Android仿IOS ViewPager滑动进度条

最近做项目，碰到如下的需求：viewpager分页，如果是6页(包括6页)就用圆点，如果是6页以上就用进度条来切换。前面一种交互方法最常见，用小圆点来表示当前选中的页面，这些小圆点称为导航点，很多app都是这种实现方式。当用户第一次安装或升级应用时，都会利用导航页面告诉用户当前版本的主要亮点，一般情况下当行页面有三部分组成，背景图片，导航文字和滑动的原点，即下面的效果：

这里就不作详细的讲解，大家可以参考我以前写过的博客：
viewpager实现图片轮翻效果
今天来实现viewpager进度条切换，主要逻辑如下：
mainactivity.java

package com.jackie.slidebarviewdemo.activity; 
 
import android.os.bundle; 
import android.support.v7.app.appcompatactivity; 
import android.widget.textview; 
 
import com.jackie.slidebarviewdemo.r; 
import com.jackie.slidebarviewdemo.widget.slidebarview; 
 
public class mainactivity extends appcompatactivity { 
  private slidebarview mslidebarview; 
  private textview mtextview; 
 
  @override 
  protected void oncreate(bundle savedinstancestate) { 
    super.oncreate(savedinstancestate); 
    setcontentview(r.layout.activity_main); 
 
    mslidebarview = (slidebarview) findviewbyid(r.id.slide_bar); 
    mtextview = (textview) findviewbyid(r.id.text_view); 
 
    mslidebarview.settotalpage(80); 
    mslidebarview.setonslidechangelistener(new slidebarview.onslidechangelistener() { 
      @override 
      public void onslidechange(int page) { 
        mtextview.settext("当前是第" + page + "页"); 
      } 
    }); 
  } 
} 

slidebarview.java

package com.jackie.slidebarviewdemo.widget; 
 
import android.content.context; 
import android.util.attributeset; 
import android.view.layoutinflater; 
import android.view.motionevent; 
import android.view.view; 
import android.widget.linearlayout; 
import android.widget.popupwindow; 
import android.widget.relativelayout; 
import android.widget.textview; 
 
import com.jackie.slidebarviewdemo.r; 
import com.jackie.slidebarviewdemo.utils.convertutils; 
 
/** 
 * created by jackie on 2017/1/17. 
 */ 
 
public class slidebarview extends relativelayout { 
  private layoutinflater minflater; 
 
  private relativelayout mslidebarview; 
  private view mslidebarblock; 
 
  private popupwindow mpopupwindow; 
  private textview mpopuptext; 
 
  private int mdp40; 
 
  private string mbound = "no"; // no表示没到边界，left为到左边界了，right表示到右边界了 
 
  public interface onslidechangelistener { 
    void onslidechange(int page); 
  } 
 
  private onslidechangelistener monslidechangelistener; 
  public void setonslidechangelistener(onslidechangelistener onslidechangelistener) { 
    this.monslidechangelistener = onslidechangelistener; 
  } 
 
  public slidebarview(context context) { 
    this(context, null); 
  } 
 
  public slidebarview(context context, attributeset attrs) { 
    this(context, attrs, 0); 
  } 
 
  public slidebarview(context context, attributeset attrs, int defstyleattr) { 
    super(context, attrs, defstyleattr); 
 
    init(context); 
    initevent(); 
  } 
 
  private void init(context context) { 
    minflater = layoutinflater.from(context); 
    view slidebar = minflater.inflate(r.layout.slide_bar, null); 
    layoutparams params = new layoutparams(layoutparams.match_parent, layoutparams.match_parent); 
    addview(slidebar, params); 
 
    mslidebarview = (relativelayout) slidebar.findviewbyid(r.id.slide_bar_view); 
    mslidebarblock = slidebar.findviewbyid(r.id.slide_bar_block); 
 
    mdp40 = convertutils.dip2px(context, 40); 
  } 
 
  private void initevent() { 
    mslidebarview.setontouchlistener(new ontouchlistener() { 
      int currentx = 0; 
      int startx = 0; 
 
