大家好，我是 aymen 和我的学生，我正在创建一个应用程序，该应用程序显示从 ftp 服务器下载的图像，该图像是网络摄像头的令牌
我想每 2 秒刷新一次图片，但即使有一次我也没有成功，请帮助这是我的代码直到现在
**主要活动**
package com.pfe.ftpstreamer;
import java.io.FileOutputStream;
import com.pfe.ftpstreamer.R;
import com.pfe.ftpstreamer.MyFTPClient;
import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.graphics.BitmapFactory;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
public class MainActivity extends Activity implements OnClickListener {
private static final String TAG = "MainActivity";
private static final String TEMP_FILENAME = "test.txt";
private static final String TEMP_FILENAME1 = "cam.jpg";
private Context cntx = null;
MyFTPClient ftpclient = null;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cntx = this.getBaseContext();
View startButton = findViewById(R.id.button1);
startButton.setOnClickListener(this);
View stopButton = findViewById(R.id.button2);
stopButton.setOnClickListener(this);
View exitButton = findViewById(R.id.button3);
exitButton.setOnClickListener(this);
// Create a temporary file. You can use this to upload
createDummyFile();
ftpclient = new MyFTPClient();
}
public void onClick(View v) {
switch(v.getId()) {
case R.id.button1:
new Thread(new Runnable() {
public void run(){
boolean status = false;
// Replace your UID & PW here
status = ftpclient.ftpConnect("192.168.1.1", "Administrator", "12345", 21);
if (status == true) {
Log.d(TAG, "Connection Success");
status = ftpclient.ftpUpload(TEMP_FILENAME, TEMP_FILENAME, "/", cntx);
//downloading file
ftpclient.ftpDownload(TEMP_FILENAME1,getFilesDir() + "/" +TEMP_FILENAME1);
//removing the file from server
ftpclient.ftpRemoveFile(TEMP_FILENAME1);
//showing the file in the ImageView
new Thread(new Runnable() {
public void run(){
ImageView imgView = (ImageView) findViewById(R.id.imageView1);
imgView.setImageBitmap(BitmapFactory.decodeFile(getFilesDir() + "/" +TEMP_FILENAME1));
}
}).start();
} else {
//Toast.makeText(getApplicationContext(), "Connection failed", 2000).show();
Log.d(TAG, "Connection failed");
}
}
}).start();
break;
case R.id.button2:
new Thread(new Runnable() {
public void run(){
ftpclient.ftpDisconnect();
}
}).start();
break;
case R.id.button3:
this.finish();
break;
}
}
public void createDummyFile() {
try {
FileOutputStream fos;
String file_content = "Hi this is a sample file to upload for android FTP client example";
fos = openFileOutput(TEMP_FILENAME, MODE_PRIVATE);
fos.write(file_content.getBytes());
fos.close();
} catch (Exception e) {
e.printStackTrace();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}}
*myftpclient* *
package com.pfe.ftpstreamer;
import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import org.apache.commons.net.ftp.*;
import android.content.Context;
import android.util.Log;
public class MyFTPClient {
//Now, declare a public FTP client object.
private static final String TAG = "MyFTPClient";
public FTPClient mFTPClient = null;
//Method to connect to FTP server:
public boolean ftpConnect(String host, String username ,
String password, int port)
{
try {
mFTPClient = new FTPClient();
// connecting to the host
mFTPClient.connect(host, port);
// now check the reply code, if positive mean connection success
if (FTPReply.isPositiveCompletion(mFTPClient.getReplyCode())) {
// login using username & password
boolean status = mFTPClient.login(username, password);
/* Set File Transfer Mode
*
* To avoid corruption issue you must specified a correct
* transfer mode, such as ASCII_FILE_TYPE, BINARY_FILE_TYPE,
* EBCDIC_FILE_TYPE .etc. Here, I use BINARY_FILE_TYPE
* for transferring text, image, and compressed files.
*/
mFTPClient.setFileType(FTP.BINARY_FILE_TYPE);
mFTPClient.enterLocalPassiveMode();
return status;
}
} catch(Exception e) {
Log.d(TAG, "Error: could not connect to host " + host );
}
return false;
}
//Method to disconnect from FTP server:
public boolean ftpDisconnect()
{
try {
mFTPClient.logout();
mFTPClient.disconnect();
return true;
} catch (Exception e) {
Log.d(TAG, "Error occurred while disconnecting from ftp server.");
}
return false;
}
//Method to get current working directory:
//Method to change working directory:
//Method to list all files in a directory:
//Method to create new directory:
//Method to delete/remove a directory:
//Method to delete a file:
public boolean ftpRemoveFile(String filePath)
{
try {
boolean status = mFTPClient.deleteFile(filePath);
return status;
} catch (Exception e) {
e.printStackTrace();
}
return false;
}
//Method to rename a file:
//Method to download a file from FTP server:
/**
* mFTPClient: FTP client connection object (see FTP connection example)
* srcFilePath: path to the source file in FTP server
* desFilePath: path to the destination file to be saved in sdcard
*/
public boolean ftpDownload(String srcFilePath, String desFilePath)
{
boolean status = false;
try {
FileOutputStream desFileStream = new FileOutputStream(desFilePath);;
status = mFTPClient.retrieveFile(srcFilePath, desFileStream);
desFileStream.close();
return status;
} catch (Exception e) {
Log.d(TAG, "download failed");
}
return status;
}
//Method to upload a file to FTP server:
/**
* mFTPClient: FTP client connection object (see FTP connection example)
* srcFilePath: source file path in sdcard
* desFileName: file name to be stored in FTP server
* desDirectory: directory path where the file should be upload to
*/
public boolean ftpUpload(String srcFilePath, String desFileName,
String desDirectory, Context context)
{
boolean status = false;
try {
// FileInputStream srcFileStream = new FileInputStream(srcFilePath);
FileInputStream srcFileStream = context.openFileInput(srcFilePath);
// change working directory to the destination directory
//if (ftpChangeDirectory(desDirectory)) {
status = mFTPClient.storeFile(desFileName, srcFileStream);
//}
srcFileStream.close();
return status;
}
catch (Exception e) {
Log.d(TAG, "upload failed: " + e);
}
return status;
}
}