Android 片段中 ListView 的 setOnItemClickListener

setOnItemClickListener for ListView in a fragment

提问by Paresh Mayani

I'm having problems clicking on ListView items in the fragments. I wrote the code so the fragments point to layout files for everything and inside the 2 of the layouts are ListViews, which retrieve their entries from items in a string array in the strings.xml. I could not find a way to implement a setOnItemClickListener for each ListView item in my case due to the way I wrote the code.

我在单击片段中的 ListView 项目时遇到问题。我编写了代码，因此片段指向所有内容的布局文件，其中 2 个布局是 ListViews，它们从 strings.xml 中的字符串数组中的项目中检索它们的条目。由于我编写代码的方式，在我的情况下，我找不到为每个 ListView 项目实现 setOnItemClickListener 的方法。

MainActivity.java

主活动.java

package com.example.test_app;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.view.ViewPager;
import android.view.Menu;

public class MainActivity extends FragmentActivity{
    ViewPager ViewPager = null;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ViewPager= (ViewPager) findViewById(R.id.pager);
        FragmentManager fragmentManager=getSupportFragmentManager();
        ViewPager.setAdapter(new AdapterActivity(fragmentManager));
    }
    @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;
    }
}

AdapterActivity.java

适配器活动.java

package com.example.test_app;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

public class AdapterActivity extends FragmentStatePagerAdapter{
    public AdapterActivity(FragmentManager fm){
        super(fm);
    }
    @Override
    public Fragment getItem(int i){
        Fragment fragment=null;
        if(i==0){
            fragment=new HomeFragment();
        }
        if(i==1){
            fragment=new CommunityFragment();
        }
        if(i==2){
            fragment=new ResourcesFragment();
        }
        return fragment;
    }

    @Override
    public int getCount(){
        return 3;
    }

    @Override
    public CharSequence getPageTitle(int position){
        if(position==0){
            return "Home Page";
        }
        if(position==1){
            return "Community";
        }
        if(position==2){
            return "Resources";
        }
        return null;
    }
}
class HomeFragment extends Fragment{
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        return inflater.inflate(R.layout.home_fragment, container, false);
    }
}
class CommunityFragment extends Fragment{
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState){
        return inflater.inflate(R.layout.community_fragment, container, false);
    }
}
class ResourcesFragment extends Fragment{

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

Then in the resources_fragment.xml layout, there is a ListView

然后在resources_fragment.xml布局中，有一个ListView

<ListView
        android:id="@+id/resourcesListView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:entries="@array/categories" >
</ListView>

It grabs entries from strings.xml

它从 strings.xml 中获取条目

<string-array name="categories">
        <item>Category 1</item>
        <item>Category 2</item>
        <item>Category 3</item>
        <item>Category 4</item>
        <item>Category 5</item>
        <item>Category 6</item>
        <item>Category 7</item>
        <item>Category 8</item>
</string-array>

I used this link to create my ListView, but the setOnItemClickListener won't work for me. How else can I connect each listview item other activities?

我使用此链接创建了我的 ListView，但 setOnItemClickListener 对我不起作用。我还能如何将每个列表视图项与其他活动连接起来？

回答by NameSpace

The place to add your ListView.SetOnItemClickListener is in your fragment creation code, after you inlfate the layouts. Use findViewById to find your ListView, and add your setOnItemClick listener.

添加您的 ListView.SetOnItemClickListener 的位置在您的片段创建代码中，在您膨胀布局之后。使用 findViewById 查找您的 ListView，并添加您的 setOnItemClick 侦听器。

class ResourcesFragment extends Fragment{

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

        View view = inflater.inflate(R.layout.resources_fragment, container, false);
        ListView lv = (ListView) view.findViewById(R.id.mylistviewid);

        lv.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> arg0, View arg1,
                    int position, long arg3) {
                // TODO Auto-generated method stub

                        String category = categories[position];
                        Class activityClass = lookupActivityClass_byName(category);
                        //You could lookup by position, but "name" is more general

                        Intent intent = new Intent(getActivity(), activityClass);
                        startActivity(intent);


            }
        });

        return view;

    }

回答by Paresh Mayani

When you use Fragment, you can find views inside onCreateView(). In simpler term, it's same as of onCreate()of Activity.

使用的时候Fragment，可以在里面找到views onCreateView()。在简单来说，它是一样的onCreate()的Activity。

So in this case, find ListViewinside onCreateView()and assign onItemClickListenerthere only.

所以在这种情况下，只ListView在里面找到onCreateView()并分配onItemClickListener。