作業中のアプリケーションの 1 つに問題があります。ギャラリー ボタンを押して読み込みを開始すると、すべての写真が表示されますが、グリッド内の同じ写真が表示されますが、一度押すと、グリッドビューに表示されるのと同じ画像ではありません。以下は、私が作業しているコードといくつかの写真です。
イメージ アダプターのコードは次のとおりです。
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public Integer[] Tattoos = {
R.drawable.tattoo1, R.drawable.tattoo2,
R.drawable.tattoo3, R.drawable.tattoo4,
R.drawable.tattoo5, R.drawable.tattoo6,
R.drawable.tattoo7, R.drawable.tattoo8,
R.drawable.tattoo9, R.drawable.tattoo10,
R.drawable.tattoo11, R.drawable.tattoo12,
R.drawable.tattoo13, R.drawable.tattoo14,
R.drawable.tattoo15, R.drawable.tattoo16,
R.drawable.tattoo17, R.drawable.tattoo18,
R.drawable.tattoo19, R.drawable.tattoo20,
R.drawable.tattoo21, R.drawable.tattoo22,
R.drawable.tattoo23, R.drawable.tattoo24,
R.drawable.tattoo25, R.drawable.tattoo26,
R.drawable.tattoo27, R.drawable.tattoo28,
R.drawable.tattoo29, R.drawable.tattoo30,
R.drawable.tattoo31, R.drawable.tattoo32,
R.drawable.tattoo33, R.drawable.tattoo34,
R.drawable.tattoo35, R.drawable.tattoo36,
R.drawable.tattoo37, R.drawable.tattoo38,
R.drawable.tattoo39, R.drawable.tattoo40,
R.drawable.tattoo41, R.drawable.tattoo42,
R.drawable.tattoo43, R.drawable.tattoo44,
R.drawable.tattoo45, R.drawable.tattoo46,
R.drawable.tattoo47, R.drawable.tattoo48,
R.drawable.tattoo49, R.drawable.tattoo50,
R.drawable.tattoo51, R.drawable.tattoo52,
R.drawable.tattoo53, R.drawable.tattoo54,
R.drawable.tattoo55, R.drawable.tattoo56,
R.drawable.tattoo57, R.drawable.tattoo58,
R.drawable.tattoo59, R.drawable.tattoo60,
R.drawable.tattoo61, R.drawable.tattoo62,
R.drawable.tattoo63, R.drawable.tattoo64,
R.drawable.tattoo65, R.drawable.tattoo66,
R.drawable.tattoo67, R.drawable.tattoo68,
R.drawable.tattoo69, R.drawable.tattoo70,
R.drawable.tattoo71, R.drawable.tattoo72,
R.drawable.tattoo73, R.drawable.tattoo74,
R.drawable.tattoo75, R.drawable.tattoo76,
R.drawable.tattoo77, R.drawable.tattoo78,
R.drawable.tattoo79, R.drawable.tattoo80,
R.drawable.tattoo81, R.drawable.tattoo82
};
// Constructor
public ImageAdapter(Context c){
mContext = c;
}
public int getCount() {
return Tattoos.length;
}
public Object getItem(int position) {
return Tattoos[position];
}
public long getItemId(int position) {
return 0;
}
public View getView(int position, View convertView, ViewGroup parent) {
//This actually is a bad solution, because every time convertView is reused, you will still initialize new ImageView, which is wrong
//ImageView imageView = new ImageView(this.mContext);
//new BitmapWorkerTask(imageView).execute(Tattoos[position]);
//return imageView;
//Better solution
ImageView imageView = null;
if (convertView == null) {
imageView = new ImageView(this.mContext);
new BitmapWorkerTask(imageView).execute(Tattoos[position]);
//create new ImageView if it is not present and populate it with some image
} else {
imageView = (ImageView) convertView;
//re-use ImageView that already exists in memory
}
return imageView;
}
class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> {
private final WeakReference<ImageView> imageViewReference;
private int data = 0;
public BitmapWorkerTask(ImageView imageView) {
// Use a WeakReference to ensure the ImageView can be garbage collected
imageViewReference = new WeakReference<ImageView>(imageView);
}
// Decode image in background.
@Override
protected Bitmap doInBackground(Integer... params) {
data = params[0];
return decodeSampledBitmapFromResource(ImageAdapter.this.mContext.getResources(), data, 100, 100);
}
// Once complete, see if ImageView is still around and set bitmap.
@Override
protected void onPostExecute(Bitmap bitmap) {
if (imageViewReference != null && bitmap != null) {
final ImageView imageView = imageViewReference.get();
if (imageView != null) {
imageView.setImageBitmap(bitmap);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setLayoutParams(new GridView.LayoutParams(100, 70));
}
}
}
}
public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
int reqWidth, int reqHeight) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
public static int calculateInSampleSize(
BitmapFactory.Options options, int reqWidth, int reqHeight) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
// Calculate ratios of height and width to requested height and width
final int heightRatio = Math.round((float) height / (float) reqHeight);
final int widthRatio = Math.round((float) width / (float) reqWidth);
// Choose the smallest ratio as inSampleSize value, this will guarantee
// a final image with both dimensions larger than or equal to the
// requested height and width.
inSampleSize = heightRatio < widthRatio ? heightRatio : widthRatio;
}
return inSampleSize;
}
}
どんな助けでもいただければ幸いです