2014-09-21 40 views
0

我有一個列表視圖,顯示整個星期的天氣預報。我也在這個ListView上設置了一個適配器mForecastAdapter。但是,當我預覽fragment_main.xml文件,我得到的是預覽ArrayAdapter不按預期工作

Fragment

這是我在MainActivity.java

package com.example.android.sunshine.app; 

import android.os.Bundle; 
import android.support.v4.app.Fragment; 
import android.support.v7.app.ActionBarActivity; 
import android.view.LayoutInflater; 
import android.view.Menu; 
import android.view.MenuItem; 
import android.view.View; 
import android.view.ViewGroup; 
import android.widget.ArrayAdapter; 
import android.widget.ListView; 

import java.util.ArrayList; 
import java.util.Arrays; 
import java.util.List; 


public class MainActivity extends ActionBarActivity { 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_main); 
    if (savedInstanceState == null) { 
     getSupportFragmentManager().beginTransaction() 
       .add(R.id.container, new PlaceholderFragment()) 
       .commit(); 
    } 
} 


@Override 
public boolean onCreateOptionsMenu(Menu menu) { 
    // Inflate the menu; this adds items to the action bar if it is present. 
    getMenuInflater().inflate(R.menu.main, menu); 
    return true; 
} 

@Override 
public boolean onOptionsItemSelected(MenuItem item) { 
    // Handle action bar item clicks here. The action bar will 
    // automatically handle clicks on the Home/Up button, so long 
    // as you specify a parent activity in AndroidManifest.xml. 
    int id = item.getItemId(); 
    if (id == R.id.action_settings) { 
     return true; 
    } 
    return super.onOptionsItemSelected(item); 
} 

/** 
* A placeholder fragment containing a simple view. 
*/ 
public static class PlaceholderFragment extends Fragment { 

    public PlaceholderFragment() { 
    } 

    @Override 
    public View onCreateView(LayoutInflater inflater, ViewGroup container, 
      Bundle savedInstanceState) { 
     View rootView = inflater.inflate(R.layout.fragment_main, container, false); 
     String[] forecastArray = { 
       "Today - Sunny - 88/64", 
       "Tomorrow - Rainy - 73/54", 
       "Wednesday - Snow - 63/54", 
       "Thursday - Rainy - 83/54", 
       "Friday - Rainy - 73/58", 
       "Saturday - Gloomy - 64/54", 
       "Sunday - Rainy - 73/64" 
     }; 
     ArrayAdapter<String> mForecastAdapter; 
     List<String> weekForecast = new ArrayList<String>(Arrays.asList(forecastArray)); 
     mForecastAdapter = new ArrayAdapter<String>(getActivity(), R.layout.list_item_forecast, R.id.list_item_forecast_textview, weekForecast); 
     ListView listView = (ListView) rootView.findViewById(R.id.listview_forecast); 
     listView.setAdapter(mForecastAdapter); 
     return rootView; 
    } 
} 

}代碼 什麼是錯的一個ArrayAdapter?如果這有什麼不同,我正在使用Android Studio。

+1

什麼是你的問題?你期望佈局看起來像什麼? – erad 2014-09-21 11:39:33

回答

2

在佈局預覽中,默認情況下,ListView將通過顯示包含「Item 1」,「Item 2」,「Item 3」等的默認ListView顯示類似於上面的列表。 。和「子項目1」,「子項2」,「子選項3」,等等。

你不會看到實際的ListView(假設你做了正確的編碼),直到你運行你的應用程序在實際的裝置上的仿真器或測試。