使用＆QUOT Android的背景下，这＆QUOT;阶级不是一个活动 [英] Android context using "this" on class that is not an activity

问题描述

我创建了下面的类来填充的ListView 有两种不同的看法。其中两种含有的是包含在捆绑一个微调，而我试图用的ArrayList 来填充（每个微调）。我处理的问题是 ArrayAdapter 的构造函数，这显然与我使用的上下文（本）中的问题。任何想法？

 公共类InsertAdapter延伸BaseAdapter {私有静态最终诠释OWN_KEY = 0;
私有静态最终诠释FOREIGN_KEY = 1;
私人的ArrayList＆LT; ColumnProperties＆GT;列=新的ArrayList＆LT; ColumnProperties＆GT;（）;
私人捆绑spinner_strings;@覆盖
公众诠释getViewTypeCount（）{
    返回2;
}@覆盖
公众诠释getItemViewType（INT位置）{
    返回（columns.get（位置）.isForeign（））？ FOREIGN_KEY：OWN_KEY;
}@覆盖
公众诠释的getCount（）{
    返回columns.size（）;
}@覆盖
公共对象的getItem（INT位置）{
    返回的getItem（位置）;
}@覆盖
众长getItemId（INT位置）{
    返回的位置;
}公共查看getView（INT位置，查看视图的ViewGroup父）{
    整型= getItemViewType（位置）;
    如果（查看== NULL）{
        LayoutInflater气筒=
                LayoutInflater.from（parent.getContext（））;
        如果（类型== 0）{
            鉴于= inflater.inflate（
                    R.layout.text_field，父母，假）;
        }其他{
            鉴于= inflater.inflate（
                    R.layout.text_spinner，父母，假）;
        }
    }    ColumnProperties柱= columns.get（位置）;    TextView的COL_NAME =（TextView中）view.findViewById（R.id.column_name）;
    col_name.setText（column.getName（））;    如果（类型== FOREIGN_KEY）{
        微调微调=（微调）view.findViewById（R.id.foreign_keys）;
        ArrayList的＆LT;串GT; spinner_list = spinner_strings.getStringArrayList（column.getName（））;
        //列表＆LT;串GT;清单;        ArrayAdapter spinner_adapter =新ArrayAdapter（这一点，android.R.layout.simple_spinner_item，spinner_list）;
        spinner_adapter.setDropDownViewResource（android.R.layout.simple_spinner_dropdown_item）;        spinner.setAdapter（spinner_adapter）;
    }    返回视图。
}公共无效getSpinnerStrings（捆绑spinner_strings）{
    this.spinner_strings = spinner_strings;
}}
 

解决方案

@ρяσѕρєяķ写道：

  

使用 view.getContext（）或 parent.getContext（）而不是这

I created the following class to populate a listView with two different kinds of views. One of the two kinds contain is a spinner, which I'm trying to populate with Arraylists (one for each spinner) contained in the bundle. The problem I'm dealing with is the ArrayAdapter constructor, which clearly has a problem with the context I'm using ("this"). Any ideas?

public class InsertAdapter extends BaseAdapter {

private static final int OWN_KEY = 0;
private static final int FOREIGN_KEY = 1;
private ArrayList<ColumnProperties> columns = new ArrayList<ColumnProperties>();
private Bundle spinner_strings;

@Override
public int getViewTypeCount() {
    return 2;
}

@Override
public int getItemViewType(int position){
    return (columns.get(position).isForeign()) ? FOREIGN_KEY : OWN_KEY;
}

@Override
public int getCount() {
    return columns.size();
}

@Override
public Object getItem(int position) {
    return getItem(position);
}

@Override
public long getItemId(int position) {
    return position;
}

public View getView(int position, View view, ViewGroup parent) {
    int type = getItemViewType(position);
    if (view == null) {
        LayoutInflater inflater =
                LayoutInflater.from(parent.getContext());
        if(type==0) {
            view = inflater.inflate(
                    R.layout.text_field, parent, false);
        }else{
            view = inflater.inflate(
                    R.layout.text_spinner, parent, false);
        }
    }

    ColumnProperties column = columns.get(position);

    TextView col_name = (TextView) view.findViewById(R.id.column_name);
    col_name.setText(column.getName());

    if(type==FOREIGN_KEY){
        Spinner spinner = (Spinner) view.findViewById(R.id.foreign_keys);
        ArrayList<String> spinner_list = spinner_strings.getStringArrayList(column.getName());
        //List<String> list;

        ArrayAdapter spinner_adapter = new ArrayAdapter(this , android.R.layout.simple_spinner_item,spinner_list);
        spinner_adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);

        spinner.setAdapter(spinner_adapter);
    }

    return view;
}

public void getSpinnerStrings(Bundle spinner_strings){
    this.spinner_strings = spinner_strings;
}

}

解决方案

@ρяσѕρєя K wrote:

Use view.getContext() or parent.getContext() instead of this

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