Question

我正在开发一个社交网络应用程序，我需要一个活动，在parse.com中显示我的用户表中的所有数据。我试过这段代码，但结果总是一个空的空白屏幕。这是活动的代码

public class UsersList extends Activity {
private ParseQueryAdapter<Userr> mainAdapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_users_list);
    ListView listhope = (ListView) findViewById(R.id.userlistlist);
    mainAdapter = new MyParseUserListAdaptor(this, Userr.class);
    listhope.setAdapter(mainAdapter);
    mainAdapter.loadObjects();
 }
  [...]
}

这是listview的布局文件

<LinearLayout
android:orientation="vertical"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_height="match_parent"
android:layout_width="match_parent"
android:id="@+id/usslist">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/userlistlist"
 />
</LinearLayout>

这是我创建的自定义适配器

public class MyParseUserListAdaptor extends ParseQueryAdapter<Userr> {

public MyParseUserListAdaptor(Context context,
                           Class<?extends ParseUser> clazz) {
    super(context, clazz);
    // TODO Auto-generated constructor stub
}

@Override
public View getItemView(Userr userme, View v, ViewGroup parent) {

    if (v == null) {
        v = View.inflate(getContext(), R.layout.usertem, null);
    }

    super.getItemView(userme, v, parent);

    ParseImageView userlistpic = (ParseImageView) v.findViewById(R.id.imageView);
    TextView userListName = (TextView) v.findViewById(R.id.userName);
    TextView userListEmail = (TextView) v.findViewById(R.id.userEmail);

    userlistpic.setParseFile(userme.getPhotoFile());
    userListName.setText(userme.getUser_Name(ParseUser.getCurrentUser()));
    userListEmail.setText(userme.getUser_Email(ParseUser.getCurrentUser()));
    userlistpic.loadInBackground();

    return v;
}
}

这是我的Userr类

@ParseClassName("Userr")
public class Userr extends ParseUser {

public Userr() {
    // A default constructor is required.
}

最后这是listview项目布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/userittem">

<com.parse.ParseImageView
    android:id="@+id/imageView"
    android:layout_width="80dp"
    android:layout_height="80dp"
    android:layout_alignParentTop="true"
    android:layout_alignParentStart="true" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceLarge"
    android:text="Mohamed Sherif"
    android:id="@+id/userName"
    android:layout_alignParentTop="true"
    android:layout_toEndOf="@+id/imageView" />

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:textAppearance="?android:attr/textAppearanceMedium"
    android:text="mohamedsherifhazem@gmail.com"
    android:id="@+id/userEmail"
    android:layout_below="@+id/userName"
    android:layout_toEndOf="@+id/imageView" />

 </RelativeLayout>

代码：

public String getUser_Name(ParseUser user) {
    String name =  user.get("name").toString();
    if (name != null)
        return name;
    else return "Anonymous";
}

public String getUser_Email(ParseUser user) {
    String email =  user.getEmail();
    if (email != null)
        return email;
    else return "Anonymous";
}

public ParseFile getPhotoFile() {
    return getParseFile("profile_picture");
}
}

如何使用listview

0 个答案: