我正在制作我的第一个 Android 应用程序，但我的代码产生了我无法理解的非常奇怪的行为。我用谷歌三天了，没有解决办法。
如果我在我的 AndroidManifest.xml 中写入除“8”以外的 minSdkVersion，我将无法连接到我的 FTP 服务器。另外，如果我使用 minSdkVersion "8" 和 targetSdkVersion 而不是 "8"。如果我不使用 minSdkVersion 和 targetSdkVersion 一切正常。简而言之：
- 最小 8，目标 8 = ok
- 至少 8，没有目标 = 好的
- 没有最小值，没有目标 = 好的
- 8 分钟，目标 17 = 失败
- 分钟 10，目标 10 = 失败
- 等等...
这是我的 AndroidManifest.xml：
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.package"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8"
android:targetSdkVersion="17" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.package.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name="com.examplepackage.Settings"></activity>
<activity android:name="com.schmidgroup.sgfax.Tools"></activity>
<activity android:name="com.schmidgroup.sgfax.MyFTP"></activity>
<activity android:name="com.schmidgroup.sgfax.Printing"></activity>
<activity android:name="com.schmidgroup.sgfax.Listings"></activity>
<activity android:name="com.schmidgroup.sgfax.Blue"></activity>
</application>
</manifest>
我的 MainActivity.Java：
package com.example.package;
import android.os.Bundle;
import android.app.Activity;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
import android.content.Intent;
import android.view.MenuItem;
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Button for Bluetooth-Connection
Button verbinden = (Button) findViewById(R.id.button1);
verbinden.setText(R.string.select_device);
verbinden.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
Intent start = new Intent(getApplicationContext(), Blue.class);
startActivity(start);
}
} );
}
}
我的 Blue.Java 类做了一些蓝牙工作，然后启动 Listings.Java：
package com.example.package;
import java.io.IOException;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.ArrayAdapter;
import android.widget.AdapterView;
import android.widget.LinearLayout;
import android.widget.ListView;
import android.view.View;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.TextView;
public class Listings extends Activity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.listings);
// Connect zum FTP-Server
MyFTP conn = new MyFTP();
conn.ftpConnect(host, user, pass, 21);
[... some more FTP stuff which don't work in cause of failing Ftp Connection...]
}
}
最后是 MyFTP.Java：
package com.example.package;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.commons.net.ftp.*;
import android.content.Context;
import android.util.Log;
public class MyFTP {
private static void showServerReply(FTPClient FTPClient) {
String[] replies = FTPClient.getReplyStrings();
if (replies != null && replies.length > 0) {
for (String aReply : replies) {
System.out.println("SERVER: " + aReply);
}
}
}
//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);
showServerReply(mFTPClient);
Log.i(TAG, "Successful conntected to " + host);
// 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);
Log.i(TAG, "Succesful logged in to " + host);
/* 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;
}
[...and some more stuff...]
谁能看到我做错了什么？谢谢！