Question

我正在尝试在片段中创建自定义微调器。但是我无法创建它。创建spinner时会遇到以下错误.Plese帮助我解决这些错误。

java文件中的错误：

 1.The method getLayoutInflater(Bundle) in the type Fragment is not applicable for the arguments ()     GamesFragment.java  /dailyexpenses/src/com/example/dailyexpenses    line 47 Java Problem
 2.No enclosing instance of the type MainActivity is accessible in scope    GamesFragment.java  /dailyexpenses/src/com/example/dailyexpenses    line 31 Java Problem
 3.The constructor GamesFragment.MyAdapter(Context, int, String[]) refers to the missing type Context   GamesFragment.java  /dailyexpenses/src/com/example/dailyexpenses    line 31 Java Problem
 4.Context cannot be resolved to a type GamesFragment.java  /dailyexpenses/src/com/example/dailyexpenses    line 38 Java Problem

这是我的java文件

package com.example.dailyexpenses;
import java.util.ArrayList;
import java.util.List;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;  
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.Toast;
import android.widget.ImageView;
import android.widget.TextView;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.ViewGroup;

public class GamesFragment extends Fragment {
String[] Languages = { "Select a Language", "C# Language", "HTML Language",
        "XML Language", "PHP Language" };
        // Declaring the Integer Array with resourse Id's of Images for the Spinners
        Integer[] images = { 0, R.drawable.icon, R.drawable.petrol,
        R.drawable.books, R.drawable.recharge}; 
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {

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

    Spinner mySpinner = (Spinner) rootView.findViewById(R.id.spinner1);
    mySpinner.setAdapter(new MyAdapter(MainActivity.this, R.layout.custom,
            Languages));

    return rootView;
}
public class MyAdapter extends ArrayAdapter {

    public MyAdapter(Context context, int textViewResourceId,
    String[] objects) {
    super(context, textViewResourceId, objects);
    }

    public View getCustomView(int position, View convertView,
    ViewGroup parent) {

    // Inflating the layout for the custom Spinner
    LayoutInflater inflater = getLayoutInflater();
    View layout = inflater.inflate(R.layout.custom, parent, false);

    // Declaring and Typecasting the textview in the inflated layout
    TextView tvLanguage = (TextView) layout
    .findViewById(R.id.tvLanguage);

    // Setting the text using the array
    tvLanguage.setText(Languages[position]);

    // Setting the color of the text


    // Declaring and Typecasting the imageView in the inflated layout
    ImageView img = (ImageView) layout.findViewById(R.id.imgLanguage);

    // Setting an image using the id's in the array
    img.setImageResource(images[position]);

    // Setting Special atrributes for 1st element
    if (position == 0) {
    // Removing the image view
    img.setVisibility(View.GONE);
    // Setting the size of the text
    tvLanguage.setTextSize(20f);
    // Setting the text Color


    }

    return layout;
    }

    // It gets a View that displays in the drop down popup the data at the specified position
    @Override
    public View getDropDownView(int position, View convertView,
    ViewGroup parent) {
    return getCustomView(position, convertView, parent);
    }

    // It gets a View that displays the data at the specified position
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
    return getCustomView(position, convertView, parent);
    }
    }

    }

Answer 1

你需要在这里改变

  mySpinner.setAdapter(new MyAdapter(MainActivity.this, R.layout.custom,
        Languages));

到

  mySpinner.setAdapter(new MyAdapter(getActivity(), R.layout.custom,
        Languages));

您正在使用片段，因此Context将为getActivity()。

<强> 编辑：

在您的Adapter类中，如果您在膨胀自定义视图时未传递上下文的引用，则此行也需要更改。

 LayoutInflater inflater = getLayoutInflater();

到

 LayoutInflater inflater = getActivity().getLayoutInflater();

Answer 2

尝试更改此代码：

mySpinner.setAdapter(new MyAdapter(MainActivity.this, R.layout.custom,Languages));

有了这个：

mySpinner.setAdapter(new MyAdapter(getActivity(), R.layout.custom,Languages));

注意：使用getActivity（）中的活动上下文而不是片段中的static。

Answer 3

import android.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.Spinner;

public class My_Fragment extends Fragment
{
Spinner spinner;
String[] Languages = { "Select a Language", "C# Language", "HTML Language",
        "XML Language", "PHP Language" };
ArrayAdapter<String> adapter;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle savedInstanceState) 
{
    View view = inflater.inflate(R.layout.myfragment, null);
    spinner = (Spinner) view.findViewById(R.id.spinner);
    adapter = new ArrayAdapter<String>(getActivity(), R.layout.rowspinner,R.id.textView1 ,Languages);
    spinner.setAdapter(adapter);
    return view;
 }
}

 xml file 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" 
android:background="#345678">

<Spinner
    android:id="@+id/spinner"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

   </LinearLayout>



  row spnieer
 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
  xmlns:ads="http://schemas.android.com/apk/res-auto"
  android:layout_width="fill_parent"
  android:layout_height="fill_parent"
  android:orientation="vertical" >

  <LinearLayout
    android:layout_width="match_parent"
    android:layout_height="100dp"
    android:orientation="horizontal" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_weight="1"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:gravity="center"
            android:text="TextView"
            android:textSize="30dp" />
    </LinearLayout>
</LinearLayout>

值得注意的是在片段中创建微调器

3 个答案: