OutOfMemory Error using ImageView

Question

i\'m trying to make a wallpaper set app using ImageView. I know its hard to display a bunch of images (especially when images are 1920x1080), what i did was to make other bu

Answer 1

Move the images to a new folder called "drawable-nodpi".

Reason

Images in different drawable folders are opened by the android system with different memory allocations, hdpi means it will take a LOT of memory even if the image is tiny.

drawable-nodpi is the best for memory saving.

Answer 2

To fix OutOfMemory you should do something like that:

BitmapFactory.Options options=new BitmapFactory.Options();
options.inSampleSize = 8;
Bitmap preview_bitmap=BitmapFactory.decodeStream(is,null,options);

This inSampleSize option reduces memory consumption.

Here's a complete method. First it reads image size without decoding the content itself. Then it finds the best inSampleSize value, it should be a power of 2. And finally the image is decoded.

//decodes image and scales it to reduce memory consumption
private Bitmap decodeFile(File f){
try {
    //Decode image size
    BitmapFactory.Options o = new BitmapFactory.Options();
    o.inJustDecodeBounds = true;
    BitmapFactory.decodeStream(new FileInputStream(f),null,o);

    //The new size we want to scale to
    final int REQUIRED_SIZE=70;

    //Find the correct scale value. It should be the power of 2.
    int scale=1;
    while(o.outWidth/scale/2>=REQUIRED_SIZE && o.outHeight/scale/2>=REQUIRED_SIZE)
        scale*=2;

    //Decode with inSampleSize
    BitmapFactory.Options o2 = new BitmapFactory.Options();
    o2.inSampleSize=scale;
    return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
} catch (FileNotFoundException e) {}
return null;
}