-28T15:11:30

Use this widget instead of your imageview and let the width match parent:

package com.myapp.widgets;

import android.content.Context;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.ImageView;

public class ResizableImageView extends ImageView {

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

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

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

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec)
{
    Drawable drawable = getDrawable();
    if (drawable != null)
    {
        int width =  MeasureSpec.getSize(widthMeasureSpec);
        int diw = drawable.getIntrinsicWidth();
        if (diw > 0)
        {
            int height = width * drawable.getIntrinsicHeight() / diw;
            setMeasuredDimension(width, height);
        }
        else
            super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }
    else
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}
}

Expand ImageView to maximum possible maintaining aspect ratio in Android

1 Answers