使用 FileProvider 时未找到 Activity 来处理 Intent

No Activity found to handle Intent when using FileProvider

在我的应用程序中,我有一个自定义的自动下载和安装 APK,它的工作方式如下

  // auto register for the complete download
     activity.registerReceiver(onComplete, new IntentFilter(DownloadManager.ACTION_DOWNLOAD_COMPLETE));



 // Download the file through DownloadManager
 String destination = Environment.getExternalStorageDirectory() + "/";
    String fileName = "myfile.apk";
    destination += fileName;
    final Uri uri = Uri.parse("file://" + destination);
    DownloadManager.Request request = new  DownloadManager.Request(Uri.parse(apkUrl));
    request.setDescription("description");
    request.setTitle("title");
    request.setDestinationUri(uri);
    final DownloadManager manager = (DownloadManager) activity.getSystemService(Context.DOWNLOAD_SERVICE);
    final long downloadId = manager.enqueue(request);

onComplete = new BroadcastReceiver() {
      public void onReceive(Context ctxt, Intent intent) {

          Intent install = new Intent(Intent.ACTION_VIEW);
          // BEFORE working doing this
          //install.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
          //install.setDataAndType(uri,
          //    manager.getMimeTypeForDownloadedFile(downloadId));

          // Using file provider it doesnt work
          Uri apkUri = FileProvider.getUriForFile(AutoUpdate.this,
              "com.myapp", file);
                install.setDataAndType(apkUri,manager.getMimeTypeForDownloadedFile(downloadId));
          activity.startActivity(install);
          activity.unregisterReceiver(this);

      }
    };

Android 清单:

<provider
            android:name="android.support.v4.content.FileProvider"
            android:authorities="com.myapp"
            android:exported="false"
            android:grantUriPermissions="true">
            <meta-data
                android:name="android.support.FILE_PROVIDER_PATHS"
                android:resource="@xml/provider_paths"/>
        </provider>

Provider_path(抱歉,由于某些原因所以删除了路径标签)

external-path name="myfolder" path="."/>

当文件下载完成时调用 onComplete 但 activiy 没有启动:

No Activity found to handle Intent { act=android.intent.action.VIEW dat=content://com.myapp/myfolder/myfile.apk typ=application/vnd.android.package-archive flg=0x4000000 }

当使用普通的 file:// 时它确实有效

我在使用文件提供程序时是否遗漏了什么? activity 是否因为找不到文件而没有启动? 我需要额外的许可吗? (目前我有互联网,在外部存储上读写)

软件包安装程序仅支持从 Android 7.0 开始的 content 方案。在此之前——尽管有相反的文档——软件包安装程序只支持 file 方案。

您需要根据您是否 Android 7.0+ 上的 运行 不同地设置 Intent 上的 Uri,例如通过分支Build.VERSION.SDK_INT.

找不到您的提供商,因为

 android:enabled="true"

您的清单中缺少。

但是再看CW的其他回答也不行了

通用软件是对的, 对于那些寻找代码的人:

BroadcastReceiver onComplete = new BroadcastReceiver() {
       public void onReceive(Context ctxt, Intent intent) {

       downloadButton.setEnabled(true);
       downloadButton.setText("Terminado");
       progressbar.setVisibility(View.GONE);

       if (android.os.Build.VERSION.SDK_INT >= Build.VERSION_CODES.N){
            Intent install = new Intent(Intent.ACTION_VIEW);
            install.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

            Uri apkURI = FileProvider.getUriForFile(
                     self,
                     self.getApplicationContext()
                     .getPackageName() + ".provider", file);
            install.setDataAndType(apkURI,
                    manager.getMimeTypeForDownloadedFile(downloadId));
            install.addFlags(Intent.FLAG_GRANT_READ_URI_PERMISSION);
            startActivity(install);
       } else{
            String destination = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS) + "/";
            String fileName = "surveyevent.apk";
            destination += fileName;
            Uri uri = Uri.parse("file://" + destination);

            Intent install = new Intent(Intent.ACTION_VIEW);
            install.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
            install.setDataAndType(uri,
                    manager.getMimeTypeForDownloadedFile(downloadId));
            startActivity(install);
       }
       unregisterReceiver(this);
       finish();
  }
};