Java tutorial
/* * Copyright 2016 Google Inc. All Rights Reserved. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package com.akalizakeza.apps.ishusho.activity; import android.content.Intent; import android.os.Bundle; import android.support.design.widget.CollapsingToolbarLayout; import android.support.design.widget.FloatingActionButton; import android.support.v4.content.ContextCompat; import android.support.v7.app.AppCompatActivity; import android.support.v7.widget.GridLayoutManager; import android.support.v7.widget.RecyclerView; import android.support.v7.widget.Toolbar; import android.util.Log; import android.view.View; import android.view.ViewGroup; import android.widget.GridView; import android.widget.ImageView; import android.widget.TextView; import android.widget.Toast; import com.akalizakeza.apps.ishusho.R; import com.akalizakeza.apps.ishusho.models.Person; import com.akalizakeza.apps.ishusho.models.Post; import com.google.firebase.auth.FirebaseUser; import com.google.firebase.database.DataSnapshot; import com.google.firebase.database.DatabaseError; import com.google.firebase.database.DatabaseReference; import com.google.firebase.database.ValueEventListener; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import de.hdodenhof.circleimageview.CircleImageView; public class UserDetailActivity extends AppCompatActivity { public final static String USER_EXTRA_NAME = "user"; public final static String USER_ID_EXTRA_NAME = "userid"; private static final int GRID_NUM_COLUMNS = 2; private final String TAG = "UserDetailActivity"; private RecyclerView mRecyclerGrid; private GridAdapter mGridAdapter; private ValueEventListener mFollowingListener; private ValueEventListener mPersonInfoListener; private String mUserId; private DatabaseReference mPeopleRef; private DatabaseReference mPersonRef; private String mUser; private FirebaseUser firebaseUser; private DatabaseReference mFollowersRef; private ValueEventListener mFollowersListener; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_user_detail); Intent intent = getIntent(); mUserId = intent.getStringExtra(USER_ID_EXTRA_NAME); mUser = intent.getStringExtra(USER_EXTRA_NAME); final Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar); setSupportActionBar(toolbar); getSupportActionBar().setDisplayHomeAsUpEnabled(true); final CollapsingToolbarLayout collapsingToolbar = (CollapsingToolbarLayout) findViewById( R.id.collapsing_toolbar); // TODO: Investigate why initial toolbar title is activity name instead of blank. mPeopleRef = FirebaseUtil.getPeopleRef(); final String currentUserId = FirebaseUtil.getCurrentUserId(); final FloatingActionButton followUserFab = (FloatingActionButton) findViewById(R.id.follow_user_fab); mFollowingListener = new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { if (dataSnapshot.exists()) { followUserFab.setImageDrawable( ContextCompat.getDrawable(UserDetailActivity.this, R.drawable.ic_done_black_48dp)); } else { followUserFab.setImageDrawable(ContextCompat.getDrawable(UserDetailActivity.this, R.drawable.ic_person_follow_black_48dp)); } } @Override public void onCancelled(DatabaseError firebaseError) { } }; if (currentUserId != null) { mPeopleRef.child(currentUserId).child("following").child(mUserId) .addValueEventListener(mFollowingListener); } followUserFab.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View view) { if (currentUserId == null) { Toast.makeText(UserDetailActivity.this, "You need to sign in to follow someone.", Toast.LENGTH_SHORT).show(); return; } // TODO: Convert these to actually not be single value, for live updating when // current user follows. mPeopleRef.child(currentUserId).child("following").child(mUserId) .addListenerForSingleValueEvent(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { Map<String, Object> updatedUserData = new HashMap<>(); if (dataSnapshot.exists()) { // Already following, need to unfollow updatedUserData.put("people/" + currentUserId + "/following/" + mUserId, null); updatedUserData.put("followers/" + mUserId + "/" + currentUserId, null); } else { updatedUserData.put("people/" + currentUserId + "/following/" + mUserId, true); updatedUserData.put("followers/" + mUserId + "/" + currentUserId, true); } FirebaseUtil.getBaseRef().updateChildren(updatedUserData, new DatabaseReference.CompletionListener() { @Override public void onComplete(DatabaseError firebaseError, DatabaseReference firebase) { if (firebaseError != null) { Toast.makeText(UserDetailActivity.this, R.string.follow_user_error, Toast.LENGTH_LONG).show(); Log.d(TAG, getString(R.string.follow_user_error) + "\n" + firebaseError.getMessage()); } } }); } @Override public void onCancelled(DatabaseError firebaseError) { } }); } }); mRecyclerGrid = (RecyclerView) findViewById(R.id.user_posts_grid); mGridAdapter = new GridAdapter(); mRecyclerGrid.setAdapter(mGridAdapter); mRecyclerGrid.setLayoutManager(new GridLayoutManager(this, GRID_NUM_COLUMNS)); mPersonRef = FirebaseUtil.getPeopleRef().child(mUserId); mPersonInfoListener = mPersonRef.addValueEventListener (new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { Person person = dataSnapshot.getValue(Person.class); CircleImageView userPhoto = (CircleImageView) findViewById(R.id.user_detail_photo); GlideUtil.loadProfileIcon(person.getProfile_picture(), userPhoto); String name = mUser; if (name == null) { name = getString(R.string.user_info_no_name); } collapsingToolbar.setTitle(name); if (person.getFollowing() != null) { int numFollowing = person.getFollowing().size(); ((TextView) findViewById(R.id.user_num_following)).setText(numFollowing + " following"); } List<String> paths = new ArrayList<String>(person.getPosts().keySet()); mGridAdapter.addPaths(paths); String firstPostKey = paths.get(0); FirebaseUtil.getPostsRef().child(firstPostKey) .addListenerForSingleValueEvent(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { Post post = dataSnapshot.getValue(Post.class); ImageView imageView = (ImageView) findViewById(R.id.backdrop); GlideUtil.loadImage(post.getFull_url(), imageView); } @Override public void onCancelled(DatabaseError firebaseError) { } }); } @Override public void onCancelled(DatabaseError firebaseError) { } }); mFollowersRef = FirebaseUtil.getFollowersRef().child(mUserId); mFollowersListener = new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { long numFollowers = dataSnapshot.getChildrenCount(); ((TextView) findViewById(R.id.user_num_followers)) .setText(numFollowers + " follower" + (numFollowers == 1 ? "" : "s")); } @Override public void onCancelled(DatabaseError databaseError) { } }; mFollowersRef.addValueEventListener(mFollowersListener); } @Override protected void onDestroy() { if (FirebaseUtil.getCurrentUserId() != null) { mPeopleRef.child(FirebaseUtil.getCurrentUserId()).child("following").child(mUserId) .removeEventListener(mFollowingListener); } mPersonRef.child(mUserId).removeEventListener(mPersonInfoListener); mFollowersRef.removeEventListener(mFollowersListener); super.onDestroy(); } @Override public boolean onSupportNavigateUp() { finish(); return super.onSupportNavigateUp(); } class GridAdapter extends RecyclerView.Adapter<GridImageHolder> { private List<String> mPostPaths; public GridAdapter() { mPostPaths = new ArrayList<String>(); } @Override public GridImageHolder onCreateViewHolder(ViewGroup parent, int viewType) { ImageView imageView = new ImageView(UserDetailActivity.this); int tileDimPx = getPixelsFromDps(100); imageView.setLayoutParams(new GridView.LayoutParams(tileDimPx, tileDimPx)); imageView.setScaleType(ImageView.ScaleType.CENTER_CROP); imageView.setPadding(8, 8, 8, 8); return new GridImageHolder(imageView); } @Override public void onBindViewHolder(final GridImageHolder holder, int position) { DatabaseReference ref = FirebaseUtil.getPostsRef().child(mPostPaths.get(position)); ref.addListenerForSingleValueEvent(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { Post post = dataSnapshot.getValue(Post.class); GlideUtil.loadImage(post.getFull_url(), holder.imageView); holder.imageView.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // TODO: Implement go to post view. Toast.makeText(UserDetailActivity.this, "Selected: " + holder.getAdapterPosition(), Toast.LENGTH_SHORT).show(); } }); } @Override public void onCancelled(DatabaseError firebaseError) { Log.e(TAG, "Unable to load grid image: " + firebaseError.getMessage()); } }); } public void addPath(String path) { mPostPaths.add(path); notifyItemInserted(mPostPaths.size()); } public void addPaths(List<String> paths) { int startIndex = mPostPaths.size(); mPostPaths.addAll(paths); notifyItemRangeInserted(startIndex, mPostPaths.size()); } @Override public int getItemCount() { return mPostPaths.size(); } private int getPixelsFromDps(int dps) { final float scale = UserDetailActivity.this.getResources().getDisplayMetrics().density; return (int) (dps * scale + 0.5f); } } private class GridImageHolder extends RecyclerView.ViewHolder { public ImageView imageView; public GridImageHolder(ImageView itemView) { super(itemView); imageView = itemView; } } }