列表视图无法显示

Question

我只是尝试在android中自定义ListView（带复选框）＆＃34; destination＆＃34;信息，对我来说很奇怪，因为Logcat没有错误，但Listview没有显示项目

我已经搜索了一整天的可能错误，但我可以找出真正的原因。请帮我！ THX！

这是我的来源：

ListView适配器的代码：

public class DestinationAdapter extends BaseAdapter {

private List<Destination> destinationList;

private static HashMap<Integer,Boolean> isSelected;

Context context;

LayoutInflater mInflater = null;


public DestinationAdapter(List<Destination> destinationList, Context context) {

    super();
    destinationList = new ArrayList<Destination>();

    this.context = context;
    this.destinationList = destinationList;

    mInflater = LayoutInflater.from(context);
    isSelected = new HashMap<Integer, Boolean>();


    init();
}



private void init(){
    for(int i=0; i< destinationList.size(); i++) {
        getIsSelected().put(i,false);
    }
}

@Override
public int getCount() {

    return destinationList.size();
}

@Override
public Destination getItem(int position) {

    return destinationList.get(position);
}

@Override
public long getItemId(int position) {

    return position;
}

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

    ViewHolder viewHolder;

    if (convertView == null) {
        convertView = mInflater.inflate(R.layout.destination_item, null);

        viewHolder = new ViewHolder();


        viewHolder.destinationImage = (ImageView) convertView.findViewById
                (R.id.destination_image);
        viewHolder.destinationName = (TextView) convertView.findViewById
                (R.id.destination_name);
        viewHolder.placeSelected = (CheckBox) convertView.findViewById
                (R.id.place_select);

        convertView.setTag(viewHolder); 
        }
    else {
        viewHolder = (ViewHolder) convertView.getTag(); 
        }


    viewHolder.destinationName.setText(destinationList.get(position).getName());
    viewHolder.destinationImage.setImageResource(destinationList.get(position).getImageId());
    viewHolder.placeSelected.setOnClickListener(new View.OnClickListener() {

        public void onClick(View v) {
            if (isSelected.get(position)) {
                isSelected.put(position, false);
                setIsSelected(isSelected);
            } else {
                isSelected.put(position, true);
                setIsSelected(isSelected);
            }
            notifyDataSetChanged();
        }
    });

    viewHolder.placeSelected.setChecked(getIsSelected().get(position));

    return convertView;
}


public static HashMap<Integer,Boolean> getIsSelected() {
    return isSelected;
}

public static void setIsSelected(HashMap<Integer,Boolean> isSelected) {
    DestinationAdapter.isSelected = isSelected;
}


class ViewHolder {
    ImageView destinationImage;
    TextView destinationName;
    CheckBox placeSelected;
}

}

和我的活动（我删除了其他显示的无关部分）：

public class DestinationActivity extends Activity {

private ListView listView;


private List<Destination> destinationList = new ArrayList<Destination>();

private DestinationAdapter adapter;

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


    listView = (ListView) findViewById(R.id.list_destination);


    initDestinations(); 

    adapter = new DestinationAdapter(destinationList, DestinationActivity.this);

    listView.setAdapter(adapter);

   }


//初始化数据
private void initDestinations() {
    Destination destination1 = new Destination("beijing", R.drawable.car);
    destinationList.add(destination1);
    Destination destination2 = new Destination("shanghai", R.drawable.car);
    destinationList.add(destination2);
    Destination destination3 = new Destination("hangzhou", R.drawable.car);
    destinationList.add(destination3);
    Destination destination4 = new Destination("guangzhou", R.drawable.car);
    destinationList.add(destination4);
    Destination destination5 = new Destination("shenzhen", R.drawable.car);
    destinationList.add(destination5);
    Destination destination6 = new Destination("zhuhai", R.drawable.car);
    destinationList.add(destination6);
    Destination destination7 = new Destination("xiamen", R.drawable.car);
    destinationList.add(destination7);
    Destination destination8 = new Destination("qingdao", R.drawable.car);
    destinationList.add(destination8);
    Destination destination9 = new Destination("jinan", R.drawable.car);
    destinationList.add(destination9);
    Destination destination10 = new Destination("zhengzhou", R.drawable.car);
    destinationList.add(destination10);
}

