login界面，判断是否是最后一个图片，如果不是则隐藏，是则显示

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

<RadioGroup
android:id="@+id/radiogroup"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_marginBottom="70dp"
android:gravity="center"
android:orientation="horizontal" >

<RadioButton
android:id="@+id/radio_1"
android:layout_width="wrap_content"
android:checked="true"
android:layout_height="wrap_content" />

<RadioButton
android:id="@+id/radio_2"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<RadioButton
android:id="@+id/radio_3"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

<RadioButton
android:id="@+id/radio_4"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RadioGroup>

<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="20dp"
android:gravity="center"
android:id="@+id/tiyan"
android:visibility="gone"
android:text="开始体验" />

</RelativeLayout>

package yaozhipu.bwei.com.month2;

import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.RadioGroup;

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

import yaozhipu.bwei.com.month2.adapter.ViewPagerAdapter;

public class Main3Activity extends AppCompatActivity {

private ViewPager pager;
private RadioGroup group;
private Button button;
private List<Integer> list;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main3);

pager = (ViewPager) findViewById(R.id.viewpager);
group = (RadioGroup) findViewById(R.id.radiogroup);
button = (Button) findViewById(R.id.tiyan);

list = new ArrayList<Integer>();
list.add(R.drawable.a1);
list.add(R.drawable.a2);
list.add(R.drawable.a3);
list.add(R.drawable.a4);

ViewPagerAdapter adapter = new ViewPagerAdapter(Main3Activity.this, list);
pager.setAdapter(adapter);

pager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {

@Override
public void onPageSelected(int position) {
// TODO Auto-generated method stub
group.check(group.getChildAt(position).getId());
if (position==list.size()-1) {
button.setVisibility(View.VISIBLE);
button.setOnClickListener(new View.OnClickListener() {

@Override
public void onClick(View v) {
// TODO Auto-generated method stub
//跳转
Intent intent = new Intent(Main3Activity.this, Main2Activity.class);

b9fb
startActivity(intent);
finish();

}
});
}else {
button.setVisibility(View.GONE);
}
}

@Override
public void onPageScrolled(int position, float positionOffset,
int positionOffsetPixels) {
// TODO Auto-generated method stub

}

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

}
});

group.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {

@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
// TODO Auto-generated method stub
switch (checkedId) {
case R.id.radio_1:
pager.setCurrentItem(0, false);
break;
case R.id.radio_2:
pager.setCurrentItem(1, false);
break;
case R.id.radio_3:
pager.setCurrentItem(2, false);
break;
case R.id.radio_4:
pager.setCurrentItem(3, false);
break;

default:
break;
}
}
});

}
}