Android仿网易严选底部弹出菜单效果

在网易严选的看东西的时候在商品详情页里看到他的底部弹出菜单，本能反应是想用dottomsheetdialog或者popupwindow来实现，可是发现实现不了他那种效果，于是就自己模仿一个像严选这样的底部弹出菜单。

不管是dottomsheetdialog或者popupwindow他们的阴影背景都是全部覆盖的，这就造成除了菜单内容的view之外其他都是阴影的，而严选不是这样的。唠叨到此，首先展示效果图如下：

是不是还可以呢，由于代码量不多却注释详细，所以先贴出代码再一一详说:

bottompopupwindowview类：

 public class bottompopupwindowview extends linearlayout{

  private animatorlistener animatorlistener;
  //底部内容的view
  private framelayout base_view;
  //内容的view
  private framelayout content_view;
  //背景的view
  private relativelayout popup_bg;
  //xml加载的view
  private view bottompopouview;
  //外部加载的内容view
  private view contentview;
  //外部加载的底部内容view
  private view baseview;
  //手势的最小值
  private float minvelocity=0;
  //加载一次的判断值
  private boolean mdrawable=true;

  public void setanimatorlistener(animatorlistener animatorlistener) {
    this.animatorlistener = animatorlistener;
  }

  public void setbaseview(view baseview){
    this.baseview=baseview;
  }

  public void setcontextview(view view){
    this.contentview=view;
  }

  public void setcontentview(int id){
    this.contentview=layoutinflater.from(getcontext()).inflate(id,null);
  }

  public bottompopupwindowview(context context) {
    this(context,null);
  }

  public bottompopupwindowview(context context, @nullable attributeset attrs) {
    this(context,attrs,0);
  }

  public bottompopupwindowview(context context, @nullable attributeset attrs, int defstyleattr) {
    super(context, attrs, defstyleattr);
    //初始化各种数值
    minvelocity=viewconfiguration.get(getcontext()).getscaledtouchslop();
    bottompopouview= layoutinflater.from(getcontext()).inflate(r.layout.layout_bottom_popup,null);
    base_view=(framelayout)bottompopouview.findviewbyid(r.id.bottom_view);
    content_view=(framelayout)bottompopouview.findviewbyid(r.id.content_view);
    popup_bg=(relativelayout)bottompopouview.findviewbyid(r.id.popup_bg);
    //把整个view都加载在linearlayout里以显示出来
    addview(bottompopouview);
    //背景颜色监听
    popup_bg.setonclicklistener(new onclicklistener() {
      @override
      public void onclick(view v) {
        dismisspopupview();
      }
    });

    //屏蔽内容区域点击事件
    content_view.setonclicklistener(new onclicklistener() {
      @override
      public void onclick(view view){}
    });

    //屏蔽底部内容区域点击事件
    base_view.setonclicklistener(new onclicklistener() {
      @override
      public void onclick(view view){}
    });

    //内容区域判断是否向下，手势向下就关闭弹框
    content_view.setontouchlistener(new ontouchlistener() {
      @override
      public boolean ontouch(view view, motionevent motionevent) {
        float y1=0,y2=0;
        if(motionevent.getaction() == motionevent.action_down) {
          y1 = motionevent.gety();
        }
        if(motionevent.getaction() == motionevent.action_up){
          y2 = motionevent.gety();
          if((y2-y1)>minvelocity){
            dismisspopupview();
          }
        }
        return false;
      }
    });

  }

  @override
  protected void ondraw(canvas canvas) {
    super.ondraw(canvas);
    if(mdrawable&&baseview!=null){
      //刚开始加载底部内容区域，只需一次就行，多次报错
      base_view.addview(baseview);
      mdrawable=false;
    }
  }

  public void showpopouview(){
    if(contentview!=null){
      //开始动画数据
      startanimation();
      //开启背景颜色的渐变动画
      popup_bg.setvisibility(view.visible);
      popup_bg.setanimation(animationutils.loadanimation(getcontext(), r.anim.bp_bottom_bg_in));
      //把这个区域全部显示出来
      ((bottompopupwindowview)this).setlayoutparams(new relativelayout.layoutparams(
          relativelayout.layoutparams.match_parent,relativelayout.layoutparams.match_parent));
      //假如内容区域
      content_view.addview(contentview,0);
      content_view.setvisibility(view.visible);
      //开启内容区域动画
      content_view.setanimation(animationutils.loadanimation(getcontext(),r.anim.bp_bottom_view_in));
    }
  }

