列表项在android自定义列表视图中重复

Question

在我的自定义列表视图中，项目是重复的。项目的位置对于所有项目都是相同的。 代码如下

ListAdapter.java-

    public class ListAdapter extends BaseAdapter{

    private List<String> mName;
private List<Drawable> mIcon;
private Context mContext;

public ListAdapter(Context mContext, List<String> Name, List<Drawable> Icon) {
    this.mContext=mContext;
    this.mName=Name;
    this.mIcon=Icon;
}

@Override
public int getCount() {
    // TODO Auto-generated method stub
    return mName.size();
}

@Override
public Object getItem(int position) {
    // TODO Auto-generated method stub
    return position;
}

@Override
public long getItemId(int position) {
    // TODO Auto-generated method stub
    return position;
}

@Override
public View getView(final int position, View v, ViewGroup parent) {

    View mLayout;
    TextView mText;
    ImageView mImage;
    CheckBox mCheckBox;

    if(v==null){
        LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
        mLayout=new View(mContext);
        mLayout=(LinearLayout) inflater.inflate(R.layout.list_menu, null);

        mText=(TextView) mLayout.findViewById(R.id.Name);
        mImage=(ImageView) mLayout.findViewById(R.id.Icon);
        mCheckBox=(CheckBox) mLayout.findViewById(R.id.mCheckbox);

        mText.setText(mName.get(position));
        mImage.setImageDrawable(mIcon.get(position));

        mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {

            @Override
            public void onCheckedChanged(CompoundButton check, boolean isChecked) {
                if(check.isChecked()){
                    Toast.makeText(mContext, "..."+mName.get(position)+"..."+position, Toast.LENGTH_SHORT).show();
                }
            }
        });
    }   
    else{
        mLayout=(View)v;
    }
    return mLayout;
}

  }

Answer 1

试试这个，每个转换视图都需要setTag()。

 @Override
public View getView(final int position, View convertView, ViewGroup parent) {
    final ViewHolder mHolder;
    if (convertView == null) {
        convertView = mInflater.inflate(R.layout.list_menu, null);
        mHolder = new ViewHolder();

        mHolder.mText=(TextView) convertView.findViewById(R.id.appName);
        mHolder.mImage=(ImageView) convertView.findViewById(R.id.appIcon);
        mHolder.mCheckBox=(CheckBox) convertView.findViewById(R.id.mCheckbox);

        convertView.setTag(mHolder);

    } else {
        mHolder = (ViewHolder) convertView.getTag();
    }

    return convertView;
}

private class ViewHolder {
    private TextView mText;
    private ImageView mImage;
    private CheckBox mCheckBox;

}

Answer 2

改变你的getView

 LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    mLayout=new View(mContext);
    mLayout=(LinearLayout) inflater.inflate(R.layout.list_menu, null);

在您的构造函数中初始化充气机。删除此 mLayout=new View(mContext) 因为您正在使用 mLayout=(LinearLayout) inflater.inflate(R.layout.list_menu, null) 扩展布局

在你的构造函数中

LayoutInflater inflater;
public ListAdapter(Context mContext, List<String> Name, List<Drawable> Icon) {
this.inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
this.mContext=mContext;
this.mName=Name;
this.mIcon=Icon;
}

使用 View holder 来实现平滑滚动和性能。

http://developer.android.com/training/improving-layouts/smooth-scrolling.html

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

    ViewHolder vh;
    if(convertView==null){
        vh = new ViewHolder();
        convertView =(LinearLayout) inflater.inflate(R.layout.list_menu, null);

        vh.mText=(TextView) convertView.findViewById(R.id.Name);
        vh.mImage=(ImageView) convertView.findViewById(R.id.Icon);
        vh.mCheckBox=(CheckBox) convertView.findViewById(R.id.mCheckbox);

        convertView.setTag(vh); 
    } else { 
        vh = (ViewHolder) convertView.getTag(); 
    } 

    vh.mText.setText(mName.get(position));
    vh.mImage.setImageDrawable(mIcon.get(position));
    vh.mCheckBox.setOnCheckedChangeListener(new OnCheckedChangeListener() {

        @Override
        public void onCheckedChanged(CompoundButton check, boolean isChecked) {
            if(check.isChecked()){
                Toast.makeText(mContext, "..."+mName.get(position)+"..."+position, Toast.LENGTH_SHORT).show();
            }
        }
    });
    return convertView;
}

static class ViewHolder
{
    TextView mText;
    ImageView mImage;
    CheckBox mCheckBox;
}

Answer 3

// try this
 public class ListAdapter extends BaseAdapter {

        private List<String> mName;
        private List<Drawable> mIcon;
        private Context mContext;

        public ListAdapter(Context mContext, List<String> Name, List<Drawable> Icon) {
            this.mContext=mContext;
            this.mName=Name;
            this.mIcon=Icon;
        }

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return mName.size();
        }

        @Override
        public Object getItem(int position) {
            // TODO Auto-generated method stub
            return position;
        }

        @Override
        public long getItemId(int position) {
            // TODO Auto-generated method stub
            return position;
        }

        @Override
        public View getView(final int position, View v, ViewGroup parent) {

            ViewHolder holder;

            if(v==null){
                holder = new ViewHolder();
                LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
                v =(LinearLayout) inflater.inflate(R.layout.list_menu, null);

                holder.mText=(TextView) v.findViewById(R.id.Name);
                holder.mImage=(ImageView) v.findViewById(R.id.Icon);
                holder.mCheckBox=(CheckBox) v.findViewById(R.id.mCheckbox);

              v.setTag(holder);
            }
            else{
               holder = (ViewHolder) v.getTag();
            }
            holder.mText.setText(mName.get(position));
            holder.mImage.setImageDrawable(mIcon.get(position));

            holder.mCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

                @Override
                public void onCheckedChanged(CompoundButton check, boolean isChecked) {
                    if(check.isChecked()){
                        Toast.makeText(mContext, "..."+mName.get(position)+"..."+position, Toast.LENGTH_SHORT).show();
                    }
                }
            });
            v.setTag(holder);
            return v;
        }

         class ViewHolder{
            TextView mText;
            ImageView mImage;
            CheckBox mCheckBox;
        }

    }

Answer 4

确保 convertView 不为空。因此将所有代码放在 if(convertView == null){ 之后 } 这确保你有一个值不为 null 的 convertView，如果是的话，通过从上下文中膨胀。

@Override
public View getView(final int position, View convertView, ViewGroup parent) {

  if (convertView == null) {
    LayoutInflater inflater = LayoutInflater.from(context);
    convertView = inflater.inflate(R.layout.list_menu, parent, false);
  } 

  TextView mText=(TextView) convertView.findViewById(R.id.appName);
  ImageView mImage=(ImageView) convertView.findViewById(R.id.appIcon);
  CheckBox mCheckBox=(CheckBox) convertView.findViewById(R.id.mCheckbox);

  mText.setText(mName.get(position));
  mImage.setImageDrawable(mIcon.get(position));

  return convertView;
}