Android实现实时滑动ViewPager的2种方式

<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" 
 tools:context="com.example.welcome.mainactivity" > 
 
 <android.support.v4.view.viewpager 
 android:id="@+id/mviewpager" 
 android:layout_width="fill_parent" 
 android:layout_height="fill_parent" /> 
 
 <framelayout 
 android:layout_width="fill_parent" 
 android:layout_height="wrap_content" 
 android:layout_alignparenttop="true" 
 android:layout_centerhorizontal="true" 
 android:layout_margintop="30dp" > 
 
 <com.example.welcome.pagercursor 
  android:id="@+id/pagercursor" 
  android:layout_width="fill_parent" 
  android:layout_height="5dp" /> 
 </framelayout> 
 
 <framelayout 
 android:layout_width="wrap_content" 
 android:layout_height="wrap_content" 
 android:layout_alignparentbottom="true" 
 android:layout_centerhorizontal="true" 
 android:layout_marginbottom="30dp" > 
 
 <com.example.welcome.customedotgroup 
  android:id="@+id/ll_point_group" 
  android:layout_width="fill_parent" 
  android:layout_height="10dp" 
  android:orientation="horizontal" > 
 </com.example.welcome.customedotgroup> 
 
 <view 
  android:id="@+id/red_point" 
  android:layout_width="10dp" 
  android:layout_height="10dp" 
  android:background="@drawable/point_red" /> 
 </framelayout> 
 
</relativelayout> 

package com.example.welcome; 
 
import java.util.arraylist; 
 
import android.app.activity; 
import android.os.bundle; 
import android.support.v4.view.pageradapter; 
import android.support.v4.view.viewpager; 
import android.support.v4.view.viewpager.onpagechangelistener; 
import android.view.view; 
import android.view.viewgroup; 
import android.view.animation.translateanimation; 
import android.widget.imageview; 
 
public class mainactivity extends activity { 
 private viewpager mviewpager; 
 
 myadapter madapter; 
 private arraylist<imageview> imageviewlist; 
 view red_point; 
 private int lastdis; 
 pagercursor pagercursor; 
 @suppresswarnings("deprecation") 
 @override 
 protected void oncreate(bundle savedinstancestate) { 
 super.oncreate(savedinstancestate); 
 setcontentview(r.layout.activity_main); 
 pagercursor = (pagercursor) findviewbyid(r.id.pagercursor); 
 red_point = findviewbyid(r.id.red_point); 
 imageviewlist = new arraylist<imageview>(); 
 int[] imagesint = {r.drawable.p1,r.drawable.p2,r.drawable.p3}; 
 for (int i = 0; i < imagesint.length; i++) { 
  imageview imageview = new imageview(mainactivity.this); 
  imageview.setbackgroundresource(imagesint[i]); 
  imageviewlist.add(imageview); 
  
 } 
 mviewpager = (viewpager) findviewbyid(r.id.mviewpager); 
  
 madapter = new myadapter(); 
  
 mviewpager.setadapter(madapter); 
  
 mviewpager.setonpagechangelistener(new onpagechangelistener() { 
  
  private boolean isdragging; 
  
 
  @override 
  public void onpageselected(int arg0) { 
   
  } 
  
  @override 
  public void onpagescrolled(int position, float screenoffset, int arg2) { 
  translateanimation animation = null; 
  if (isdragging) { 
   
   int dp2px = phoneutils.dp2px(mainactivity.this, 20f); 
   int offset = (int) (position*dp2px + dp2px*screenoffset); 
   
   animation = new translateanimation(lastdis, offset, 0f, 0f); 
   animation.setduration(200); 
   animation.setfillafter(true); 
   red_point.startanimation(animation); 
   
   lastdis = offset; 
   
   
   
  } 
  float[] screensize = measureutil.getscreensize(mainactivity.this); 
  float itemwidth = screensize[0]/3; 
   
  pagercursor.setoffset(position,screenoffset,itemwidth); 
   
  } 
  
  @override 
  public void onpagescrollstatechanged(int arg0) { 
  switch (arg0) { 
  case viewpager.scroll_state_dragging://滑动 
   isdragging = true; 
   break; 
  case viewpager.scroll_state_idle://空闲 
   isdragging = false; 
   break; 
 
  default: 
   break; 
  } 
  } 
 }); 
 } 
 
 
 class myadapter extends pageradapter{ 
 
 @override 
 public int getcount() { 
  return imageviewlist.size(); 
 } 
 
 @override 
 public boolean isviewfromobject(view arg0, object arg1) { 
  return arg0 == arg1; 
 } 
  