  public void dismisspopupview(){
    //开始关闭动画数据
    endanimation();
    //开启内容区域动画
    content_view.setvisibility(view.gone);
    animation animation=animationutils.loadanimation(getcontext(),r.anim.bp_bottom_view_out);
    animation.setanimationlistener(new animation.animationlistener() {
      @override
      public void onanimationstart(animation animation) {}
      @override
      public void onanimationrepeat(animation animation) {}
      @override
      public void onanimationend(animation animation) {
        //等内容区域动画结束后，清楚所有view
        content_view.removeallviews();
        //开启背景颜色的渐变动画
        popup_bg.setvisibility(view.gone);
        popup_bg.setanimation(animationutils.loadanimation(getcontext(), r.anim.bp_bottom_bg_out));
        //把整个控件的大小恢复到底部view区域的大小
        relativelayout.layoutparams layoutparams=new relativelayout.layoutparams(
            relativelayout.layoutparams.match_parent,getviewheight((bottompopupwindowview)bottompopupwindowview.this));
        layoutparams.addrule(relativelayout.align_parent_bottom,-1);
        ((bottompopupwindowview)bottompopupwindowview.this).setlayoutparams(layoutparams);
      }
    });
    //开始动画
    content_view.setanimation(animation);
  }

  //获取view的高度
  public int getviewheight(view view){
    int width =view.measurespec.makemeasurespec(0,view.measurespec.unspecified);
    int height =view.measurespec.makemeasurespec(0,view.measurespec.unspecified);
    view.measure(width,height);
    return view.getmeasuredheight();
  }

  //开始动画数据变化
  public void startanimation(){
    valueanimator valueanimator = valueanimator.ofint(0,40);
    valueanimator.setduration(250);
    valueanimator.addupdatelistener(new valueanimator.animatorupdatelistener() {
      @override
      public void onanimationupdate(valueanimator valueanimator) {
        if(animatorlistener!=null){
          animatorlistener.startvalue((int) valueanimator.getanimatedvalue());
        }
      }
    });
    valueanimator.start();
  }

  //结束动画数值变化
  public void endanimation() {
    valueanimator valueanimator = valueanimator.ofint(40,0);
    valueanimator.setduration(250);
    valueanimator.addupdatelistener(new valueanimator.animatorupdatelistener() {
      @override
      public void onanimationupdate(valueanimator valueanimator) {
        if(animatorlistener!=null){
          animatorlistener.endvalue((int) valueanimator.getanimatedvalue());
        }
      }
    });
    valueanimator.start();
  }

}

对应的加载的xml布局是：
layout_bottom_popou.xml如下：

<?xml version="1.0" encoding="utf-8"?>
<relativelayout xmlns:android="http://schemas.android.com/apk/res/android"
  android:orientation="vertical"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:background="#707a7a7a">

  <relativelayout
    android:id="@+id/popup_bg"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="#707a7a7a"
    android:layout_above="@+id/bottom_view"></relativelayout>

  <framelayout
    android:id="@+id/content_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_above="@+id/bottom_view"
    android:orientation="horizontal">
  </framelayout>

  <framelayout
    android:id="@+id/bottom_view"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignparentbottom="true"></framelayout>

</relativelayout>

1.在bottompopupwindowview是继承linearlayout，而layout_bottom_popou.xml是这整个bottompopupwindowview里的骨架，然后在bottompopupwindowview初始化的时候通过addview()来加载整个骨架布局。在ondraw()里只需加载一次baseview就可以了，不然后重复加载导致报错。这样就初始化成功了，刚开始只会加载baseview的界面，就相当于严选最下面的购物车立即购买等界面。

2.当调用showpopouview()时显示菜单的。startanimation()方法只是为了产生动画的数据。

popup_bg.setvisibility(view.visible);
popup_bg.setanimation(animationutils.loadanimation(getcontext(), r.anim.bp_bottom_bg_in));

只是为了开启背景渐变的动画没什么说的。最重要的是显示菜单实现是把bottompopupwindowview的大小扩展到全屏，所以设置((bottompopupwindowview)this).setlayoutparams(new relativelayout.layoutparams(relativelayout.layoutparams.match_parent,relativelayout.layoutparams.match_parent));,然后把弹出菜单的view即contentview装进content_view即可，然后开启弹出动画就实现了。

3.最后是dismisspopupview()方法关闭弹窗。endanimation()方法只是为了产生动画的数据。再启动内容域view即content_view的退出动画，在动画结束后用content_view.removeallviews();
起初菜单内容，再像上面一样开启背景颜色渐变动画，最后只需使bottompopupwindowview恢复原来的baseview的大小及可以了，具体如下:

relativelayout.layoutparams layoutparams=new relativelayout.layoutparams(
     relativelayout.layoutparams.match_parent,getviewheight((bottompopupwindowview)bottompopupwindowview.this));
        layoutparams.addrule(relativelayout.align_parent_bottom,-1);
        ((bottompopupwindowview)bottompopupwindowview.this).setlayoutparams(layoutparams);

