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Android GalleryView Recycling

I use GalleryView with ~ 40 images, and so slowly because there is no recycling ...

Anyone can show me the basic utility before GalleryViewby the method getView.

public class ImageAdapter extends BaseAdapter {
    int mGalleryItemBackground;
    private Context mContext;

    private Integer[] mImageIds = {
            R.drawable.sample_1,
            R.drawable.sample_2,
            R.drawable.sample_3,
            R.drawable.sample_4,
            R.drawable.sample_5,
            R.drawable.sample_6,
            R.drawable.sample_7
    };

    public ImageAdapter(Context c) {
        mContext = c;

        TypedArray a = c.obtainStyledAttributes(R.styleable.HelloGallery);
        mGalleryItemBackground = a.getResourceId(
                R.styleable.HelloGallery_android_galleryItemBackground, 0);
        a.recycle();
    }

    public int getCount() {
        return mImageIds.length;
    }

     public Object getItem(int position) {
        return position;
    }

    public long getItemId(int position) {
        return position;
    }

    public View getView(int position, View convertView, ViewGroup parent) {
        ImageView i = new ImageView(mContext);

        i.setImageResource(mImageIds[position]);
        i.setLayoutParams(new Gallery.LayoutParams(150, 100));
        i.setScaleType(ImageView.ScaleType.FIT_XY);
        i.setBackgroundResource(mGalleryItemBackground);

        return i;
    }
}
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2 answers

Instead of creating a new one ImageView, getViewyou should convert convertViewto the desired view. Here is an example of one way to do this:

public View getView(int position, View cv, ViewGroup parent) {

    if (! convertView istanceof ImageView)
    {
        ImageView cv = new ImageView(mContext);
        cv.setLayoutParams(new Gallery.LayoutParams(150, 100));
        cv.setScaleType(ImageView.ScaleType.FIT_XY);
        cv.setBackgroundResource(mGalleryItemBackground);

    }
    cv.setImageResource(mImageIds[position]);

    return cv;
}

Just convert the convertView to whatever you want, but first make sure it has the correct look.

. . , 500x500 , res/drawable, 125x125 . , , . , ,

int maxSize = 125; // make 125 the upper limit on the bitmap size
int resId; // points to bitmap in res/drawable

BitmapFactory.Options opts = new BitmapFactory.Options();
opts.inJustDecodeBounds = true; // Only get the bitmap size, not the bitmap itself
BitmapFactory.decodeResource(c.getResources(), resId, opts);

int w = opts.outHeight, h = opts.outHeight;
int maxDim = (w>h)?w:h; // Get the bigger dimension

, , , . 500x500, 125x125, 1 4 , int inSample = 500/125;

int inSample = maxDim/maxSize; 

opts = new BitmapFactory.Options();
opts.inSampleSize = inSample;

, .

Bitmap b = BitmapFactory.decodeResource(c.getResources(), resId, opts);

, . opts.inSampleSize 1, 500x500.

+5

Gallery , null convertView. , getView, convertView, , . .

. "" . EcoGallery , Gallery, . : (1) View. (2) "", , , Gallery.

: EcoGallery, 3 java , , 2 xml SDK .

+4

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