Android™

Async Task Chain (another example)

See more Async Examples

Demonstrates using a task chain to run a sequence of FTP tasks asynchronously. Android™

// Important: Don't forget to include the call to System.loadLibrary
// as shown at the bottom of this code sample.
package com.test;

import android.app.Activity;
import com.chilkatsoft.*;

import android.widget.TextView;
import android.os.Bundle;

public class SimpleActivity extends Activity {

  private static final String TAG = "Chilkat";

  // Called when the activity is first created.
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    boolean success = false;

    // This example assumes the Chilkat API to have been previously unlocked.
    // See Global Unlock Sample for sample code.

    success = false;

    CkFtp2 ftp = new CkFtp2();

    ftp.put_Hostname("ftp.example.com");
    ftp.put_Username("login");
    ftp.put_Password("password");

    // Connect and login to the FTP server.
    success = ftp.Connect();
    if (success != true) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }

    CkTaskChain taskChain = new CkTaskChain();

    // Create a task to change to the remote directory where the file will be uploaded.
    CkTask task = ftp.ChangeRemoteDirAsync("junk");
    if (ftp.get_LastMethodSuccess() == false) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }

    // Add this task to the task chain.
    success = taskChain.Append(task);

    // Create a task to upload a file.
    String localFilename = "c:/temp/hamlet.xml";
    String remoteFilename = "hamlet.xml";

    task = ftp.PutFileAsync(localFilename,remoteFilename);
    if (ftp.get_LastMethodSuccess() == false) {
        Log.i(TAG, ftp.lastErrorText());
        return;
        }

    // Add this task to the task chain.
    success = taskChain.Append(task);

    // Start the task chain running in a background thread.
    // Each task is run one after the other (on the same background thread) until all tasks have completed.
    // The task chain will stop at the first task that fails.
    taskChain.put_StopOnFailedTask(true);
    success = taskChain.Run();
    if (!success) {
        Log.i(TAG, taskChain.lastErrorText());
        return;
        }

    // The application is now free to do anything else
    // while the FTP commands are being run...

    // For this example, we'll simply sleep and periodically
    // check to see if the taskchain if finished. 
    while (taskChain.get_Finished() != true) {

        // Sleep 100 ms.
        taskChain.SleepMs(100);

        }

    // A finished task chain could be one that was canceled, aborted, or truly finished.  

    // If the task chain "completed", then it ran to completion.  A "completed" task will
    // have a StatusInt equal to 7.   If the task finished, but was not completed, then it must've
    // been aborted or canceled:
    if (taskChain.get_StatusInt() != 7) {
        Log.i(TAG, "Task did not complete.");
        Log.i(TAG, "task chain status: " + taskChain.status());
        return;
        }

    // If we got to this point, the ChangeRemoteDir and PutFile were successful.
    // We can visually verify by examining the LastErrorText that was recorded for each
    // of these method calls..
    int numTasks = taskChain.get_NumTasks();
    int taskIdx = 0;

    while ((taskIdx < numTasks)) {

        task = taskChain.GetTask(taskIdx);

        // Examine the status of this task, and the ResultErrorText
        // (the ResultErrorText is the ftp.LastErrorText captured for FTP method called by the task).
        // Everything should indicate success.
        Log.i(TAG, "task status: " + task.status());
        Log.i(TAG, "task log: " + task.resultErrorText());

        taskIdx = taskIdx + 1;
        }

    success = ftp.Disconnect();

  }

  static {
      System.loadLibrary("chilkat");

      // Note: If the incorrect library name is passed to System.loadLibrary,
      // then you will see the following error message at application startup:
      //"The application <your-application-name> has stopped unexpectedly. Please try again."
  }
}