ViewPager 首次安装软件加载图片介绍并判断是否第一次,如果第一次展示图片,否则直接进入软件

XML文件为简单的ListView和展示的XML文件为简单的ImageView


package com.example.mothtree_day1_r;

import java.util.ArrayList;
import java.util.List;

import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.view.ViewPager.OnPageChangeListener;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;

public class MainActivity extends Activity {
    ViewPager pager;
    Button btn;
    View view1, view2, view3;
    List<View> list;
    Boolean flag;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        pager = (ViewPager) findViewById(R.id.pager);
        btn = (Button) findViewById(R.id.but);
        btn.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub
                Intent intent = new Intent(MainActivity.this, MyActivity.class);
                startActivity(intent);
            }
        });
        SharedPreferences shared = getSharedPreferences("text",
                Activity.MODE_PRIVATE);
        flag = shared.getBoolean("bool", false);
        guite();
        list = new ArrayList<View>();
        LayoutInflater lf = LayoutInflater.from(this);
        view1 = lf.inflate(R.layout.pager1, null);
        view2 = lf.inflate(R.layout.pager2, null);
        view3 = lf.inflate(R.layout.pager3, null);
        list.add(view1);
        list.add(view2);
        list.add(view3);
        pager.setAdapter(new myadapter());
        pager.setOnPageChangeListener(new OnPageChangeListener() {
            @Override
            public void onPageSelected(int arg0) {
                if (arg0 == 2) {
                    btn.setVisibility(View.VISIBLE);
                } else {
                    btn.setVisibility(View.INVISIBLE);
                }
            }

            @Override
            public void onPageScrolled(int arg0, float arg1, int arg2) {
                // TODO Auto-generated method stub

            }

            @Override
            public void onPageScrollStateChanged(int arg0) {
                // TODO Auto-generated method stub

            }
        });

    }

    private void guite() {
        if (!flag) {
            SharedPreferences shared = getSharedPreferences("text",
                    Activity.MODE_PRIVATE);
            SharedPreferences.Editor editor = shared.edit();
            editor.putBoolean("bool", true);
            editor.commit();
            pager.setVisibility(View.VISIBLE);
        } else {
            pager.setVisibility(View.INVISIBLE);
            Intent intent = new Intent(MainActivity.this, MyActivity.class);
            startActivity(intent);
        }
    }

    class myadapter extends PagerAdapter {

        @Override
        public int getCount() {
            // TODO Auto-generated method stub
            return list.size();
        }

        @Override
        public boolean isViewFromObject(View arg0, Object arg1) {
            // TODO Auto-generated method stub
            return arg0 == arg1;
        }

        @Override
        public void destroyItem(ViewGroup container, int position, Object object) {
            // TODO Auto-generated method stub
            container.removeView(list.get(position));
        }

        @Override
        public Object instantiateItem(ViewGroup container, int position) {
            // TODO Auto-generated method stub
            container.addView(list.get(position));
            return list.get(position);
        }

    }
}