如何将带有 ListView 的 Activity 转换为 Fragment？

Question

我用Activity 创建了一个ListView；但我需要用Fragment 创建一个ListView。

这是我Activity的截图：

这是对应的代码：

public class Main extends ActionBarActivity implements
        android.widget.CompoundButton.OnCheckedChangeListener {

    ListView lv;
    ArrayList<Planet> planetList;
    PlanetAdapter plAdapter;

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

        lv = (ListView) findViewById(R.id.listview);
        displayPlanetList();


    }

    private void displayPlanetList() {

        planetList = new ArrayList<Planet>();
        planetList.add(new Planet("Margherita", 6, "€"));
        planetList.add(new Planet("Diavola", 7,"€"));
        planetList.add(new Planet("Bufalina", 5,"€"));
        planetList.add(new Planet("Marinara", 5,"€"));
        planetList.add(new Planet("Viennese", 4,"€"));

        plAdapter = new PlanetAdapter(planetList, this);
        lv.setAdapter(plAdapter);
    }

    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

        int pos = lv.getPositionForView(buttonView);
        if (pos != ListView.INVALID_POSITION) {
            Planet p = planetList.get(pos);
            p.setSelected(isChecked);


            /*Toast.makeText(
                    this,
                    "Clicked on Planet: " + p.getName() + ". State: is "
                            + isChecked, Toast.LENGTH_SHORT).show();*/
        }

    }
    public void showResult(View v) {
        String result = "Selected Product are :";
        int totalAmount=0;

        for (Planet p : plAdapter.getBox()) {
            if (p.selected){
                result += "\n" + p.name+" "+p.distance+"€"+"q.tà :"+p.getQuantità();
                //if (p.quantità.equals("") && p.quantità.equals(null) ){
                System.out.println("leggo questo record:"+p.name + " " + p.distance + " " + p.quantità );

                System.out.println("leggo questo p.getquatità :"+p.quantità );
                //}
                //else{
                    System.out.println("leggo questo in p.quantità: "+p.getQuantità());
                    int quantitaInt= Integer.parseInt(p.getQuantità() );
                    totalAmount+=p.distance * quantitaInt;
                //}
            }
        }
//      Toast.makeText(this, result+"\n"+"Total Amount:="+totalAmount, Toast.LENGTH_LONG).show();
        //Integer.toString(totalAmount);
        Intent i = new Intent(Main.this, SecondActivity.class);
        i.putExtra("NomeDati1", result);
        i.putExtra("NomeDati2", String.valueOf(totalAmount));
        startActivity(i);

    }
}

class Planet {

    String name;
    int distance;
    String quantità;
    String valuta;
    boolean selected = false;



    public Planet(String name, int distance, String quantità) {
        super();
        this.name = name;
        this.distance = distance;
        this.quantità = quantità;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getDistance() {
        return distance;
    }

    public void setDistance(int distance) {
        this.distance = distance;
    }

    public boolean isSelected() {
        return selected;
    }

    public void setSelected(boolean selected) {
        this.selected = selected;
    }

    public String getQuantità() {
        return quantità;
    }

    public void setQuantità(String quantità) {
        this.quantità = quantità;
    }
    public String getValuta() {
        return valuta;
    }

    public void setValuta(String valuta) {
        this.valuta = valuta;
    }

}

public class PlanetAdapter extends ArrayAdapter<Planet>{

    private List<Planet> planetList;
    private Context context;
    ArrayList<Planet> objects;


    public PlanetAdapter(List<Planet> planetList, Context context) {
        super(context, R.layout.single_listview_item, planetList);
        this.planetList = planetList;
        this.context = context;
    }

    public  class PlanetHolder {
        public TextView planetName;
        public TextView distView;
        public CheckBox chkBox;
        public EditText edit;
        public String quantità;



