i have a question about using GalleryView.
At first, i set five "default images" to show from drawable directory.
But after, i want to run an Async Task in which i download the images, save them and show them in the gallery.
For that i created the following Adapter:
public class ImageAdapter extends BaseAdapter {
int mGalleryItemBackground;
private Context mContext;
private ArrayList<Integer> mImageIds = new ArrayList<Integer>();
private ArrayList<Drawable> mImageDrawables = new ArrayList<Drawable>();
public ImageAdapter(Context c) {
mContext = c;
TypedArray a = obtainStyledAttributes(R.styleable.Gallery1);
mGalleryItemBackground = a.getResourceId(
R.styleable.Gallery1_android_galleryItemBackground, 0);
a.recycle();
}
public void setPlaces(int count) {
for (int i = 0; i < count; i++) {
mImageIds.add(R.drawable.tournoimg);
mImageDrawables.add(null);
}
}
public void setDrawable(String resource, int position) {
Drawable image = Drawable.createFromPath(resource);
mImageDrawables.add(position, image);
}
public int getCount() {
return mImageIds.size();
}
public Object getItem(int position) {
return position;
}
public long getItemId(int position) {
return position;
}开发者_如何学编程
public View getView(int position, View convertView, ViewGroup parent) {
ImageView i = new ImageView(mContext);
if (mImageDrawables.get(position) == null)
i.setImageResource(mImageIds.get(position));
else
i.setImageDrawable(mImageDrawables.get(position));
i.setLayoutParams(new Gallery.LayoutParams(60, 78));
i.setScaleType(ImageView.ScaleType.FIT_XY);
i.setBackgroundResource(mGalleryItemBackground);
return i;
}
}
}
and the following Async Task
private class FillImages extends AsyncTask<ArrayList<Place>, Void, Void> {
protected Void doInBackground(ArrayList<Place>... listplaces) {
ArrayList<Place> places = listplaces[0];
Iterator<Place> it = places.iterator();
int position = 0;
while (it.hasNext()) {
Place p = it.next();
saveImage(p.getImage(), p.getURLImage());
// Gallery g = (Gallery) findViewById(R.id.gallery);
mImageAdapter.setDrawable(p.getImage(), position);
position++;
mImageAdapter.notifyDataSetChanged();
}
return (null);
}
But when i run it i have this error: Caused by: android.view.ViewRoot$CalledFromWrongThreadException: Only the original thread that created a view hierarchy can touch its views.
Any idea?
Thanks
You should implement onPostExecute()
and move any code that interacts with the UI (perhaps notifyDataSetChange()
) to that method. Android requires that interaction with the GUI happen from the UI thread.
For that you have to put this code into onPostExecute() method of Async task :
ArrayList<Place> places = listplaces[0];
Iterator<Place> it = places.iterator();
int position = 0;
while (it.hasNext()) {
Place p = it.next();
saveImage(p.getImage(), p.getURLImage());
// Gallery g = (Gallery) findViewById(R.id.gallery);
mImageAdapter.setDrawable(p.getImage(), position);
position++;
mImageAdapter.notifyDataSetChanged();
}
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