使用DownloadManager时,ListView中的Android ProgressBar

我有一个ListView,其中每个项目代表一个PDF文件.当用户单击某个项目时,该应用程序必须在外部存储上下载该文件.现在下载无法正常运行,但这不是问题.我想要一个ProgressBar,旋转轮样式,在下载文件时出现在列表的每个项目旁边.

我的问题是:我找不到如何使纺车出现.在下载管理器之前,我尝试使用AsyncTask并且旋转轮工作.

这是我的代码:

CategoryActivity.java(ListView的活动)

@Override
public void onItemClick(AdapterView parent, View view,
    int position, long id) {
    // Récupère les valeurs depuis ListItem
    udl = ((TextView) view.findViewById(R.id.udl)).getText().toString();
    // This is the spinning wheel
    loader = ((ProgressBar) view.findViewById(R.id.spinWheel2));

    filepath = dirpath + udl + ".pdf";
    File file = new File(filepath);
    if (file.exists()) {

        // If the file exists, I open it

    }else{ // Else I download it
        // Setting the spinning wheel to VISIBLE
        loader.setVisibility(View.VISIBLE);

        SharedPreferences codeSaveUrl = getSharedPreferences(PREFS_TEXT,Context.MODE_PRIVATE);
        url2 = codeSaveUrl.getString("defaut", ""); // Code Organisation
        // Constructing the uriString
        uri = url10 + url2 + "&file=" + udl ;

        Uri myuri = Uri.parse(uri);
        DownloadManager mgr=(DownloadManager)getSystemService(Context.DOWNLOAD_SERVICE);
        mgr.enqueue(new DownloadManager.Request(myuri)
        .setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI |DownloadManager.Request.NETWORK_MOBILE)
        .setAllowedOverRoaming(false)
        .setTitle(udl + ".pdf")
        .setDescription("Téléchargement en cours")
        .setDestinationInExternalPublicDir("/Protocols/", (udl+".pdf"))
        .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE));                    

        // Hiding the spinning wheel
        loader.setVisibility(View.GONE);

    }
}

请注意,如果我不使纺车轮消失,点击该项目后它将始终可见.使用隐藏它的行,它甚至不会出现.

编辑:
我添加了一个BroadcastReceiver.

将这两行放在onCreate()中:

final DownloadManager mgr=(DownloadManager)getSystemService(Context.DOWNLOAD_SERVICE);
registerReceiver(onComplete, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));

并补充说:

BroadcastReceiver onComplete = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            loader.setVisibility(View.GONE);
        }
    };

    @Override
    public void onDestroy(){
        super.onDestroy();
        unregisterReceiver(onComplete);
    }

编辑2: 好的,这是我做的一些改变:

我将下载的ID保存在变量中:

lastDownload = mgr.enqueue(new DownloadManager.Request(myuri)
                .setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI |DownloadManager.Request.NETWORK_MOBILE)
                .setAllowedOverRoaming(false)
                .setTitle(udl + ".pdf")
                .setDescription("Téléchargement en cours")
                .setDestinationInExternalPublicDir("/Protocols/", (udl+".pdf"))
                .setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE_NOTIFY_COMPLETED));

根据下载的状态,我想做不同的事情:

BroadcastReceiver onComplete = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) {
            Cursor c = mgr.query(new DownloadManager.Query().setFilterById(lastDownload));
            if(c.moveToFirst()){
                int x = c.getInt(c.getColumnIndex(DownloadManager.COLUMN_STATUS));
                switch(x){
                case DownloadManager.STATUS_PAUSED:
                case DownloadManager.STATUS_PENDING:
                case DownloadManager.STATUS_RUNNING:
                    break;
                case DownloadManager.STATUS_SUCCESSFUL:
                    loader.setVisibility(View.GONE);
                    break;
                case DownloadManager.STATUS_FAILED:
                    //TODO: retry download
                    break;
                }
            }

        }
    };

问题是,旋转轮只隐藏在listView中单击的最后一个项目.我尝试使用调试模式,但该程序具有正确的行为(loader.setVisibility(View.GONE)每次下载都会调用该含义).我不知道为什么除了点击的最后一项外,纺车不会隐藏.

编辑:3 我知道为什么除了点击的最后一项外,纺车不会隐藏.

当我点击多个项目时,lastDownload会获取最后一个项目的ID.因此,在广播接收器中,它点击最后一个项目的情况下点击了项目的数量.
我尝试将lastDownload更改为longs数组/表,并将其与referenceId进行比较,我相信它是intent中包含的id.
这是新代码(y = 0,ld是单击的项目数):

BroadcastReceiver onComplete = new BroadcastReceiver() {
        public void onReceive(Context context, Intent intent) { 
            long referenceId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1);
            if(y 

我没有编写将变量放回0的部分,但是现在代码几乎按预期工作.剩下的唯一问题是我制造的纺车消失了最后一个项目的纺车轮点击.而且我知道为什么.因为这一行:   loader = ((ProgressBar) view.findViewById(R.id.spinWheel2));位于onItemClicked方法中.我不认为我可以把它放在其他地方,因为它所在的视图不是活动的视图.

简而言之:我必须找到一种方法来访问我点击的项目/视图的进度条,知道我可以在第一个到达广播接收器之前点击多个项目.



编辑:4好的所以我这样做了:

y,z和ld被设置为0在开始时.

单击某个项目时:

// Loader of the clicked item is made visible
loader[z].setVisibility(View.VISIBLE);

// Construction of the URL
SharedPreferences codeSaveUrl = getSharedPreferences(PREFS_TEXT,Context.MODE_PRIVATE);
url2 = codeSaveUrl.getString("defaut", ""); // Organization code
uri = url10 + url2 + "&file=" + udl ;

// URL parse to URI
Uri myuri = Uri.parse(uri);

// Enqueue file to downloads, with notification. Storage of download id in a table
lastDownload[ld] = mgr.enqueue(new DownloadManager.Request(myuri)
.setAllowedNetworkTypes(DownloadManager.Request.NETWORK_WIFI |DownloadManager.Request.NETWORK_MOBILE)
.setAllowedOverRoaming(false)
.setTitle(udl + ".pdf")
.setDescription("Téléchargement en cours")
.setDestinationInExternalPublicDir("/Protocols/", (udl+".pdf"))
.setNotificationVisibility(DownloadManager.Request.VISIBILITY_VISIBLE));

// Increment variables for next downloads
ld=ld+1;
z=z+1;


广播接收器:

// Broadcast Receiver called when a download is finished
BroadcastReceiver onComplete = new BroadcastReceiver() {
    public void onReceive(Context context, Intent intent) {
        // referenceId is the download's id for which the method is called
        long referenceId = intent.getLongExtra(DownloadManager.EXTRA_DOWNLOAD_ID, -1);
        // If y (=0 at the beginning) is inferior to the number of downloads
        if(y