关于Android实现简单的微信朋友圈分享功能

<activity 
      android:name=".wxapi.wxentryactivity" 
      android:exported="true">//产生回调 
    </activity> 

private final string app_id= "wx108514397eea5f77"; 
  private iwxapi api; 
  @override 
  protected void oncreate(bundle savedinstancestate) { 
    super.oncreate(savedinstancestate); 
    setcontentview(r.layout.activity_wxentry); 
    api = wxapifactory.createwxapi(this, app_id, false); 
    api.registerapp(app_id); 
    api.handleintent(getintent(), this); 
  } 
  @override 
  public void onreq(basereq basereq) { 
  } 
  @override 
  public void onresp(baseresp baseresp) { 
    switch (baseresp.errcode) { 
      case baseresp.errcode.err_ok: 
        toast.maketext(this, "分享成功", toast.length_long).show(); 
        break; 
      case baseresp.errcode.err_user_cancel: 
        toast.maketext(this, "分享取消", toast.length_long).show(); 
        break; 
      case baseresp.errcode.err_auth_denied: 
        toast.maketext(this, "被拒绝", toast.length_long).show(); 
        break; 
      default: 
        toast.maketext(this, "未知错误", toast.length_long).show(); 
        break; 
    } 
    finish(); 
  }

private void weichat(int flag) { 
    if (!api.iswxappinstalled()) { 
      return; 
    } 
    //创建一个wxwebpageobject对象，用于封装要发送的url 
    wxwebpageobject webpage = new wxwebpageobject(); 
    webpage.webpageurl = "http://www.baidu.com/"; 
    //创建一个wxmediamessage对象 
    wxmediamessage msg = new wxmediamessage(webpage); 
    msg.title = "测试"; 
    msg.description = "ceshi "; 
    sendmessagetowx.req req = new sendmessagetowx.req(); 
    req.transaction = string.valueof(system.currenttimemillis());//transaction字段用于唯一标识一个请求，这个必须有，否则会出错 
    req.message = msg; 
    //表示发送给朋友圈 wxscenetimeline 表示发送给朋友 wxscenesession 
    req.scene = flag == 0 ? sendmessagetowx.req.wxscenesession : sendmessagetowx.req.wxscenetimeline; 
    api.sendreq(req); 
  }