    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {

View row = convertView;
        PlanetHolder holder = null;
        if (row == null) {
            LayoutInflater inflater = ((Activity) context).getLayoutInflater();
            row = inflater.inflate(R.layout.single_listview_item, parent, false);
            holder = new PlanetHolder();
            holder.planetName = (TextView) row.findViewById(R.id.name);
            holder.distView = (TextView) row.findViewById(R.id.dist);
            holder.chkBox = (CheckBox) row.findViewById(R.id.chk_box);
            holder.edit = (EditText) row.findViewById(R.id.editText);
            holder.edit.setVisibility(View.GONE);
            holder.edit.setEnabled(false);
            row.setTag(holder);
        } else {
            holder = (PlanetHolder) row.getTag();
        }
        final Planet p = planetList.get(position);

        holder.chkBox.setOnCheckedChangeListener((Main) context);
        final PlanetHolder finalHolder = holder;
        holder.chkBox.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (finalHolder.chkBox.isChecked()) {
                    finalHolder.edit.setVisibility(View.VISIBLE);
                    finalHolder.edit.setEnabled(true);
                    finalHolder.edit.addTextChangedListener(new TextWatcher() {
                        @Override
                        public void beforeTextChanged(CharSequence s, int start, int count, int after) {
                        }

                        @Override
                        public void onTextChanged(CharSequence s, int start, int before, int count) {
                        }

                        @Override
                        public void afterTextChanged(Editable s) {
                            p.setQuantità(finalHolder.edit.getText().toString().trim());
                        }
                    });
                } else {
                    finalHolder.edit.setVisibility(View.GONE);
                    finalHolder.edit.setEnabled(false);
                    finalHolder.edit.setText(null);
                }
            }
        });
        holder.planetName.setText(p.getName());
        holder.distView.setText("" + p.getDistance());
        holder.chkBox.setChecked(p.isSelected());
        holder.chkBox.setTag(p);
        holder.edit.setEnabled(false);

        return row;
    }


    ArrayList<Planet> getBox() {
        ArrayList<Planet> box = new ArrayList<Planet>();
        for (Planet p : planetList) {
            if (p.selected)
                box.add(p);
        }
        return box;
    }


}

MAIN.XML：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <ListView
        android:id="@+id/listview"
        android:layout_width="fill_parent"
        android:layout_height="400dp">

    </ListView>
    <Button
        android:layout_width="200dp"
        android:layout_height="wrap_content"
        android:layout_gravity="center_horizontal"
        android:onClick="showResult"
        android:text="get_answer">
    </Button>


</LinearLayout>

SINGLE_LISTVIEW_ITEM XML：

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal" >

    <CheckBox 
        android:id="@+id/chk_box"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true" />
    <LinearLayout
        android:id="@+id/linearLayout1"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5dp"
        android:orientation="vertical"
        android:layout_weight="1" >

    <TextView
        android:id="@+id/name"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_toRightOf="@id/chk_box"
        android:textStyle="bold" />

    <TextView
        android:id="@+id/dist"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_below="@id/name"
        android:layout_toRightOf="@id/chk_box"
        android:textSize="12sp"
        android:textStyle="italic" />
    <EditText
        android:layout_width="196dp"
        android:layout_height="wrap_content"
        android:inputType="number"
        android:ems="10"
        android:id="@+id/editText"
        android:hint="quantità"
        >
    </EditText>
    </LinearLayout>

</LinearLayout>

Answer 1

我强烈建议使用 RecyclerView 而不是 ListView。 对于您的问题，您可以在类似于活动本身的片段中创建列表视图。
您需要将您的活动代码放在片段中并在活动中加载片段

Activity xml 应该是这样的

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"  android:id="@+id/fragmentContainer"
android:layout_width="match_parent"
android:layout_height="match_parent" ></LinearLayout>

片段 xml 应该是这样的

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
>


<ListView
    android:id="@+id/list_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"/>

</RelativeLayout>

你的活动应该是这样的

public class Main extends AppCompatActivity {


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

       getSupportFragmentManager().beginTransaction().
            replace(R.id.fragmentContainer, new MyListFragment()).commit();


}
}

你的片段应该是这样的

public class MyListFragment extends Fragment implements
    android.widget.CompoundButton.OnCheckedChangeListener {

ListView lv;
ArrayList<Planet> planetList;
PlanetAdapter plAdapter;

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    return inflater.inflate(R.layout.fragment_view, container, false);
}


@Override
public void onViewCreated(View view, @Nullable Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);

     lv = (ListView) findViewById(R.id.listview);
    displayPlanetList();
}


private void displayPlanetList() {

    planetList = new ArrayList<Planet>();
    planetList.add(new Planet("Margherita", 6, "€"));
    planetList.add(new Planet("Diavola", 7,"€"));
    planetList.add(new Planet("Bufalina", 5,"€"));
    planetList.add(new Planet("Marinara", 5,"€"));
    planetList.add(new Planet("Viennese", 4,"€"));

    plAdapter = new PlanetAdapter(planetList, this);
    lv.setAdapter(plAdapter);
}


 @Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

    int pos = lv.getPositionForView(buttonView);
    if (pos != ListView.INVALID_POSITION) {
        Planet p = planetList.get(pos);
        p.setSelected(isChecked);


