滑块开始第二页

Question

我已经在本教程中的滑块（https://www.androidhive.info/2016/05/android-build-intro-slider-app/）：

package com.example.user.slider; 

import android.content.Context; 
import android.content.Intent; 
import android.graphics.Color; 
import android.os.Build; 
import android.os.Bundle; 
import android.support.v4.view.PagerAdapter; 
import android.support.v4.view.ViewPager; 
import android.support.v7.app.AppCompatActivity; 
import android.text.Html; 
import android.view.LayoutInflater; 
import android.view.View; 
import android.view.ViewGroup; 
import android.view.Window; 
import android.view.WindowManager; 
import android.widget.ImageButton; 
import android.widget.ImageView; 
import android.widget.LinearLayout; 
import android.widget.TextView; 

public class WelcomeActivity extends AppCompatActivity { 

    private ViewPager viewPager; 
    private MyViewPagerAdapter myViewPagerAdapter; 
    private LinearLayout dotsLayout; 
    private TextView[] dots; 
    private int[] layouts; 
    private ImageButton btnNotes, btnSettings; 
    private ImageView bldNotes, bldSettings; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     // Making notification bar transparent 
     if (Build.VERSION.SDK_INT >= 21) { 
      getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LAYOUT_STABLE | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN); 
     } 

     setContentView(R.layout.activity_welcome); 

     viewPager = (ViewPager) findViewById(R.id.view_pager); 
     dotsLayout = (LinearLayout) findViewById(R.id.layoutDots); 
     btnNotes = (ImageButton) findViewById(R.id.btn_notes); 
     btnSettings = (ImageButton) findViewById(R.id.btn_settings); 
     bldNotes = (ImageView) findViewById(R.id.bld_notes); 
     bldSettings = (ImageView) findViewById(R.id.bld_settings); 

     btnSettings.setVisibility(View.GONE); 
     btnNotes.setVisibility(View.VISIBLE); 


     // layouts of all welcome sliders 
     // add few more layouts if you want 
     layouts = new int[]{ 
       R.layout.welcome_slide1, 
       R.layout.welcome_slide2, 
       R.layout.welcome_slide3}; 

     // adding bottom dots 
     addBottomDots(0); 

     // making notification bar transparent 
     changeStatusBarColor(); 

     myViewPagerAdapter = new MyViewPagerAdapter(); 
     viewPager.setAdapter(myViewPagerAdapter); 
     viewPager.addOnPageChangeListener(viewPagerPageChangeListener); 


     btnNotes.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       startActivity(new Intent(WelcomeActivity.this, MainActivity.class)); 
      } 
     }); 

     btnSettings.setOnClickListener(new View.OnClickListener() { 
      @Override 
      public void onClick(View v) { 
       startActivity(new Intent(WelcomeActivity.this, MainActivity.class)); 
      } 
     }); 
    } 

    private void addBottomDots(int currentPage) { 
     dots = new TextView[layouts.length]; 

     int[] colorsActive = getResources().getIntArray(R.array.array_dot_active); 
     int[] colorsInactive = getResources().getIntArray(R.array.array_dot_inactive); 

     dotsLayout.removeAllViews(); 
     for (int i = 0; i < dots.length; i++) { 
      dots[i] = new TextView(this); 
      dots[i].setText(Html.fromHtml("&#8226;")); 
      dots[i].setTextSize(35); 
      dots[i].setTextColor(colorsInactive[currentPage]); 
      dotsLayout.addView(dots[i]); 
     } 

     if (dots.length > 0) 
      dots[currentPage].setTextColor(colorsActive[currentPage]); 
    } 

    private int getItem(int i) { 
     return viewPager.getCurrentItem() + i; 
    } 

    // viewpager change listener 
    ViewPager.OnPageChangeListener viewPagerPageChangeListener = new ViewPager.OnPageChangeListener() { 

     @Override 
     public void onPageSelected(int position) { 
      addBottomDots(position); 

      // changing the next button text 'NEXT'/'GOT IT' 
      if (position == 0) { 
       btnSettings.setVisibility(View.GONE); 
       btnNotes.setVisibility(View.VISIBLE); 
      } else if (position == 1) { 
       btnSettings.setVisibility(View.GONE); 
       btnNotes.setVisibility(View.GONE); 
      } else if (position == 2) { 
       btnSettings.setVisibility(View.VISIBLE); 
       btnNotes.setVisibility(View.GONE); 
      } 
     } 

     @Override 
     public void onPageScrolled(int arg0, float arg1, int arg2) { 

     } 

     @Override 
     public void onPageScrollStateChanged(int arg0) { 

     } 
    }; 

    /** 
    * Making notification bar transparent 
    */ 
    private void changeStatusBarColor() { 
     if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) { 
      Window window = getWindow(); 
      window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS); 
      window.setStatusBarColor(Color.TRANSPARENT); 
     } 
    } 

    /** 
    * View pager adapter 
    */ 
    public class MyViewPagerAdapter extends PagerAdapter { 
     private LayoutInflater layoutInflater; 

     public MyViewPagerAdapter() { 
     } 

     @Override 
     public Object instantiateItem(ViewGroup container, int position) { 
      layoutInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE); 
      View view = null; 

      view = layoutInflater.inflate(layouts[position], container, false); 
      container.addView(view); 

      return view; 
     } 

     @Override 
     public int getCount() { 
      return layouts.length; 
     } 

     @Override 
     public boolean isViewFromObject(View view, Object obj) { 
      return view == obj; 
     } 


     @Override 
     public void destroyItem(ViewGroup container, int position, Object object) { 
      View view = (View) object; 
      container.removeView(view); 
     } 
    } 
} 

我的问题是，滑块与第一页/布局开始，但我想，滑块开始与第二页。有人能帮助我吗？

随着最佳的愿望， 的裨

Answer 1

使用视图寻呼机setCurrentItem();方法来设置viewpager现在的位置这样

myViewPagerAdapter = new MyViewPagerAdapter(); 
viewPager.setAdapter(myViewPagerAdapter);    
viewPager.addOnPageChangeListener(viewPagerPageChangeListener); 
viewPager.setCurrentItem(0);// set postion as per your requirement