[JAVA][Android] 이미지 넘겨보기

이미지 넘겨보기 예제를 해보겠습니다.

 

1. manifests 추가

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

2. build.gradle 추가

    // ViewPager2
    implementation "androidx.viewpager2:viewpager2:1.0.0"

    // Glide
    implementation 'com.github.bumptech.glide:glide:4.9.0'
    annotationProcessor 'com.github.bumptech.glide:compiler:4.9.0'

3. res - layout - item_silder.xml 생성

<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/imageSlider"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:contentDescription="@string/app_name"
    android:scaleType="centerCrop" />

4. res - layout - ibg_fading_edge.xml 생성 : 이미지 모아보기 할 때 하단에 색상 넣어줄려고

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle">

    <gradient
        android:angle="270"
        android:startColor="@android:color/transparent"
        android:endColor="#111111" />

</shape>

5.  res - layout - bg_indicator_active.xml 생성 : 선택된 이미지는 다른색상으로 표시해 주려고

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">

    <size
        android:width="12dp"
        android:height="12dp" />

    <solid
        android:color="#6200EE" />

</shape>

 

6.  res - layout - bg_indicator_inactive.xml 생성 

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">

    <size
        android:width="8dp"
        android:height="8dp" />

    <solid
        android:color="#eeeeee" />

</shape>

7. activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.viewpager2.widget.ViewPager2
        android:id="@+id/sliderViewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent" />

    <View
        android:id="@+id/viewFadingEdge"
        android:layout_width="match_parent"
        android:layout_height="55dp"
        android:background="@drawable/bg_fading_edge"
        app:layout_constraintBottom_toBottomOf="@id/sliderViewPager" />

    <LinearLayout
        android:id="@+id/layoutIndicators"
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:gravity="center"
        android:paddingBottom="8dp"
        app:layout_constraintBottom_toBottomOf="@id/viewFadingEdge"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

8. MainActivity.java

import androidx.appcompat.app.AppCompatActivity;
import androidx.core.content.ContextCompat;
import androidx.viewpager2.widget.ViewPager2;

import android.os.Bundle;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.LinearLayout;

public class MainActivity extends AppCompatActivity {

    private ViewPager2 sliderViewPager;
    private LinearLayout layoutIndicator;

    private String[] images = new String[] {
            "https://cdn.pixabay.com/photo/2019/12/26/10/44/horse-4720178_1280.jpg",
            "https://cdn.pixabay.com/photo/2020/11/04/15/29/coffee-beans-5712780_1280.jpg",
            "https://cdn.pixabay.com/photo/2020/03/08/21/41/landscape-4913841_1280.jpg",
            "https://cdn.pixabay.com/photo/2020/09/02/18/03/girl-5539094_1280.jpg",
            "https://cdn.pixabay.com/photo/2014/03/03/16/15/mosque-279015_1280.jpg"
    };

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

        sliderViewPager = findViewById(R.id.sliderViewPager);
        layoutIndicator = findViewById(R.id.layoutIndicators);

        // viewpager를 사용할 때 이전 혹은 다음페이지를 몇개까지 미리 로딩할지 정하는 함수
        sliderViewPager.setOffscreenPageLimit(1);
        sliderViewPager.setAdapter(new ImageSliderAdapter(this, images));
        sliderViewPager.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
            @Override
            public void onPageSelected(int position) {
                super.onPageSelected(position);
                setCurrentIndicator(position);
            }
        });

        setupIndicators(images.length);
    }

    // 사진의 숫자만큼 동그란 점 만들기
    private void setupIndicators(int count) {
        ImageView[] indicators = new ImageView[count];
        LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(
                ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);

        params.setMargins(16, 8, 16, 8);

        for (int i = 0; i < indicators.length; i++) {
            indicators[i] = new ImageView(this);
            indicators[i].setImageDrawable(ContextCompat.getDrawable(this,
                    R.drawable.bg_indicator_inactive));
            indicators[i].setLayoutParams(params);
            layoutIndicator.addView(indicators[i]);
        }
        setCurrentIndicator(0);
    }

    //  선택된 페이지 색상 다르게 하기
    private void setCurrentIndicator(int position) {
        int childCount = layoutIndicator.getChildCount();
        for (int i = 0; i < childCount; i++) {
            ImageView imageView = (ImageView) layoutIndicator.getChildAt(i);
            if (i == position) {
                imageView.setImageDrawable(ContextCompat.getDrawable(
                        this,
                        R.drawable.bg_indicator_active
                ));
            } else {
                imageView.setImageDrawable(ContextCompat.getDrawable(
                        this,
                        R.drawable.bg_indicator_inactive
                ));
            }
        }
    }
}

9. ImageSliderAdapter.java

import android.content.Context;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;

import com.bumptech.glide.Glide;

public class ImageSliderAdapter extends RecyclerView.Adapter<ImageSliderAdapter.MyViewHolder> {
    private Context context;
    private String[] sliderImage;

    public ImageSliderAdapter(Context context, String[] sliderImage) {
        this.context = context;
        this.sliderImage = sliderImage;
    }

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

    @Override
    public void onBindViewHolder(@NonNull MyViewHolder holder, int position) {
        holder.bindSliderImage(sliderImage[position]);
    }

    @Override
    public int getItemCount() {
        return sliderImage.length;
    }

    public class MyViewHolder extends RecyclerView.ViewHolder {

        private ImageView mImageView;

        public MyViewHolder(@NonNull View itemView) {
            super(itemView);
            mImageView = itemView.findViewById(R.id.imageSlider);
        }

        public void bindSliderImage(String imageURL) {
            Glide.with(context)
                    .load(imageURL)
                    .into(mImageView);
        }
    }
}

참고한사이트

https://android-dev.tistory.com/12

[Android/Java] 안드로이드 ViewPager2 이미지 슬라이드 만들기