<?xml version="1.0" encoding="utf-8"?>

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"

    xmlns:tools="http://schemas.android.com/tools"

    android:layout_width="match_parent"

    android:layout_height="match_parent"

    android:background="#ff0000"

    tools:context="me.chunsheng.hongbao.activities.GallaryActivity">

    <ImageView

        android:id="@+id/displayImage"

        android:layout_width="fill_parent"

        android:layout_height="fill_parent"

        android:layout_weight="1.0" />

    <HorizontalScrollView

        android:layout_width="fill_parent"

        android:layout_height="wrap_content">

        <LinearLayout

            android:id="@+id/mygallery"

            android:layout_width="wrap_content"

            android:layout_height="wrap_content"

            android:orientation="horizontal" />

    </HorizontalScrollView>

</RelativeLayout>

package me.chunsheng.hongbao.activities;

import android.app.Activity;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.support.v7.app.AppCompatActivity;

import android.os.Bundle;

import android.util.Log;

import android.view.View;

import android.view.ViewGroup;

import android.widget.ImageView;

import android.widget.LinearLayout;

import java.io.IOException;

import java.io.InputStream;

import me.chunsheng.hongbao.R;

public class GallaryActivity extends Activity {

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_gallary);

        final ImageView diplayImage = (ImageView) findViewById(R.id.displayImage);

        final LinearLayout myGallery = (LinearLayout) findViewById(R.id.mygallery);

        try {

            String galleryDirectoryName = "gallery";

            String[] listImages = new String[3];

            for (int i = 0; i < 4; i++) {

                //InputStream is = getAssets().open(galleryDirectoryName + "/" + imageName);

                //final Bitmap bitmap = BitmapFactory.decodeStream(is);

                ImageView imageView = new ImageView(getApplicationContext());

                imageView.setLayoutParams(new ViewGroup.LayoutParams(700, 700));

                imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);

                imageView.setImageResource(R.mipmap.mayun);

                imageView.setOnClickListener(new View.OnClickListener() {

                    @Override

                    public void onClick(View view) {

                        diplayImage.setImageResource(R.mipmap.bg_action_bar);

                    }

                });

                myGallery.addView(imageView);

            }

        } catch (Exception e) {

        }

    }

}