嗨，当我尝试使用此代码从 gridview 中的 imageurl 中复制图像时，它显示空指针异常，任何人都可以帮助我：我的代码是
public class Gridview extends Activity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_gridview);
GridView gridview = (GridView) findViewById(R.id.gridview);
gridview.setAdapter(new ImageAdapter(this));
}
public class ImageAdapter extends BaseAdapter{
private Context mContext;
private Integer[] mThumbIds;
public ImageAdapter(Context c)
{
mContext = c;
}
public int getCount() {
return mThumbIds.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 imageView;
if (convertView == null) {
imageView = new ImageView(mContext);
imageView.setLayoutParams(new GridView.LayoutParams(45, 45));
imageView.setAdjustViewBounds(false);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setPadding(8, 8, 8, 8);
} else {
imageView = (ImageView) convertView;
}
imageView
.setImageDrawable(LoadImageFromWebOperations("http://tmcrmappsqa.inservices.tatamotors.com/cordys/Images/mobile.png"+position));
return imageView;
}
protected Drawable LoadImageFromWebOperations(String url) {
try {
InputStream is = (InputStream) new URL(url).getContent();
Drawable d = Drawable.createFromStream(is, "src name");
return d;
} catch (Exception e) {
System.exit(0);
return null;
}
}
}