为什么我得到一个构造函数未定义的错误？ [英] Why am I getting a Constructor Undefined error?

问题描述

这是为什么行：

  g.setAdapter（新ImageAdapter（本））;
 

给我的错误构造未​​定义？

我用这个指南，使标签 HTTP：// WWW。 androidbegin.com/tutorial/implementing-fragment-tabs-in-android/ ，现在我想要实现我的标签之一网格视图，但没有与ImageAdapter一个问题。如果我将鼠标放在错误，改变基于它说什么比它刚刚起步改变背景的东西，使更多的错误，code。

下面是code：

 包com.example.tabexample;进口android.app.Fragment;
进口android.content.Context;
进口android.os.Bundle;
进口android.view.LayoutInflater;
进口android.view.View;
进口android.view.ViewGroup;
进口android.widget.BaseAdapter;
进口android.widget.GridView;
进口android.widget.ImageView;公共类FragmentTab2扩展片段{
@覆盖
公共查看onCreateView（LayoutInflater充气器，容器的ViewGroup，
        捆绑savedInstanceState）{
    查看rootView = inflater.inflate（R.layout.fragment2，集装箱，FALSE）;
    GridView控件G =（GridView控件）rootView.findViewById（R.id.grid_view）;
    g.setAdapter（新ImageAdapter（本））;
    返回rootView;}
公共类ImageAdapter延伸BaseAdapter {
    私人上下文的背景下;
    公共整数[] =皮肤{R.drawable.s1，R.drawable.s2，R.drawable.s3，
            R.drawable.s4，R.drawable.s5，R.drawable.s6，
            R.drawable.s7，R.drawable.s8，R.drawable.s9，
            R.drawable.s10，R.drawable.s11，R.drawable.s12};    公共ImageAdapter（上下文C）{
        // TODO自动生成构造函数存根
        上下文= C;
    }    @覆盖
    公众诠释的getCount（）{
        // TODO自动生成方法存根
        返回0;
    }    @覆盖
    公共对象的getItem（INT位置）{
        // TODO自动生成方法存根
        返回null;
    }    @覆盖
    众长getItemId（INT位置）{
        // TODO自动生成方法存根
        返回0;
    }    @覆盖
    公共查看getView（INT位置，查看convertView，父母的ViewGroup）{
        // TODO自动生成方法存根
        ImageView的PIC =新ImageView的（上下文）;
        pic.setLayoutParams（新GridView.LayoutParams（200,200））;
        pic.setScaleType（ImageView.ScaleType.FIT_CENTER）;
        pic.setPadding（8,8，8,8）;
        pic.setImageResource（皮肤[位置]）;
        返回图片;
    }}}
 

解决方案

替换该行以

  g.setAdapter（新ImageAdapter（getActivity（）））;
 

片段不会从上下文继承。

Why is this line:

g.setAdapter(new ImageAdapter(this));  

giving me the error "Constructor Undefined"?

I used this guide to make tabs http://www.androidbegin.com/tutorial/implementing-fragment-tabs-in-android/ and now I'm trying to implement a grid view on one of my tabs but there is a problem with the ImageAdapter. If I mouse over the error and change the code based on what it says than it just starts changing the "Context" stuff and making more errors.

Here is the code:

package com.example.tabexample;

import android.app.Fragment;
import android.content.Context;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class FragmentTab2 extends Fragment {
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    View rootView = inflater.inflate(R.layout.fragment2, container, false);


    GridView g = (GridView) rootView.findViewById(R.id.grid_view);
    g.setAdapter(new ImageAdapter(this));


    return rootView;

}
public class ImageAdapter extends BaseAdapter{
    private Context context;
    public Integer[] Skins = {R.drawable.s1, R.drawable.s2, R.drawable.s3,
            R.drawable.s4, R.drawable.s5, R.drawable.s6,
            R.drawable.s7, R.drawable.s8, R.drawable.s9,
            R.drawable.s10, R.drawable.s11, R.drawable.s12};

    public ImageAdapter(Context c) {
        // TODO Auto-generated constructor stub
        context = c;
    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return 0;
    }

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

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return 0;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        ImageView pic = new ImageView(context);
        pic.setLayoutParams(new GridView.LayoutParams(200,200));
        pic.setScaleType(ImageView.ScaleType.FIT_CENTER);
        pic.setPadding(8, 8, 8, 8);
        pic.setImageResource(Skins[position]);
        return pic;
    }

}

}

解决方案

Replace that line with

g.setAdapter(new ImageAdapter(getActivity()));

Fragment doesn't inherit from Context.

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