Isabellle

public static void showHashKey(Context context) {
            try {
                PackageInfo info = context.getPackageManager().getPackageInfo(
                        "com.example.yourpackagename", PackageManager.GET_SIGNATURES); //Your            package name here
                for (Signature signature : info.signatures) {
                    MessageDigest md = MessageDigest.getInstance("SHA");
                    md.update(signature.toByteArray());
                    Log.i("KeyHash:", Base64.encodeToString(md.digest(), Base64.DEFAULT));
                    }
            } catch (NameNotFoundException e) {

Isabellle

public class BaseActivity extends Activity implements OnConnectivityChangedListener {

    private ConnectivityChangeReceiver connectivityChangeReceiver;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        connectivityChangeReceiver = new ConnectivityChangeReceiver(this);
        IntentFilter filter = new IntentFilter();
        filter.addAction("android.net.conn.CONNECTIVITY_CHANGE");
        registerReceiver(connectivityChangeReceiver, filter);

Isabellle

Make button move up when softkeyboard is shown
<activity android:windowSoftInputMode="adjustPan"> </activity>

Put next or done on SoftKeyboard
android:imeOptions="actionNext"
android:imeOptions="actionSend"

Empty states in Android, best practices
https://www.reddit.com/r/androiddev/comments/3bjnxi/best_way_to_handle_recyclerview_empty_state/https://www.reddit.com/r/androiddev/comments/3bjnxi/best_way_to_handle_recyclerview_empty_state/

Isabellle

itemTitle.requestFocus();
        InputMethodManager imm = (InputMethodManager) getActivity().getSystemService(Context.INPUT_METHOD_SERVICE);
        imm.showSoftInput(itemTitle, InputMethodManager.SHOW_IMPLICIT);

Isabellle

Picasso.with(context)
                    .load(item.getFrontImage())
                    .into(itemFrontImage);

Isabellle

//Based on the link: Why doesn't RecyclerView have onItemClickListener()? and How RecyclerView is different from Listview?, and also @Duncan's general idea, I give my solution here:

//define one interface 'RecyclerViewClickListener' for passing message from adapter to Activity/Fragment:
public interface RecyclerViewClickListener
{

     public void recyclerViewListClicked(View v, int position);
}
//In Activity/Fragment implement the interface, and also pass listener to adapter:
@Override

Isabellle

package isabelle.com.requestpermissiondemo;

import android.Manifest;
import android.annotation.TargetApi;
import android.content.DialogInterface;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.v7.app.AlertDialog;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;

Isabellle

package com.google.firebase.zerotoapp;

public class ChatMessage {
    public String name;
    public String message;

    public ChatMessage() {
    }

    public ChatMessage(String name, String message) {

Isabellle

package com.yatoo.adapter.recyclerView;


import android.support.v7.widget.RecyclerView;
import android.view.ViewGroup;

/**
 * Created by student5303 on 4/04/16.
 */
public abstract class ClickableRecyclerViewAdapter<VH extends com.yatoo.adapter.recyclerView.ClickableViewHolder> extends RecyclerView.Adapter implements com.yatoo.adapter.recyclerView.ClickableViewHolder.ClickableViewHolderListener {

Isabellle

package com.yatoo.activity;

import android.content.Intent;
import android.os.Bundle;
import android.support.v7.widget.GridLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.util.Log;
import android.view.View;
import android.widget.LinearLayout;