      @override 
      public boolean ontouch(view v, motionevent event) { 
        switch (event.getaction()) { 
          case motionevent.action_down: 
            currentx = (int) event.getx(); 
            startx = (int) event.getx(); 
 
            // 设置滑块的滑动, 手指第一次点下去把滑块放到手指上 
            int downleft = currentx - mslidebarblock.getmeasuredwidth() / 2; 
            int downtop = mslidebarblock.gettop(); 
            int downright = downleft + mslidebarblock.getwidth(); 
            int downbottom = mslidebarblock.getbottom(); 
 
            //边界检测 
            if (downleft < 0) { 
              downleft = 0; 
              downright = mslidebarblock.getmeasuredwidth(); 
            } else if (downright > mslidebarview.getmeasuredwidth()) { 
              downleft = mslidebarview.getmeasuredwidth() - mslidebarblock.getmeasuredwidth(); 
              downright = mslidebarview.getmeasuredwidth(); 
            } 
 
            mslidebarblock.layout(downleft, downtop, downright, downbottom); 
            break; 
          case motionevent.action_move: 
            currentx = (int) event.getx(); 
            int currentpage = currentx * mtotalpage / mslidebarview.getmeasuredwidth(); 
            if (currentpage < 0) { 
              currentpage = 0; 
            } else if (currentpage > mtotalpage) { 
              currentpage = mtotalpage; 
            } 
 
            // 设置滑块的滑动 
            int moveleft = currentx - mslidebarblock.getmeasuredwidth() / 2; 
            int movetop = mslidebarblock.gettop(); 
            int moveright = moveleft + mslidebarblock.getmeasuredwidth(); 
            int movebottom = mslidebarblock.getbottom(); 
 
            //边界处理 
            if (moveleft < 0) { 
              mbound = "left"; 
 
              moveleft = 0; 
              moveright = mslidebarblock.getmeasuredwidth(); 
            } else if (moveright >= mslidebarview.getmeasuredwidth()) { 
              mbound = "right"; 
 
              moveleft = mslidebarview.getmeasuredwidth() - mslidebarblock.getmeasuredwidth(); 
              moveright = mslidebarview.getmeasuredwidth(); 
            } else { 
              mbound = "no"; 
            } 
 
            mslidebarblock.layout(moveleft, movetop, moveright, movebottom); 
            startx = currentx; 
 
            //设置popupwindow的弹出位置 
            if (monslidechangelistener != null) { 
              if (currentpage == mtotalpage) { 
                //防止viewpager越界 
                currentpage = mtotalpage - 1; 
              } 
 
              monslidechangelistener.onslidechange(currentpage); 
 
              if (mpopupwindow != null) { 
                mpopuptext.settext(currentpage + ""); 
 
                //设置popupwindow的滑动 
                if (!mpopupwindow.isshowing()) { 
                  int[] location = new int[2]; 
                  mslidebarview.getlocationinwindow(location); 
                  mpopupwindow.showasdropdown(mslidebarview, currentx, location[1] - mdp40); 
                } else { 
                  if ("no".equals(mbound)) { 
                    int[] location = new int[2] ; 
                    mslidebarview.getlocationinwindow(location); 
                    mpopupwindow.update(currentx, location[1] - mdp40, mpopupwindow.getwidth(), mpopupwindow.getheight(), true); 
                  } 
                } 
              } 
            } 
            break; 
          case motionevent.action_up: 
            currentx = 0; 
            startx = 0; 
            mpopupwindow.dismiss(); 
            break; 
        } 
 
        return true; 
      } 
    }); 
 
    // 初始化popupwindow 
    view contentview = minflater.inflate(r.layout.popup_window, null); 
    mpopuptext = (textview) contentview.findviewbyid(r.id.popup_text); 
    mpopupwindow = new popupwindow(linearlayout.layoutparams.wrap_content, linearlayout.layoutparams.wrap_content); 
    mpopupwindow.setcontentview(contentview); 
    mpopupwindow.setoutsidetouchable(true); 
    mpopupwindow.setbackgrounddrawable(getresources().getdrawable(r.mipmap.popup_window_bg)); 
    mpopupwindow.setanimationstyle(0); 
  } 
 
  int mtotalpage = 0; 
  public void settotalpage(int totalpage) { 
    this.mtotalpage = totalpage; 
  } 
} 