 @override 
 public void destroyitem(viewgroup container, int position, object object) { 
  container.removeview(imageviewlist.get(position)); 
 } 
  
 @override 
 public object instantiateitem(viewgroup container, int position) { 
  container.addview(imageviewlist.get(position)); 
  return imageviewlist.get(position); 
 } 
  
 } 
} 

package com.example.welcome; 
import android.content.context; 
import android.util.attributeset; 
import android.view.view; 
import android.widget.imageview; 
import android.widget.linearlayout; 
 
public class customedotgroup extends linearlayout { 
 
 private context context; 
 public customedotgroup(context context, attributeset attrs, int defstyle) { 
 super(context, attrs, defstyle); 
 this.context = context; 
 initres(); 
 } 
 
 public customedotgroup(context context, attributeset attrs) { 
 this(context, attrs, 0); 
 } 
 
 public customedotgroup(context context) { 
 this(context, null); 
 } 
 
 
 
 private void initres() { 
 int dotwidthorheight = phoneutils.dp2px(context, 10); 
  
 for (int i = 0; i < 3; i++) { 
  imageview dotimageview = new imageview(context); 
  dotimageview.setbackgroundresource(r.drawable.point_normal); 
  
  layoutparams dotimageviewparams = new layoutparams(dotwidthorheight, dotwidthorheight); 
  if (i != 0) { 
  dotimageviewparams.leftmargin = dotwidthorheight; 
  } 
  dotimageview.setlayoutparams(dotimageviewparams); 
  this.addview(dotimageview); 
 } 
  
 } 
 
}

package com.example.welcome; 
 
import android.app.activity; 
import android.content.context; 
import android.graphics.canvas; 
import android.graphics.paint; 
import android.util.attributeset; 
import android.util.log; 
import android.view.view; 
 
public class pagercursor extends view { 
 context context; 
 private paint mpaint; 
 private int screenwidth; 
 private int desright; 
 private float itemwidth; 
 
 public pagercursor(context context, attributeset attrs, int defstyle) { 
 super(context, attrs, defstyle); 
 // todo auto-generated constructor stub 
 } 
 
 public pagercursor(context context, attributeset attrs) { 
 super(context, attrs); 
 this.context = context; 
 initres(); 
 // todo auto-generated constructor stub 
 } 
 
 public pagercursor(context context) { 
 super(context); 
 // todo auto-generated constructor stub 
 } 
 
 private void initres() { 
 float[] screensize = measureutil.getscreensize((activity) context); 
 screenwidth = (int) screensize[0]; 
 log.d("tag", ",screenwidth" + screenwidth); 
 
 mpaint = new paint(); 
 mpaint.setcolor(getresources().getcolor(r.color.contentpresscolor)); 
 mpaint.setstyle(paint.style.fill); 
 mpaint.setantialias(true); 
 } 
 
 public void setoffset(int position, float screenoffset, float itemwidth) { 
 int offset = (int) (position * itemwidth + itemwidth * screenoffset); 
 this.itemwidth = itemwidth; 
 desright = offset; 
 log.d("tag", "screenoffset:" + screenoffset + ",position" + position 
  + ",desrigh-->t" + desright + ",itemwidth" + itemwidth); 
 
 invalidate(); 
 } 
 
 @override 
 protected void ondraw(canvas canvas) { 
 super.ondraw(canvas); 
 log.d("tag", "ondraw,desrigh-->t" + desright + ",itemwidth" + itemwidth); 
 canvas.drawrect(desright, 0f, desright + itemwidth, 
  phoneutils.dp2px(context, 5), mpaint); 
 } 
} 

package com.example.welcome; 
 
import android.app.activity; 
import android.util.displaymetrics; 
 
/** 
 * 测绘工具�? 
 */ 
public final class measureutil { 
 /** 
 * 获取屏幕尺寸 
 * 
 * @param activity 
 *  activity 
 * @return 屏幕尺寸像素值，下标�?的�?为宽，下标为1的�?为高 
 */ 
 public static float[] getscreensize(activity activity) { 
 displaymetrics metrics = new displaymetrics(); 
 activity.getwindowmanager().getdefaultdisplay().getmetrics(metrics); 
 return new float[] { metrics.widthpixels, metrics.heightpixels }; 
 } 
} 

package com.example.welcome; 
 
import android.content.context; 
 
public class phoneutils { 
 
 public static int dp2px(context context,float dpvalue){ 
 float scale = context.getresources().getdisplaymetrics().density; 
 return (int)(dpvalue * scale +0.5f); 
 } 
}