使用 Fragment Android 创建简单的 listView

Posted 2023-04-19

【中文标题】使用 Fragment Android 创建简单的 listView

【英文标题】：Create simple listView using Fragment Android

【发布时间】：2015-04-12 02:13:23

【问题描述】：

我是 listView 的新手，搜索了很多教程，但很困惑，因为教程教的是不同的风格，而且很复杂。基本上我想在按收藏选项卡时创建一个带有图像和文本的列表视图。

我唯一感到困惑的是 FavouriteFragment.java 的编码，因为我不确定它是否正确。 listView 没有出现。希望任何人都可以帮助我。

这是我的 activity_favourite_fragment.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_
android:layout_
android:background="#5ba4e5"
android:orientation="vertical" >

<TextView
    android:id="@+id/textview"
    android:layout_
    android:layout_ />

<ListView
    android:id="@+id/listview"
    android:layout_
    android:layout_ />

</LinearLayout>

这是我的 single_row.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_
android:layout_
android:padding="5dp" >

<ImageView
    android:id="@+id/icon"
    android:layout_
    android:layout_
    android:layout_marginLeft="5px"
    android:layout_marginRight="30px"
    android:layout_marginTop="5px"
    android:layout_weight="0.68"
    android:src="@drawable/ic_launcher" >

</ImageView>

<TextView
    android:id="@+id/label"
    android:layout_
    android:layout_
    android:layout_weight="2"
    android:layout_gravity="center"
    android:text="@+id/label"
    android:textSize="30px" />

</LinearLayout>    

MainActivity.java

import android.app.ActionBar;
import android.content.Intent;
import android.app.ActionBar.Tab;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import com.example.sgrecipe.TabsAdapter;

public class MainActivity extends FragmentActivity implements
    ActionBar.TabListener 

private ViewPager viewPager;
private TabsAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs =  "Recipes", "Favourites", "Quiz" ;

@Override
protected void onCreate(Bundle savedInstanceState) 
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    // Initilization
    viewPager = (ViewPager) findViewById(R.id.pager);
    actionBar = getActionBar();
    mAdapter = new TabsAdapter(getSupportFragmentManager());

    viewPager.setAdapter(mAdapter);
    actionBar.setHomeButtonEnabled(false);
    actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);

    // Adding Tabs
    for (String tab_name : tabs) 
        actionBar.addTab(actionBar.newTab().setText(tab_name)
                .setTabListener(this));
    

    /**
     * on swiping the viewpager make respective tab selected
     * */
    viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() 

        @Override
        public void onPageSelected(int position) 
            // on changing the page
            // make respected tab selected
            actionBar.setSelectedNavigationItem(position);
        

        @Override
        public void onPageScrolled(int arg0, float arg1, int arg2) 
        

        @Override
        public void onPageScrollStateChanged(int arg0) 
        
    );


@Override
public void onTabReselected(Tab tab, FragmentTransaction ft) 


@Override
public void onTabSelected(Tab tab, FragmentTransaction ft) 
    // on tab selected
    // show respected fragment view
    viewPager.setCurrentItem(tab.getPosition());


@Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) 


// insert option menu
@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;

FavouriteFragment.java

import com.example.sgrecipe.MobileArrayAdapter;
import android.app.Fragment;
import android.app.ListActivity;
import android.app.ListFragment;
import android.os.Bundle;
import android.widget.ListView;
import android.widget.Toast;
import android.text.Layout;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class FavouriteFragment extends Fragment

String[] Recipe = new String[]  "Chinese Food", "Malay Food", "Indian        Food", "Others";
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,Bundle    savedInstanceState) 
    super.onCreate(savedInstanceState);
    ViewGroup root = (ViewGroup) inflater.inflate(R.layout.activity_favourite_fragment, null);

    MobileArrayAdapter adapter = new MobileArrayAdapter(this.getActivity(), Recipe);
    ListView listView = (ListView) getActivity().findViewById(R.id.listview);

    listView.setAdapter(adapter);

    return root;

MobileArrayAdapter.java

import com.example.sgrecipe.R;
import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageView;
import android.widget.TextView;

public class MobileArrayAdapter extends ArrayAdapter<String> 
private final Context context;
private final String[] values;

public MobileArrayAdapter(Context context, String[] values) 
    super(context, R.layout.single_row, values);
    this.context = context;
    this.values = values;


@Override
public View getView(int position, View convertView, ViewGroup parent) 
    LayoutInflater inflater = (LayoutInflater) context
            .getSystemService(Context.LAYOUT_INFLATER_SERVICE);
    View rowView = inflater.inflate(R.layout.single_row,
            parent, false);
    TextView textView = (TextView) rowView.findViewById(R.id.label);
    ImageView imageView = (ImageView) rowView.findViewById(R.id.icon);
    textView.setText(values[position]);
    // Change icon based on name
    String s = values[position];
    System.out.println(s);
    if (s.equals("Chinese Food")) 
        imageView.setImageResource(R.drawable.chinese);
     else if (s.equals("Malay Food")) 
        imageView.setImageResource(R.drawable.malay);
     else if (s.equals("Indian Food")) 
        imageView.setImageResource(R.drawable.indian);
     else 
        imageView.setImageResource(R.drawable.others);
    
    return rowView;

【问题讨论】：

能不能也贴一下MobileArrayAdapter的代码

刚刚上传了mobileArrayAdapter.java

【参考方案1】：

您的问题是如何检索ListView，只需修改此行：

ListView listView = (ListView) getActivity().findViewById(R.id.listview);

看起来像这样：

ListView listView = (ListView) root.findViewById(R.id.listview);

列表视图是片段根视图的一部分，因此需要在该视图中找到它，而不是在您的 MainActivity 中

【讨论】：

但是TabsAdapter还有另一个问题。案例 1：返回新的 FavouriteFragment()；它说该类型不能从 FavouriteFragment 转换为 Fragment

FavouriteFragment 需要扩展 android.support.v4.app.Fragment