【发布时间】:2017-01-10 19:11:12
【问题描述】:
在 ViewPager 中使用 firebase 的最佳方式是什么。
预期输出
如何将 ViewPager 与 Firebase 结合使用,以便它通知 Firebase 位置并相应地获取和附加数据?
Person.java
public class Person {
private String name;
private String email;
private String hobby;
public Person(){
}
public Person(String name , String email , String hobby){
this.name= name;
this.email = email;
this.hobby = hobby;
}
public void setName(String name) {
this.name = name;
}
public void setEmail(String email) {
this.email = email;
}
public void setHobby(String hobby) {
this.hobby = hobby;
}
public String getName() {
return name;
}
public String getEmail() {
return email;
}
public String getHobby() {
return hobby;
}
}
MainActivity.java
public class MainActivity extends AppCompatActivity {
private ViewPager viewPager;
// private FirebaseAuth mAuth;
List<Person> person;
private Context context;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
person = new ArrayList<>();
// mAuth = FirebaseAuth.getInstance();
context = this;
viewPager = (ViewPager) findViewById(R.id.pagerView);
viewPager.setAdapter(new MyPagerAdapter(getSupportFragmentManager(), person, context));
}
class MyPagerAdapter extends FragmentPagerAdapter {
String[] tabsArray;
private List<Person> personInAdapter = new ArrayList<>();
private Context context;
// int icons[] = {R.drawable.white_home, R.drawable.white_heart,
// R.drawable.white_star, R.drawable.white_heart, R.drawable.white_star};
public MyPagerAdapter(FragmentManager fm, List<Person> person, Context context) {
super(fm);
personInAdapter = person;
this.context = context;
tabsArray = getResources().getStringArray(R.array.TABS);
}
// @Override
// public CharSequence getPageTitle(int position) {
// return tabsArray[position];
// }
@Override
public Fragment getItem(int position) {
return MyFragment.getInstance(position );
}
@Override
public int getCount() {
return personInAdapter.size();
}
}
}
MyFragment.java
public class MyFragment extends Fragment {
private TextView upperText;
private TextView lowerText;
List<Person> personInAdapter = new ArrayList<>();
private Context context;
private DatabaseReference databaseReference;
public static MyFragment getInstance(int position) {
MyFragment myFragment = new MyFragment();
Bundle args = new Bundle();
args.putInt("position", position);
myFragment.setArguments(args);
return myFragment;
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_my, container, false);
upperText = (TextView) view.findViewById(R.id.myFragmentUpperText);
lowerText = (TextView) view.findViewById(R.id.myFragmentLowerText);
databaseReference = FirebaseUtil.getBaseRef().child("Person");
int i = getArguments().getInt("position");
ValueEventListener postListener = new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
// Get Post object and use the values to update the UI
for (DataSnapshot personSnapshot: dataSnapshot.getChildren()) {
Person person = personSnapshot.getValue(Person.class);
upperText.setText(person.getName());
lowerText.setText(person.getEmail());
Log.i("Data In Person ", person.toString());
}
// [END_EXCLUDE]
}
@Override
public void onCancelled(DatabaseError databaseError) {
// Getting Post failed, log a message
// [START_EXCLUDE]
}
};
databaseReference.addValueEventListener(postListener);
// Bundle bundle = getArguments();
// if (bundle != null) {
// textView.setText("The value is" +i);
// }
return view;
}
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
}
我已经用 FirebaseRecyclerView 尝试了 firebase,并在自定义 Recyclerview 中实现了同样的效果,它的工作原理就像魅力一样
FirebaseRecyclerAdapter<Blog, BlogViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Blog, BlogViewHolder>(
Blog.class,
R.layout.blog_row,
BlogViewHolder.class,
mDatabaseReference
) {
@Override
protected void populateViewHolder(BlogViewHolder viewHolder, Blog model, int position) {
viewHolder.setDesc(model.getDesc());
viewHolder.setTitle(model.getTitle());
viewHolder.setImage(getApplicationContext(), model.getImageUrl());
mGoogleNow.progressiveStop();
mGoogleNow.setVisibility(View.GONE);
}
};
mBlogList.setAdapter(firebaseRecyclerAdapter);
}
public void LogoutFromFirebase(View view) {
mAuth.signOut();
}
public static class BlogViewHolder extends RecyclerView.ViewHolder {
NetworkImageView networkImageView;
ImageLoader imageLoader;
View mView;
public BlogViewHolder(View itemView) {
super(itemView);
mView = itemView;
}
public void setTitle(String title) {
TextView sTitle = (TextView) mView.findViewById(R.id.TitleTextView);
sTitle.setText(title);
}
public void setDesc(String desc) {
TextView sDesc = (TextView) mView.findViewById(R.id.descriptionTextView);
sDesc.setText(desc);
}
public void setImage(Context context, String image) {
networkImageView = (NetworkImageView) mView.findViewById(R.id.imageBlogPost);
imageLoader = CustomVolleyRequest.getInstance(context)
.getImageLoader();
imageLoader.get(image, ImageLoader.getImageListener(networkImageView,
R.drawable.crop_image_menu_crop, android.R.drawable
.ic_dialog_alert));
networkImageView.setImageUrl(image, imageLoader);
// Picasso.with(context).load(image).into(networkImageView);
}
}
【问题讨论】:
-
你不能只使用一个firebase回收器适配器+水平线性布局管理器和回收器吗?您的视图可以占据整个屏幕,但这应该达到您想要的效果
-
是的,我确实考虑过,但是回收适配器 + 水平线性布局管理器的问题是,如果不使用外部库,我无法一次将滑动限制为单个元素。
-
您能否澄清一下“将滑动一次限制为单个元素”的意思
-
RecyclerView 设置为水平方向的问题是,向右或向左滑动它会滚动到多个元素,但我希望视图一次移动一个,就像 ViewPager 的情况一样
-
这就是我的意思,让 RecyclerView 适配器中的每个元素膨胀的视图全屏(每个项目的父布局膨胀整个屏幕)
标签: android firebase android-viewpager android-recyclerview firebase-realtime-database