Question

所以我在FinderActivity.class中执行适配器时遇到此错误。

public class FinderActivity extends ListActivity
{
    private List<String> itemsearchoptions = Arrays.asList(
            new String[]
                    {
                        "Search Service Center","Search Showroom",
                        "Area Surveillance", "Nearest OAC Offices"
                    });
    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.finder);


        getListView().setAdapter(new FinderListAdapter(this, this.itemsearchoptions));//cause of error


    }

这是My FinderAdapterclass：

public class FinderListAdapter extends BaseAdapter
{
    Context context;
    LayoutInflater inflater;
    private int[]icons = 
    {
        R.drawable.icon_service_center,
        R.drawable.icon_car_showroom, 
        R.drawable.icon_radar, 
        R.drawable.icon_office
    };
    private List<String>options = null;

    public FinderListAdapter(Context paramContext, List<String>paramList)
    {
        this.context = paramContext;
        this.options = paramList;
        this.inflater = LayoutInflater.from(paramContext);
    }

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

    @Override
    public Object getItem(int paramInt) 
    {
        return this.options.get(paramInt);
    }

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


    @Override
    public View getView(int paramInt, View paramView, ViewGroup paramViewGroup) 
    {
        String str = (String)this.options.get(paramInt);

        if(paramView == null)
        {

        }
        else
        {

            return paramView;
        }
        return paramViewGroup;
    }
    public boolean isEmpty()
    {
        return (this.options == null)||(this.options.size()==0);
    }

    private static class ViewHolder
    {
        ImageView finderIcon;
        TextView finderText;
    }
}

我在项目列表中使用了LinearLayout

我已经阅读了几个关于这个错误的类似问题，但还没有完全理解这个概念。所以任何帮助将不胜感激。感谢

编辑：抱歉忘了堆栈跟踪

07-08 15:31:42.380: E/AndroidRuntime(4550): FATAL EXCEPTION: main
07-08 15:31:42.380: E/AndroidRuntime(4550): java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.widget.AbsListView$LayoutParams
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.ListView.measureScrapChild(ListView.java:1166)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.ListView.measureHeightOfChildren(ListView.java:1248)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.ListView.onMeasure(ListView.java:1158)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.View.measure(View.java:15525)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1404)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.LinearLayout.measureVertical(LinearLayout.java:695)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.LinearLayout.onMeasure(LinearLayout.java:588)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.View.measure(View.java:15525)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.widget.FrameLayout.onMeasure(FrameLayout.java:310)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.View.measure(View.java:15525)
07-08 15:31:42.380: E/AndroidRuntime(4550):     at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4825)

Answer 1

在导入中使用android.widget.AbsListView.LayoutParams代替android.widget.LinearLayout.LayoutParams。

ClassCastException栈跟踪非常具有描述性......

Answer 2

对于其他有同样问题的人。请首先修复你的getView方法。

尝试这样做。

public View getView(int i, View view, ViewGroup viewGroup) {
    LayoutInflater layoutInflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

    View root;

    if(view == null){
       root = layoutInflater.inflate(R.layout.yourLayout, null);
    } else {
       root = view;
    }

    return root;
    }

这可以解决android.widget.LinearLayout$LayoutParams cannot be cast to android.widget.AbsListView$LayoutParams错误。

相信我，我只是面对这个确切的问题，但我设法以这种方式解决它。

ClassCastException：android.widget.LinearLayout $ LayoutParams

2 个答案: