引导页跳转界面

package wss.com.yuekaolianxi_02;

import android.content.Context;
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.widget.Button;
import android.widget.ImageView;
import android.widget.RadioButton;
import android.widget.RadioGroup;

import java.util.ArrayList;

import wss.com.yuekaolianxi_02.adapter.MyViewPaerAdapter;

public class MainActivity extends AppCompatActivity {

private ViewPager mainViewpager;
private RadioGroup mainRadiogroup;
private Button mainButton;
private ArrayList<ImageView> list;

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


    //获取资源id
    mainViewpager = (ViewPager) findViewById(R.id.main_viewpager);
    mainRadiogroup = (RadioGroup) findViewById(R.id.main_radiogroup);
    mainButton = (Button) findViewById(R.id.main_button);


    //设置点击button按钮跳转
    mainButton.set Listener(new View. Listener() {
        @Override
        public void  (View v) {
            startActivity(new Intent(MainActivity.this,HomeActivity.class));
        }
    });

    //获取sp
    SharedPreferences sp = getSharedPreferences(\"引导页\",Context.MODE_PRIVATE);
    if (sp.getBoolean(\"key\",false)) {
        startActivity(new Intent(MainActivity.this,HomeActivity.class));
        finish();
        return;
    }
    sp.edit().putBoolean(\"key\",true).commit();
    //创建数组
    int arr[]={
        R.drawable.ydy01,
        R.drawable.ydy02,
        R.drawable.ydy03,
        R.drawable.ydy04,
    };
    //创建集合
    list = new ArrayList<>();
    //添加图片,小圆点
    for (int i = 0; i < arr.length; i++) {
        ImageView imageView = new ImageView(MainActivity.this);
        imageView.setImageResource(arr[i]);
        list.add(imageView);

        RadioButton button = new RadioButton(MainActivity.this);
        mainRadiogroup.addView(button);
    }
    //默认小圆点
    mainRadiogroup.check(mainRadiogroup.getChildAt(0).getId());

    //设置适配器
    mainViewpager.setAdapter(new MyViewPaerAdapter(MainActivity.this,list));
    //设置监听
    mainViewpager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
        @Override
        public void onPageScrolled(int i, float v, int i1) {
            if (i==list.size()-1) {
                mainButton.setVisibility(View.VISIBLE);
            }else{
                mainButton.setVisibility(View.GONE);
            }
        }
        @Override
        public void onPageSelected(int i) {
            mainRadiogroup.check(mainRadiogroup.getChildAt(i).getId());
        }
        @Override
        public void onPageScrollStateChanged(int i) {
        }
    });
}

}
布局代码

<?  version=\"1.0\" encoding=\"utf-8\"?>
<RelativeLayout  ns:android=\"http://schemas.android.com/apk/res/android\"
     ns:app=\"http://schemas.android.com/apk/res-auto\"
     ns:tools=\"http://schemas.android.com/tools\"
    android:layout_width=\"match_parent\"
    android:layout_height=\"match_parent\"
    tools:context=\".MainActivity\">

    <android.support.v4.view.ViewPager
        android:id=\"@+id/main_viewpager\"
        android:layout_width=\"match_parent\"
        android:layout_height=\"match_parent\"/>

    <RadioGroup
        android:id=\"@+id/main_radiogroup\"
        android:layout_width=\"match_parent\"
        android:layout_height=\"50dp\"
        android:layout_alignParentStart=\"true\"
        android:layout_alignParentBottom=\"true\"
        android:gravity=\"center\"
        android:orientation=\"horizontal\"
        android:layout_alignParentLeft=\"true\" />

    <Button
        android:id=\"@+id/main_button\"
        android:layout_width=\"wrap_content\"
        android:layout_height=\"wrap_content\"
        android:layout_alignParentBottom=\"true\"
        android:layout_centerHorizontal=\"true\"
        android:layout_marginBottom=\"73dp\"
        android:text=\"立即进入\" />
</RelativeLayout>