Android ListView 与片段中的图像和文本答案

【问题标题】：Android ListView with images and text in FragmentAndroid ListView 与片段中的图像和文本
【发布时间】：2016-05-11 13:45:21
【问题描述】：

我在 Android Studio 中创建了一个导航抽屉。在导航抽屉的片段中，我想添加一个带有图像和文本的 ListView。但是在我运行程序并单击片段程序崩溃并显示文本“不幸的是，SerialMania 已停止”之后。我做错了什么？

package boiko.taisiia.com.serialmania;

import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;


import android.widget.SimpleAdapter;

public class Date extends Fragment {

// Array of strings storing country names
String[] countries = new String[] {
        "India",
        "Pakistan",
        "Sri Lanka",
        "China",
        "Bangladesh",
        "Nepal",
        "Afghanistan",
        "North Korea",
        "South Korea",
        "Japan"
};

// Array of integers points to images stored in /res/drawable-ldpi/
int[] flags = new int[]{
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera,
        R.drawable.ic_menu_camera
};

// Array of strings to store currencies
String[] currency = new String[]{
        "Indian Rupee",
        "Pakistani Rupee",
        "Sri Lankan Rupee",
        "Renminbi",
        "Bangladeshi Taka",
        "Nepalese Rupee",
        "Afghani",
        "North Korean Won",
        "South Korean Won",
        "Japanese Yen"
};

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    getActivity().setContentView(R.layout.fragment_date);

    // Each row in the list stores country name, currency and flag
    List<HashMap<String,String>> aList = new ArrayList<HashMap<String,String>>();

    for(int i=0;i<10;i++){
        HashMap<String, String> hm = new HashMap<String,String>();
        hm.put("txt", "Country : " + countries[i]);
        hm.put("cur","Currency : " + currency[i]);
        hm.put("flag", Integer.toString(flags[i]) );
        aList.add(hm);
    }

    // Keys used in Hashmap
    String[] from = { "flag","txt","cur" };

    // Ids of views in listview_layout
    int[] to = { R.id.flag,R.id.txt,R.id.cur};

    // Instantiating an adapter to store each items
    // R.layout.listview_layout defines the layout of each item
    SimpleAdapter adapter = new SimpleAdapter(getActivity().getBaseContext(), aList, R.layout.listview_layout, from, to);

    // Getting a reference to listview of main.xml layout file
    ListView listView = ( ListView ) getActivity().findViewById(R.id.listview);

    // Setting the adapter to the listView
    listView.setAdapter(adapter);
}
}

【问题讨论】：

需要重写Fragment类的onCreateView方法来设置当前Fragment的布局。目前通过使用getActivity().setContentView(R.layout.fragment_date);，您正在更改 Activity 的布局而不是 Fragment。请参阅Creating a Fragment 了解如何设置 Fragment 的布局。
请发布您的堆栈跟踪。
你没有遵循片段生命周期。

标签： java android listview android-fragments navigation-drawer

【解决方案1】：

了解fragments 更改您的代码，您可以使用 onCreateView、onViewCreated 和 onActivityCreated.onCreate 方法是使用初始化变量、对象或接收来自即将到来的活动的值或对象。

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    super.onCreateView(inflater, container, savedInstanceState);
    View v = inflater.inflate(R.layout.your_layout, container, false);

    tvTitle = (TextView) v.findViewById(R.id.tvTitle);
    ivLogo = (ImageView) v.findViewById(R.id.ivLogo);

    // Each row in the list stores country name, currency and flag 
    List<HashMap<String,String>> aList = new ArrayList<HashMap<String,String>>();

    for(int i=0;i<10;i++){
        HashMap<String, String> hm = new HashMap<String,String>();
        hm.put("txt", "Country : " + countries[i]);
        hm.put("cur","Currency : " + currency[i]);
        hm.put("flag", Integer.toString(flags[i]) );
        aList.add(hm);
    } 

    // Keys used in Hashmap 
    String[] from = { "flag","txt","cur" };

    // Ids of views in listview_layout 
    int[] to = { R.id.flag,R.id.txt,R.id.cur};

    // Instantiating an adapter to store each items 
    // R.layout.listview_layout defines the layout of each item 
    SimpleAdapter adapter = new SimpleAdapter(v.getContext(), aList, R.layout.listview_layout, from, to);

    // Getting a reference to listview of main.xml layout file 
    ListView listView = ( ListView ) v.findViewById(R.id.listview);

    // Setting the adapter to the listView 
    listView.setAdapter(adapter);

    return v;
}

【讨论】：

【解决方案2】：

从onCreate中删除此代码：

getActivity().setContentView(R.layout.fragment_date);

并添加此方法：

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    return inflater.inflate(R.layout.fragment_date, container, false);
}

UPD

这是您修改后的代码：

package boiko.taisiia.com.serialmania;

import android.content.Context;
import android.net.Uri;
import android.os.Bundle;
import android.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;


import android.widget.SimpleAdapter;

public class Date extends Fragment {

    // Array of strings storing country names
    String[] countries = new String[] {
            "India",
            "Pakistan",
            "Sri Lanka",
            "China",
            "Bangladesh",
            "Nepal",
            "Afghanistan",
            "North Korea",
            "South Korea",
            "Japan"
    };

    // Array of integers points to images stored in /res/drawable-ldpi/
    int[] flags = new int[]{
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera,
            R.drawable.ic_menu_camera
    };

    // Array of strings to store currencies
    String[] currency = new String[]{
            "Indian Rupee",
            "Pakistani Rupee",
            "Sri Lankan Rupee",
            "Renminbi",
            "Bangladeshi Taka",
            "Nepalese Rupee",
            "Afghani",
            "North Korean Won",
            "South Korean Won",
            "Japanese Yen"
    };

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);    

        // Each row in the list stores country name, currency and flag
        List<HashMap<String,String>> aList = new ArrayList<HashMap<String,String>>();

        for(int i=0;i<10;i++){
            HashMap<String, String> hm = new HashMap<String,String>();
            hm.put("txt", "Country : " + countries[i]);
            hm.put("cur","Currency : " + currency[i]);
            hm.put("flag", Integer.toString(flags[i]) );
            aList.add(hm);
        }

        // Keys used in Hashmap
        String[] from = { "flag","txt","cur" };

        // Ids of views in listview_layout
        int[] to = { R.id.flag,R.id.txt,R.id.cur};

        // Instantiating an adapter to store each items
        // R.layout.listview_layout defines the layout of each item
        SimpleAdapter adapter = new SimpleAdapter(getActivity().getBaseContext(), aList, R.layout.listview_layout, from, to);

        // Getting a reference to listview of main.xml layout file
        ListView listView = ( ListView ) getActivity().findViewById(R.id.listview);

        // Setting the adapter to the listView
        listView.setAdapter(adapter);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_date, container, false);
    }
}

【讨论】：

@TaisiiaBoiko 从代码中删除该行logger.v。
你没有遵循片段生命周期。
不幸的是，它又被压碎了

【解决方案3】：

解决方案

这不是在片段中设置内容的好方法！

代码

public final class YourFragment extends Fragment{

private TextView tvTitle;

private ImageView ivLogo;


/**
 * default and empty constructor
 * The constructor should stay empty
 */
public YourFragment()
{
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    super.onCreateView(inflater, container, savedInstanceState);
    View v = inflater.inflate(R.layout.your_layout, container, false);

    this.tvTitle = (TextView) v.findViewById(R.id.tvTitle);
    this.ivLogo = (ImageView) v.findViewById(R.id.ivLogo);
    return v;
}

// ...片段的其余部分

它应该做的工作！

希望对您有所帮助。

【讨论】：