library/src/main/java/com/liulishuo/filedownloader/FileDownloader.java
public void bindService(final Runnable runnable) {
        if (isServiceConnected()) {
            runnable.run();
        } else {
            FileDownloadServiceProxy.getImpl().
                    bindStartByContext(FileDownloadHelper.getAppContext(), runnable);
        }
    }
public void bindService(final Runnable runnable) {
        if (isServiceConnected()) {
            runnable.run();
        } else {
            FileDownloadServiceProxy.getImpl().
                    bindStartByContext(FileDownloadHelper.getAppContext(), runnable);
        }
    }
Start and bind the FileDownloader service and run {@code runnable} as soon as the binding is
successful.
<p>
<strong>Tips:</strong> The FileDownloader service will start and bind automatically when any
task is request to start.

@param runnable the command will be executed as soon as the FileDownloader Service is
successfully bound.
@see #isServiceConnected()
@see #bindService()
@see #addServiceConnectListener(FileDownloadConnectListener)