这就是核心的代码功能了，代码量不多具体细节看上面的源码。

有人或许会问返回动画的数据有什么用，很简单就是为了实现严选菜单框出来时整个上面详情的缩放。具体看如下demo,首先给出界面xml,如下:

<?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:id="@+id/main_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@color/coloraccent"
    android:orientation="vertical">

    <imageview
      android:id="@+id/banner_img"
      android:layout_width="match_parent"
      android:layout_height="300dp"
      android:scaletype="fitxy"
      android:src="@mipmap/banner"/>

    <view
      android:layout_width="match_parent"
      android:layout_height="0.1dp"
      android:background="@color/colorprimary"></view>

    <relativelayout
      android:id="@+id/guige"
      android:layout_width="match_parent"
      android:layout_height="50dp"
      android:background="#ffffff">

      <textview
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centervertical="true"
        android:layout_marginleft="15dp"
        android:textsize="15dp"
        android:text="规格数量选择"/>

      <imageview
        android:layout_width="20dp"
        android:layout_height="20dp"
        android:layout_alignparentright="true"
        android:layout_centervertical="true"
        android:layout_marginright="15dp"
        android:src="@mipmap/ic_jiantou"/>

    </relativelayout>

    <view
      android:layout_width="match_parent"
      android:layout_height="0.1dp"
      android:background="@color/colorprimary"></view>


  </linearlayout>

  <com.jack.bottompopupwindowview.bottompopupwindowview
    android:id="@+id/bottom_popup"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:background="@android:color/transparent"
    android:layout_alignparentbottom="true">
  </com.jack.bottompopupwindowview.bottompopupwindowview>

</relativelayout>

这就是上面效果图的界面布局，没什么可以说的，再看事例代码如下：

public class mainactivity extends appcompatactivity implements view.onclicklistener, animatorlistener {

  private bottompopupwindowview bottompopupwindowview;
  private view contentview;
  private view bottomview;
  private linearlayout mainview;

  @override
  protected void oncreate(bundle savedinstancestate) {
    super.oncreate(savedinstancestate);
    setcontentview(r.layout.activity_main);
    mainview=(linearlayout)findviewbyid(r.id.main_view);

    bottomview=layoutinflater.from(this).inflate(r.layout.layout_bottom_view,null);
    (bottomview.findviewbyid(r.id.promptly_buy)).setonclicklistener(this);
    (findviewbyid(r.id.guige)).setonclicklistener(this);
    bottompopupwindowview=(bottompopupwindowview)findviewbyid(r.id.bottom_popup);
    bottompopupwindowview.setonclicklistener(this);
    bottompopupwindowview.setbaseview(bottomview);
    contentview=layoutinflater.from(this).inflate(r.layout.layout_content_view,null);
    bottompopupwindowview.setcontextview(contentview);
    (contentview.findviewbyid(r.id.ic_cancel)).setonclicklistener(this);
    bottompopupwindowview.setanimatorlistener(this);
  }

  @override
  public void onclick(view view) {
    switch(view.getid()){
      case r.id.promptly_buy:
      case r.id.ic_cancel:
        bottompopupwindowview.dismisspopupview();
        break;
      case r.id.guige:
        bottompopupwindowview.showpopouview();
        break;
    }
  }

  @override
  public void startvalue(int value) {
    setmargins (mainview,value-10,value,value-10,value);
  }

  @override
  public void endvalue(int value) {
    setmargins (mainview,value,value,value,value);
  }

  public static void setmargins (view v, int l, int t, int r, int b) {
    if (v.getlayoutparams() instanceof viewgroup.marginlayoutparams) {
      viewgroup.marginlayoutparams p = (viewgroup.marginlayoutparams) v.getlayoutparams();
      p.setmargins(l, t, r, b);
      v.requestlayout();
    }
  }
}

其中设置内容菜单的view
bottompopupwindowview.setcontextview(bottomview);
设置没有显示菜单时候显示的view(注:bottomview的高度要和bottompopupwindowview的高度一样，具体看demo)
bottompopupwindowview.setbaseview(bottomview);

而回调的public void startvalue(int value)和public void endvalue(int value)设置动画监听放回的数据，以便根据数据实现动画，严选的弹出和显示商品详情动画很简单就是不断设设置view的间距就可以了。

最后附上demo和源码链接https://github.com/jack921/bottompopupwindowdemo

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。