        /*Toast.makeText(
                this,
                "Clicked on Planet: " + p.getName() + ". State: is "
                        + isChecked, Toast.LENGTH_SHORT).show();*/
    }

}
public void showResult(View v) {
    String result = "Selected Product are :";
    int totalAmount=0;

    for (Planet p : plAdapter.getBox()) {
        if (p.selected){
            result += "\n" + p.name+" "+p.distance+"€"+"q.tà :"+p.getQuantità();
            //if (p.quantità.equals("") && p.quantità.equals(null) ){
            System.out.println("leggo questo record:"+p.name + " " + p.distance + " " + p.quantità );

            System.out.println("leggo questo p.getquatità :"+p.quantità );
            //}
            //else{
                System.out.println("leggo questo in p.quantità: "+p.getQuantità());
                int quantitaInt= Integer.parseInt(p.getQuantità() );
                totalAmount+=p.distance * quantitaInt;
            //}
        }
    }
//      Toast.makeText(this, result+"\n"+"Total Amount:="+totalAmount, Toast.LENGTH_LONG).show();
    //Integer.toString(totalAmount);
    Intent i = new Intent(getActivity(), SecondActivity.class);
    i.putExtra("NomeDati1", result);
    i.putExtra("NomeDati2", String.valueOf(totalAmount));
    startActivity(i);

}
}

您的适配器类保持原样。

Answer 2

你可以试试ListFragment

http://developer.android.com/reference/android/app/ListFragment.html

检查这个教程： http://www.tutorialspoint.com/android/android_list_fragment.htm

Answer 3

这是你的Activity类转换成片段

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CompoundButton;
import android.widget.ListView;

public class Main extends Fragment implements android.widget.CompoundButton.OnCheckedChangeListener {

    private ListView lv;
    private ArrayList<Planet> planetList;
    private PlanetAdapter plAdapter;

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

        lv = (ListView) rootView.findViewById(R.id.listview);

        displayPlanetList();

        return rootView;

    }

    private void displayPlanetList() {

        planetList = new ArrayList<Planet>();
        planetList.add(new Planet("Margherita", 6, "€"));
        planetList.add(new Planet("Diavola", 7, "€"));
        planetList.add(new Planet("Bufalina", 5, "€"));
        planetList.add(new Planet("Marinara", 5, "€"));
        planetList.add(new Planet("Viennese", 4, "€"));

        plAdapter = new PlanetAdapter(planetList, getActivity());
        lv.setAdapter(plAdapter);
    }

    @Override
    public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

        int pos = lv.getPositionForView(buttonView);
        if (pos != ListView.INVALID_POSITION) {
            Planet p = planetList.get(pos);
            p.setSelected(isChecked);

            /*
             * Toast.makeText( this, "Clicked on Planet: " + p.getName() +
             * ". State: is " + isChecked, Toast.LENGTH_SHORT).show();
             */
        }

    }

    public void showResult(View v) {
        String result = "Selected Product are :";
        int totalAmount = 0;

        for (Planet p : plAdapter.getBox()) {
            if (p.selected) {
                result += "\n" + p.name + " " + p.distance + "€" + "q.tà :" + p.getQuantità();
                // if (p.quantità.equals("") && p.quantità.equals(null) ){
                System.out.println("leggo questo record:" + p.name + " " + p.distance + " " + p.quantità);

                System.out.println("leggo questo p.getquatità :" + p.quantità);
                // }
                // else{
                System.out.println("leggo questo in p.quantità: " + p.getQuantità());
                int quantitaInt = Integer.parseInt(p.getQuantità());
                totalAmount += p.distance * quantitaInt;
                // }
            }
        }
        // Toast.makeText(this, result+"\n"+"Total Amount:="+totalAmount,
        // Toast.LENGTH_LONG).show();
        // Integer.toString(totalAmount);
        Intent i = new Intent(getActivity(), SecondActivity.class);
        i.putExtra("NomeDati1", result);
        i.putExtra("NomeDati2", String.valueOf(totalAmount));
        startActivity(i);

    }
}