Question

我正在尝试在一个活动中实现两个片段。一个包含列表视图，另一个包含网格视图。具有网格视图的片段在执行后不显示任何内容。

当它应该显示所有网格视图元素时显示空白

这是Pojo类

public class POJOMenuGrid {

String name;
String description;
int image;
public POJOMenuGrid(String name, String description, int image) {
    super();
    this.name = name;
    this.description = description;
    this.image = image;
}

public POJOMenuGrid() {
    super();
    // TODO Auto-generated constructor stub
}

public String getName() {
    return name;
}

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

public String getDescription() {
    return description;
}

public void setDescription(String description) {
    this.description = description;
}

public int getImage() {
    return image;
}

public void setImage(int image) {
    this.image = image;
}



}

这是适配器

public class MenuGridAdapter extends BaseAdapter{

Context context;
ArrayList<POJOMenuGrid> arr;
LayoutInflater inflater;



public MenuGridAdapter(Context context, ArrayList<POJOMenuGrid> arr) {
    super();
    this.context = context;
    this.arr = arr;

    inflater = (LayoutInflater)context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}

@Override
public int getCount() {
    // TODO Auto-generated method stub
    return 0;
}

@Override
public Object getItem(int arg0) {
    // TODO Auto-generated method stub
    return arr.get(arg0);
}

@Override
public long getItemId(int arg0) {
    // TODO Auto-generated method stub
    return 0;
}

/* (non-Javadoc)
 * @see android.widget.Adapter#getView(int, android.view.View, android.view.ViewGroup)
 */
@Override
public View getView(int arg0, View arg1, ViewGroup arg2) {
    // TODO Auto-generated method stub


        View v = inflater.inflate(R.layout.grid_single_item, null);
        System.out.println("in adapter 1");

    TextView itemName;
    TextView itemDescription;
    ImageView itemImage;
    Button plus;
    Button minus;
    TextView counter;
    System.out.println("in adapter 2");

    itemName  = (TextView)v.findViewById(R.id.itemName);
    itemDescription  = (TextView)v.findViewById(R.id.itemDescription);
    counter  = (TextView)v.findViewById(R.id.counter);
    itemImage  = (ImageView)v.findViewById(R.id.itemImage);
    plus = (Button)v.findViewById(R.id.plus);
    minus = (Button)v.findViewById(R.id.minus);
    System.out.println("in adapter 3");

    itemName.setText(arr.get(arg0).getName());
    itemDescription.setText(arr.get(arg0).getDescription());
    itemImage.setImageResource(arr.get(arg0).getImage());
    counter.setText("");

    System.out.println("in adapter 4");

    return v;
}


}

和Fragment类

public class Fragment2 extends Fragment{

GridView fragment2Grid;
POJOMenuGrid pojo;
MenuGridAdapter adapter;
ArrayList<POJOMenuGrid> arr;


String[] name = {"Manchow Soup","Clear Soup","Mushroom Soup","Corn Soup","Tomato Soup"};
String[] desc = {"Soya water with capsicum , carrots , medium spicy"};
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
        Bundle savedInstanceState) {
    // TODO Auto-generated method stub
    View v = inflater.inflate(R.layout.new_order_fragment_2, null);

    initialize();
    fragment2Grid = (GridView)v.findViewById(R.id.fragment2Grid);

    for(int i=0;i<5;i++)
    arr.add(new POJOMenuGrid(name[i], desc[0], R.drawable.ic_launcher));

    System.out.println(arr.get(0).getName()+" "+arr.get(0).getDescription()+" ");



    adapter = new MenuGridAdapter(v.getContext(), arr);
    fragment2Grid.setAdapter(adapter);
    System.out.println("adapter set");


    return v;
}
private void initialize() {
    // TODO Auto-generated method stub
    arr = new ArrayList<POJOMenuGrid>();
}
}

Answer 1

您尚未在

中设置观看次数

@Override
getCount();

和

中的ID

@Override
getItemId();

根据这些链接，有必要这样做

http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/5.1.1_r1/android/widget/GridView.java#GridView.lookForSelectablePosition%28int%2Cboolean%29
http://stackoverflow.com/questions/15545770/how-does-baseadapter-works-in-when-we-extend-it
http://grepcode.com/file/repository.grepcode.com/java/ext/com.google.android/android/5.1.1_r1/android/widget/BaseAdapter.java#BaseAdapter

如果getCount（）设置为零，BaseAdapter将返回空，GridView的setAdapter（）方法中的'position'变量将始终具有无效值。

Android：网格视图的内容不会显示在片段内

1 个答案: