Question

我目前有片段活动，但我无法让我的适配器正常工作。在我的片段活动中，我在setAdapter行上有错误。这是我的片段：

package com.oneapp.tiradentes;

import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ListView;

import java.util.ArrayList;

public class FragmentA extends Fragment {

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {

    View rootView=inflater.inflate(R.layout.activity_main4,container,false);

    ArrayList<Carro> carros = new ArrayList<Carro>();

    for(int i = 0; i < 5; i++){

        Carro carro = new Carro();
        carro.setModelo("Carro "+(i + 1));
        carro.setMarca("Marca "+(i + 1));

        carros.add(carro);
    }

    ListView lv = (ListView) getView().findViewById(R.id.lv);
    lv.setAdapter(new CarroAdapter(this, carros));

    return rootView;
}
}

在这一行显示错误：

lv.setAdapter(new CarroAdapter(this, carros));

请有人可以帮助我吗？

我的适配器：包com.oneapp.tiradentes;

import java.util.ArrayList;

import android.content.Context;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class CarroAdapter extends BaseAdapter {
private Context context;
private ArrayList<Carro> lista;

public CarroAdapter(Context context, ArrayList<Carro> lista){
    this.context = context;
    this.lista = lista;
}



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

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

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

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

    Carro carro = lista.get(position);
    View layout;

    if(convertView == null){
LayoutInflater inflater =   (LayoutInflater)  context.getSystemService                  

(Context.LAYOUT_INFLATER_SERVICE); 
layout = inflater.inflate(R.layout.carros, null);
    }
    else{
        layout = convertView;
    }


    TextView modelo = (TextView) layout.findViewById(R.id.t1);
    modelo.setText(carro.getModelo());

    TextView marca = (TextView) layout.findViewById(R.id.t2);
    marca.setText(carro.getMarca());

    ImageView iv = (ImageView) layout.findViewById(R.id.iv);
    iv.setImageResource(carro.getCarroImagem(position));

    if(position % 2 == 0){
        layout.setBackgroundColor(Color.YELLOW);
    }

    return layout;
}

}

错误：

carroAdapter (android.content.Context,       ArrayList<Carro>) in               

CarroAdapter cannot be applied to (com.oneapp.tiradentes.FragmentA ,   

ArrayList<Carro>)

Answer 1

而不是：

ListView lv = (ListView) getView().findViewById(R.id.lv);

尝试使用：

ListView lv = (ListView) rootView.findViewById(R.id.lv);

因为getView()将在方法onCreateView

之后就绪

Answer 2

您的CarroAdapter将上下文作为第一个参数，并且您正在从片段类发送this，这意味着您正在发送FragmentA实例。将其更改为

lv.setAdapter(new CarroAdapter(getActivity(), carros));

同时尽量避免将Context作为成员保留，只在

中使用上下文的适配器中

 LayoutInflater inflater =   (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);

你可以用

代替

 LayoutInflater inflater = (LayoutInflater) parent.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);

Answer 3

在这个地方修改代码：

Utils.LogDebug("Email File Thread took " + timer.ElapsedMilliseconds.ToString() + "(ms)");

这是因为片段不包含任何上下文;你必须在这里传递活动。

setAdapter不适用于Fragment

3 个答案: