ViewPage加小圓點

package com.example.mypandatv;

import android.content.Intent;
import android.content.SharedPreferences;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.LinearLayout;

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

public class GuideActivity extends AppCompatActivity implements View.OnClickListener{

    private ViewPager vp;
    private LinearLayout line;
    private Button btn;
    private int [] imgarr = {R.drawable.guide_one,R.drawable.guide_two,R.drawable.guide_three};
    private List<ImageView> initimage;
    private List<ImageView> initdot;

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

        SharedPreferences baocui = getSharedPreferences("baocui",0);
        int anInt = baocui.getInt("int", 0);
        if(anInt!=0){
            Intent intent=new Intent(GuideActivity.this,MainActivity.class);
            startActivity(intent);
        }

        initView();

        initData();

        initAdapter();

        initListener();
    }

    private void initListener() {
        vp.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                for (int i = 0; i < 3; i++) {
                    if (position==i){
                        initdot.get(i).setImageResource(R.drawable.guide_selectshape);
                    }else{
                        initdot.get(i).setImageResource(R.drawable.guide_noselectshape);
                    }

                    if(position==initimage.size()-1){
                        line.setVisibility(View.GONE);
                        btn.setVisibility(View.VISIBLE);
                    }else{
                        line.setVisibility(View.VISIBLE);
                        btn.setVisibility(View.GONE);
                    }

                }

            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });
    }

    private void initAdapter() {
        MyGuideAdapter adapter = new MyGuideAdapter(initimage);
        vp.setCurrentItem(0);
        vp.setAdapter(adapter);
    }

    private void initData() {
        initimage = new ArrayList<>();
        for (int i = 0; i < 3; i++) {
            ImageView imageView = new ImageView(this);
            imageView.setImageResource(imgarr[i]);
            initimage.add(imageView);
        }

        initdot = new ArrayList<>();
        for (int i = 0; i < 4; i++) {
            ImageView imageView = new ImageView(this);
            LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
            layoutParams.leftMargin = 10;
            layoutParams.rightMargin = 10;
            layoutParams.width = 18;
            layoutParams.height = 18;
            if(i==0){
                imageView.setImageResource(R.drawable.guide_selectshape);
            }else{
                imageView.setImageResource(R.drawable.guide_noselectshape);
            }
            line.addView(imageView,layoutParams);
            initdot.add(imageView);
        }


    }

    private void initView() {
        vp = (ViewPager) findViewById(R.id.guide_vp);
        line = (LinearLayout) findViewById(R.id.guide_line);
        btn = (Button) findViewById(R.id.guide_btn);

        btn.setOnClickListener(this);
    }

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
            case R.id.guide_btn:

                SharedPreferences baocui = getSharedPreferences("baocui", 0);
                SharedPreferences.Editor edit = baocui.edit();
                edit.putInt("int",-100);

                edit.commit();


                Intent intent = new Intent(GuideActivity.this,MainActivity.class);
                startActivity(intent);

                break;
        }
    }
}