<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="demo.mukesh.app.com.myapplication">

    <uses-permission android:name="android.permission.INTERNET"/>

    <application
            android:allowBackup="true"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:roundIcon="@mipmap/ic_launcher_round"
            android:supportsRtl="true"
            android:theme="@style/AppTheme">
        <activity android:name=".activity.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

    </application>

</manifest>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
          package="demo.mukesh.app.com.myapplication">

    <uses-permission android:name="android.permission.INTERNET"/>

    <application
            android:allowBackup="true"
            android:icon="@mipmap/ic_launcher"
            android:label="@string/app_name"
            android:roundIcon="@mipmap/ic_launcher_round"
            android:supportsRtl="true"
            android:theme="@style/AppTheme">
        <activity android:name=".activity.MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN"/>

                <category android:name="android.intent.category.LAUNCHER"/>
            </intent-filter>
        </activity>

    </application>

</manifest>

2.Open build.gradle and add Retrofit, Gson dependencies

dependencies {

    implementation 'com.android.support:recyclerview-v7:27.1.1'

//retrofit, gson
    implementation 'com.squareup.retrofit2:retrofit:2.1.0'
    implementation 'com.google.code.gson:gson:2.6.2'
    implementation 'com.squareup.retrofit2:converter-gson:2.1.0'

public class Test {
    @SerializedName("userId")
    @Expose
    private Integer userId;
    @SerializedName("id")
    @Expose
    private Integer id;
    @SerializedName("title")
    @Expose
    private String title;
    @SerializedName("body")
    @Expose
    private String body;

    public Integer getUserId() {
        return userId;
    }

    public void setUserId(Integer userId) {
        this.userId = userId;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getBody() {
        return body;
    }

    public void setBody(String body) {
        this.body = body;
    }
}

public interface APIInterface {

    @GET("posts")
    Call<ArrayList<Test>> getALLData();

}

5.Create APIClient.java Setting Up the Retrofit Interface

public class APIClient {
    private static String BASE_URL="https://jsonplaceholder.typicode.com/";
    private static Retrofit retrofit = null;

    public static Retrofit getClient() {

        retrofit = new Retrofit.Builder()
                .baseUrl(BASE_URL)
                .addConverterFactory(GsonConverterFactory.create())
                //.client(client)
                .build();

        return retrofit;
    }

}

 

6. MyAdapter.java

public class MyAdapter extends RecyclerView.Adapter<MyAdapter.MyViewHolder> {
    private Context context;
    private ArrayList<Test> arrTest;

    public MyAdapter(Context context, ArrayList<Test> arrTest) {
        this.context = context;
        this.arrTest = arrTest;

    }

    public MyViewHolder onCreateViewHolder(@NonNull ViewGroup parent, int viewType) {
        View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.row_items, parent, false);
        return new MyViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        Test test= arrTest.get(position);
        holder.title.setText(test.getTitle());
        holder.desc.setText(test.getBody());

    }

    @Override
    public int getItemCount() {
        return arrTest.size();
    }

    public class MyViewHolder extends RecyclerView.ViewHolder {
        TextView title,desc;

        public MyViewHolder(View itemView) {
            super(itemView);
            title=(TextView)itemView.findViewById(R.id.tvTitle);
            desc=(TextView)itemView.findViewById(R.id.tvDesc);
        }
    }
}

7.MainActivity.java

public class MainActivity extends AppCompatActivity {
    private ArrayList<Test> arrTest;
    private Activity activity;
    private RecyclerView recyclerView;
    private MyAdapter adapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        callAPI();
    }

    private void callAPI() {
        APIInterface apiInterface = APIClient.getClient().create(APIInterface.class);
        Call<ArrayList<Test>> call = apiInterface.getALLData();
        call.enqueue(new Callback<ArrayList<Test>>() {
            @Override
            public void onResponse(Call<ArrayList<Test>> call, Response<ArrayList<Test>> response) {
                arrTest = response.body();
                initRecycler();
            }

            @Override
            public void onFailure(Call<ArrayList<Test>> call, Throwable t) {

            }
        });
    }

    private void initRecycler() {
        recyclerView = (RecyclerView) findViewById(R.id.recyclerView);
        LinearLayoutManager mLayout = new LinearLayoutManager(activity);
        recyclerView.setLayoutManager(mLayout);
        adapter = new MyAdapter(activity, arrTest);
        recyclerView.setAdapter(adapter);
    }
}

Android Firebase User Registration 

• Features of Firebase?

• Go to https://firebase.google.com/
• Click on Get Started for Free.

• Now click on create a new project. 

• Give your app a name and click on create project.

• Now you will see the Firebase Panel. You need to click on Android Icon here.

Step 1: Create a new project and name it ZoomControlsApp.

Step 2: Open res -> layout ->content_main and add following code 
In this step we add the code for displaying a ImageView and ZoomControls.




Add image into drawable folder

tools:showIn="@layout/activity_main">


<TextView   

 android:textAppearance="?android:attr/textAppearanceLarge"

 android:text="Zoom Control Button"

 android:id="@+id/textView2"      

 android:gravity="center"       

 android:layout_alignParentTop="true"      

 android:layout_centerHorizontal="true" />
<ImageView        

android:layout_width="300dp"     

android:layout_height="400dp"       

android:id="@+id/imageView2"        

android:layout_centerHorizontal="true"      

android:layout_marginTop="10dp"       

android:src="@drawable/image"/>

<ZoomControls       

  android:layout_width="wrap_content"     

  android:layout_height="wrap_content"     

  android:id="@+id/zoomControls1"      

  android:layout_below="@id/imageView2"      

  android:layout_centerVertical="true"      

  android:layout_centerHorizontal="true" />

</RelativeLayout>

Step 3: Open Src/Java  -> package -> MainActivity.java

package com.example.mukesh.zoombuttondemo;

import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.widget.ImageView;
import android.widget.ZoomControls;

public class Main1Activity extends AppCompatActivity {
    ZoomControls zoom1;
    ImageView img1;

    @Override    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        zoom1=(ZoomControls)findViewById(R.id.zoomControls1);
        img1=(ImageView)findViewById(R.id.imageView2);

        zoom1.setOnZoomInClickListener(new View.OnClickListener() {
            @Override          

              public void onClick(View v) {
                float x=img1.getScaleX();
                float y=img1.getScaleY();

                img1.setScaleY(x+1);
                img1.setScaleY(y+1);
            }
        });

        zoom1.setOnZoomOutClickListener(new View.OnClickListener() {
            @Override           

              public void onClick(View v) {
                float x=img1.getScaleX();
                float y=img1.getScaleY();
                img1.setScaleY(x-1);
                img1.setScaleY(y-1);
            }
        });

    }

}