NullPointerException:尝试调用虚拟方法';intandroid.graphics.Bitmap.getWidth()'; 公共类CategoryAdapter扩展了BaseAdapter{ 语境; ArrayList模型; LayoutInflater LayoutInflater; 公共类别适配器(活动,ArrayList模型){ this.model=模型; 这个上下文=活动; } @凌驾 public int getCount(){ 返回model.size(); } @凌驾 公共对象getItem(int位置){ 返回null; } @凌驾 公共长getItemId(int位置){ 返回位置; } @凌驾 公共视图getView(int位置、视图转换视图、视图组父视图){ ViewHolder ViewHolder=null; layoutInflater=(layoutInflater)context.getSystemService(context.LAYOUT\u INFLATER\u SERVICE); if(convertView==null){ viewHolder=新的viewHolder(); convertView=LayoutFlater.充气(R.layout.category_适配器,父级,false); viewHolder.imageView=(imageView)convertView.findViewById(R.id.category\u grid\u image); viewHolder.textView=(textView)convertView.findViewById(R.id.get\u category\u title); convertView.setTag(viewHolder); }否则{ viewHolder=(viewHolder)convertView.getTag(); } viewHolder.textView.setText(model.get(position.getCategoryName()); 如果(位置
错误跟踪显示错误发生在NullPointerException:尝试调用虚拟方法';intandroid.graphics.Bitmap.getWidth()'; 公共类CategoryAdapter扩展了BaseAdapter{ 语境; ArrayList模型; LayoutInflater LayoutInflater; 公共类别适配器(活动,ArrayList模型){ this.model=模型; 这个上下文=活动; } @凌驾 public int getCount(){ 返回model.size(); } @凌驾 公共对象getItem(int位置){ 返回null; } @凌驾 公共长getItemId(int位置){ 返回位置; } @凌驾 公共视图getView(int位置、视图转换视图、视图组父视图){ ViewHolder ViewHolder=null; layoutInflater=(layoutInflater)context.getSystemService(context.LAYOUT\u INFLATER\u SERVICE); if(convertView==null){ viewHolder=新的viewHolder(); convertView=LayoutFlater.充气(R.layout.category_适配器,父级,false); viewHolder.imageView=(imageView)convertView.findViewById(R.id.category\u grid\u image); viewHolder.textView=(textView)convertView.findViewById(R.id.get\u category\u title); convertView.setTag(viewHolder); }否则{ viewHolder=(viewHolder)convertView.getTag(); } viewHolder.textView.setText(model.get(position.getCategoryName()); 如果(位置,android,exception,bitmap,Android,Exception,Bitmap,错误跟踪显示错误发生在 public class CategoryAdapter extends BaseAdapter { Context context; ArrayList<ModelCategory> model; LayoutInflater layoutInflater; public CategoryAdapter(Activity activity, ArrayList<ModelCategory> model) { this.model = m
public class CategoryAdapter extends BaseAdapter {
Context context;
ArrayList<ModelCategory> model;
LayoutInflater layoutInflater;
public CategoryAdapter(Activity activity, ArrayList<ModelCategory> model) {
this.model = model;
this.context = activity;
}
@Override
public int getCount() {
return model.size();
}
@Override
public Object getItem(int position) {
return null;
}
@Override
public long getItemId(int position) {
return position;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = null;
layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
if (convertView == null) {
viewHolder = new ViewHolder();
convertView = layoutInflater.inflate(R.layout.category_adapter, parent, false);
viewHolder.imageView = (ImageView) convertView.findViewById(R.id.category_grid_image);
viewHolder.textView = (TextView) convertView.findViewById(R.id.get_category_title);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
viewHolder.textView.setText(model.get(position).getCategoryName());
if(position<=3){
viewHolder.imageView.setImageBitmap(StringToBitMap(model.get(position).getCategoryImage()));
}
else {
viewHolder.imageView.setImageBitmap(getBitmap(model.get(position).getCategoryImage()));
}
return convertView;
}
private class ViewHolder {
public ImageView imageView;
public TextView textView;
}
private Bitmap getBitmap(String path) {
BitmapFactory.Options option = new BitmapFactory.Options();
option.inSampleSize = 8;
Bitmap bitmap = BitmapFactory.decodeFile(path, option);
Matrix matrix = new Matrix();
matrix.postRotate(getImageOrientation(path));
Bitmap rotatedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
Bitmap resized = Bitmap.createScaledBitmap(rotatedBitmap, 150, 150, true);
return resized;
}
private static int getImageOrientation(String imagePath) {
int rotate = 0;
try {
File imageFile = new File(imagePath);
ExifInterface exif = new ExifInterface(
imageFile.getAbsolutePath());
int orientation = exif.getAttributeInt(
ExifInterface.TAG_ORIENTATION,
ExifInterface.ORIENTATION_NORMAL);
switch (orientation) {
case ExifInterface.ORIENTATION_ROTATE_270:
rotate = 270;
break;
case ExifInterface.ORIENTATION_ROTATE_180:
rotate = 180;
break;
case ExifInterface.ORIENTATION_ROTATE_90:
rotate = 90;
break;
}
} catch (IOException e) {
e.printStackTrace();
}
return rotate;
}
public Bitmap StringToBitMap(String encodedString){
try {
byte [] encodeByte=Base64.decode(encodedString, Base64.DEFAULT);
Bitmap bitmap=BitmapFactory.decodeByteArray(encodeByte, 0, encodeByte.length);
return bitmap;
} catch(Exception e) {
e.getMessage();
return null;
}
}
作为公共静态位图解码文件(字符串路径名,选项选项)
方法的文档:
Bitmap bitmap = BitmapFactory.decodeFile(path, option);
Bitmap rotatedBitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, true);
如果图像数据无法解码,此方法将返回null。请注意类似
E/BitmapFactory:无法解码流:…
的日志,以找出此方法失败的原因。可能是您提供了错误的路径。我的问题是,我在后台线程中调用了“decodeFile”,返回null。将该代码移动到主线程修复了该问题。您的位图创建似乎失败。是否确定路径
值正确并指向实际位图?再次检查getBitmap方法,您将获得空指针。
return The decoded bitmap, or null if the image data could not be
decoded, or, if opts is non-null, if opts requested only the
size be returned (in opts.outWidth and opts.outHeight)