}

和目标对象：

public class Destination implements Serializable {

private int id;
private String name;
private int imageId;
private int priority;
private int rank;


// 经度
private double longitude;
// 纬度
private double latitute;



public Destination(double longitude, double latitute){
    this.longitude = longitude;
    this.latitute = latitute;
}

public Destination(String name, int imageId){
    this.name = name;
    this.imageId = imageId;
}

public Destination(int id, String name, int priority){
    this.id = id;
    this.name = name;
    this.priority = priority;
}



public double getLongitude()
{
    return longitude;
}

public void setLongitude(double longitude) {
    this.longitude = longitude;
}

public double getLatitute(){
    return latitute;
}

public void setLatitute(double latitute) {
    this.latitute = latitute;
}




public int getId() { return  id; }
public String getName() {
    return name;
}
public int getImageId() { return imageId; }
public int getPriority(){ return priority; }
public int getRank() {return rank;}

public void setName(String name){
    this.name = name;
}
public void setImageId(int imageId){
    this.imageId = imageId;
}
public void setId(int id){ this.id = id; }

}

两个布局xml：

item_destination.xml

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

<ImageView
    android:id="@+id/destination_image"
    android:layout_width="100dp"
    android:layout_height="100dp" />
<TextView
    android:id="@+id/destination_name"
    android:layout_width="wrap_content"
    android:layout_height="100dp"
    android:layout_gravity="center"
    android:layout_marginLeft="10dip" />

<CheckBox
    android:id="@+id/place_select"
    android:layout_width="100dp"
    android:layout_height="100dp"
    android:layout_alignParentRight="true"
    android:layout_marginRight="10dp"
    android:layout_centerVertical="true"
    android:focusable="false"
    android:clickable="false"
    android:focusableInTouchMode="false"   />

destination_layout.xml，listview只是它的一部分

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


<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="top"
    android:background="@drawable/border"
    android:orientation="horizontal"
    android:paddingBottom="@dimen/vertical_padding"
    android:paddingLeft="@dimen/horizontal_padding"
    android:paddingTop="@dimen/vertical_padding" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="45dp"
        android:layout_height="45dp"
        android:src="@drawable/departure" />


    <TextView
        android:id="@+id/from_place"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center"
        android:layout_weight="1"
        android:gravity="center"
        android:text="From"
        android:textSize="20dp" />
</LinearLayout>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="250dp"
    android:layout_gravity="top"
    android:background="@drawable/border"
    android:orientation="horizontal"
    android:paddingBottom="@dimen/vertical_padding"
    android:paddingLeft="@dimen/horizontal_padding"
    android:paddingTop="@dimen/vertical_padding" >

    <ImageView
        android:id="@+id/imageView2"
        android:layout_width="45dp"
        android:layout_height="45dp"
        android:src="@drawable/departure" />

<ListView
    android:id="@+id/list_destination"
    android:layout_marginLeft="10dp"
    android:layout_width="match_parent"
    android:layout_height="500dp" >
</ListView>
  </LinearLayout>

请帮帮我！这让我困惑了几天。 THX！

Answer 1

从适配器的构造函数中删除以下行。

destinationList = new ArrayList<Destination>();

您正在从适配器内部对列表进行新的引用。

  public DestinationAdapter(List<Destination> destinationList, Context context) {
      super();
      // Doing this you are creating new reference of passed argument. Delete it
      destinationList = new ArrayList<Destination>();
      // Here you are getting empty list due to above statement
      this.destinationList = destinationList;
  }