小编fus*_*n27的帖子

我正在构建一个带有PhoneGap的音频媒体记录器/播放器.这一切都很美妙,但我已经发现了一些我似乎无法解决的问题.

my_media.play();确实在我的Eclipse或XCode控制台中播放没有错误的媒体,这就是显示-1的警报令人费解的原因.我希望my_media.getDuration();返回我正在尝试播放的文件的持续时间.

我的try/catch块没有抛出错误,我对这个感到很困惑. 这是关于Media.getDuration()的PhoneGap文档.

function playAudio() {

    $('#btnStopRecording').removeClass('ui-disabled');
    $('#btnPlayMessage, #btnStartStopRecording, #btnDeleteMessage, #btnAcceptUpload').addClass('ui-disabled');

    my_media = new Media(fullRecordPath,

        // success callback
        function () {
            $('#btnPlayMessage, #btnStartStopRecording, #btnDeleteMessage, #btnAcceptUpload').removeClass('ui-disabled');
            $('#btnStopRecording').addClass('ui-disabled');
        },

        // error callback
        function (err) {
            console.log("attempting to play fullRecordPath = "+fullRecordPath);
            console.log("playAudio():Audio Error: " + err.code);
        }
    );

    var thisDuration;

    try{
        thisDuration = my_media.getDuration();
    } catch (err) {
        console.log("attempting to get duration error code "+err.code);
        console.log("attempting to get duration error message "+err.message);
    }

    alert("we're about play a …

我有一个实体试图调用一个与DAO交谈的门面(我称之为步骤).当我观察/设置断点时,只有这种情况下的实体管理器为空(违规行>> http://goo.gl/rqyRg).Java仍然有点绿,希望从你们中间的人中收集一些能够在正确的调试方向上滚动的东西.现在,我怀疑问题是我自己的头骨厚度.

这是违规的门面.<< StepsFacade.java >>

package com.mdjdreview.session;

import com.mdjdreview.dao.Steps;
import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.NoResultException;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;


@Stateless
public class StepsFacade extends AbstractFacade<Steps> {
    @PersistenceContext(unitName = "MdJdReviewPU2")
    private EntityManager em;

    @Override
    protected EntityManager getEntityManager() {
        return em;
    }

    public StepsFacade() {
        super(Steps.class);
    }

    public Object findAllRange(int low, int high) {
        try {
            Query q = this.em.createNamedQuery("Steps.findAllRange");
            q.setMaxResults(high);
            q.setFirstResult(low);
            return q.getResultList();
        }
        catch(NoResultException ex) {
            return null;
        }
    }

    public Object findByPatternRange(String title, int low, int high) { …