导航页面，三张图片后点击进入主页面第一次显示导航再次访问不显示导航页面sharedPreference

最新推荐文章于 2023-10-22 22:41:37 发布

原创最新推荐文章于 2023-10-22 22:41:37 发布 · 1.4k 阅读

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文章标签：

#sharedPreference记住页面 #导航页面滑动到最后一张图片点击进入主页面 #viewpager图片导航

本文介绍了一个使用Android ViewPager实现页面切换的应用示例，并通过按钮显示逻辑与ViewPager联动，达到特定页面展示按钮的效果。示例中还展示了如何通过SharedPreferences保存状态。

布局

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.example.month_lianxi.Main2Activity">
    <android.support.v4.view.ViewPager
        android:id="@+id/m2_vp"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="9"
        >
    </android.support.v4.view.ViewPager>
    <Button
        android:id="@+id/m2_btn"
        android:layout_width="wrap_content"
        android:layout_height="0dp"
        android:layout_gravity="center"
        android:visibility="invisible"
        android:layout_weight="1"
        android:text="点击进入"/>

</LinearLayout>

代码

public class Main2Activity extends AppCompatActivity {

    private ViewPager viewPager;
    private Button button;
    private SharedPreferences sp;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main2);
        viewPager = (ViewPager) findViewById(R.id.m2_vp);
        button = (Button) findViewById(R.id.m2_btn);

        sp = getSharedPreferences("mydata", MODE_PRIVATE);
        boolean zj = sp.getBoolean("zj", false);
        if (zj){
            Intent intent=new Intent(Main2Activity.this,Main3Activity.class);
            startActivity(intent);
        }

        getconn();
        viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {

            }

            @Override
            public void onPageSelected(int position) {
                if (position==2){
                    SharedPreferences.Editor edit = sp.edit();
                    edit.putBoolean("zj",true);
                    edit.commit();
                    button.setVisibility(View.VISIBLE);
                }else{
                    button.setVisibility(View.INVISIBLE);
                }
            }

            @Override
            public void onPageScrollStateChanged(int state) {

            }
        });

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Intent intent=new Intent(Main2Activity.this,Main3Activity.class);
                startActivity(intent);
            }
        });

    }

    private void getconn() {
        String path="http://www.yulin520.com/a2a/impressApi/news/mergeList?pageSize=3&page=1";
        NetConnection.getconnection(Main2Activity.this, path, new CallJsonBack() {
            @Override
            public void getcallBack(String json) {
                if (json!=null){
                    Gson gson=new Gson();
                    DaoHangBean daoHangBean = gson.fromJson(json, DaoHangBean.class);
                    List<DaoHangBean.DataBean> data = daoHangBean.getData();
                    DHadapter hadapter=new DHadapter(data,Main2Activity.this);
                    viewPager.setAdapter(hadapter);

                }

            }
        });
    }


}