相关的单位转化工具，大家可以拷贝到自己的项目中直接使用。
convertutils.java

package com.jackie.slidebarviewdemo.utils; 
 
import android.content.context; 
 
public class convertutils { 
  public static int dip2px(context context, float dpvalue) { 
    final float scale = context.getresources().getdisplaymetrics().density; 
    return (int) (dpvalue * scale + 0.5f); 
  } 
 
  public static int px2dip(context context, float pxvalue) { 
    final float scale = context.getresources().getdisplaymetrics().density; 
    return (int) (pxvalue / scale + 0.5f); 
  } 
   
  public static int px2sp(context context, float pxvalue) { 
    final float fontscale = context.getresources().getdisplaymetrics().scaleddensity;  
    return (int) (pxvalue / fontscale + 0.5f);  
  }  
   
  public static int sp2px(context context, float spvalue) { 
    final float fontscale = context.getresources().getdisplaymetrics().scaleddensity;  
    return (int) (spvalue * fontscale + 0.5f);  
  } 
} 

自定义组合控件，然后实现相关的手势，思路很清晰，代码也很详细，这里就直接贴代码了。
activity_main.xml

<?xml version="1.0" encoding="utf-8"?> 
<relativelayout 
  xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent"> 
 
  <linearlayout 
    android:layout_width="match_parent" 
    android:layout_height="wrap_content" 
    android:layout_centerinparent="true" 
    android:orientation="vertical"> 
 
    <com.jackie.slidebarviewdemo.widget.slidebarview 
      android:id="@+id/slide_bar" 
      android:layout_width="match_parent" 
      android:layout_height="50dp" 
      android:layout_marginleft="20dp" 
      android:layout_marginright="20dp"/> 
 
    <textview 
      android:id="@+id/text_view" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:layout_gravity="center_horizontal" 
      android:layout_margintop="20dp" 
      android:textcolor="#000" 
      android:textsize="20dp" 
      android:text="当前是第0页"/> 
  </linearlayout> 
</relativelayout> 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?> 
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent"> 
 
  <relativelayout 
    android:id="@+id/slide_bar_view" 
    android:layout_width="match_parent" 
    android:layout_height="50dp"> 
 
    <view 
      android:layout_width="match_parent" 
      android:layout_height="5dp" 
      android:layout_centerinparent="true" 
      android:background="@drawable/shape_slide_bar_bg"/> 
 
    <view 
      android:id="@+id/slide_bar_block" 
      android:layout_width="20dp" 
      android:layout_height="14dp" 
      android:background="#b9b9b9" 
      android:layout_centervertical="true" /> 
  </relativelayout> 
</relativelayout> 

popup_window.xml

<?xml version="1.0" encoding="utf-8"?> 
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android" 
  android:layout_width="match_parent" 
  android:layout_height="match_parent"> 
  <relativelayout 
    android:layout_width="30dp" 
    android:layout_height="30dp"> 
    <textview 
      android:id="@+id/popup_text" 
      android:layout_width="wrap_content" 
      android:layout_height="wrap_content" 
      android:textcolor="#fff" 
      android:textsize="16dp" 
      android:gravity="center" 
      android:layout_centerinparent="true" /> 
  </relativelayout> 
</relativelayout> 

附上相关的资源文件：
shape_slide_bar_bg.xml

<?xml version="1.0" encoding="utf-8"?> 
<shape xmlns:android="http://schemas.android.com/apk/res/android" 
  android:shape="rectangle"> 
  <solid android:color="#dcdcdc" /> 
  <corners android:radius="1dp"/> 
</shape> 

popup_window_bg.9.png

效果如下：

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。