我必须做一个应用程序，它应该适用于所有 2.2+ 版本。我已经在安卓设备和模拟器中进行了测试。但是这个应用程序可以在几个版本中运行，但不能在更高版本中运行，如果我启动我的应用程序，我会收到空值错误。我不知道为什么会这样。根据我的假设“如果我们为应该在所有其他更高版本中工作的较低版本开发应用程序”，但那是行不通的。请帮我。
这是我在 2.2、2.3 和几个更高版本中工作的代码。但不适用于 3.2 及更高版本。我得到空值
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.main_geotracker);
textbox1 = (TextView) findViewById(R.id.textinname1);
textbox2 = (TextView) findViewById(R.id.textinname2);
ConnectivityManager cm = (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo ni = cm.getActiveNetworkInfo();
if (ni != null && ni.isConnected())
{
msg = "Please login to continue";
login();
}
else
{
msg = "Sorry , network connection is not available.";
message();
}
}
//Login------------------------------------------------------------------------------------
public void login()
{
final EditText uname = new EditText(this);
final EditText upassword = new EditText(this);
DialogInterface.OnClickListener dialogClickListener = new DialogInterface.OnClickListener()
{
// DialogInterface called while setting the AlertDialog Buttons
public void onClick(DialogInterface dialog, int which)
{
//Here you can perform functions of Alert Dialog Buttons as shown
switch(which)
{
case DialogInterface.BUTTON_POSITIVE:
if(!uname.getText().toString().equals("") && !upassword.getText().toString().equals(""))
{
session_name = uname.getText().toString();
session_pwd = upassword.getText().toString();
try
{
uid = httppost(uname.getText().toString(), upassword.getText().toString(), "login.php"); //Here Iam getting null value.
Log.i("TAG", ""+uid);
}
catch(JSONException e)
{
// TODO Auto-generated catch block
e.printStackTrace();
}
if(uid == null || uid.length() == 6)
{
msg = "Either user name or password or both incorrect.";
login();
}
else
{
Toast.makeText(getApplicationContext(), "Hello " + uname.getText().toString() + ", You have successfully logged in..:)", Toast.LENGTH_LONG).show();
IDList()
}
}
else
{
Toast.makeText(getApplicationContext(), "Sorry, Either user name or password or both incorrect..:(", Toast.LENGTH_LONG).show();
msg = "Both user name and password are mandatory fields.";
login();
}
break;
case DialogInterface.BUTTON_NEGATIVE:
exit();
break;
}
}
};
AlertDialog.Builder builder = new AlertDialog.Builder(this);
LinearLayout orientation = new LinearLayout(this);
orientation.setOrientation(1); //1 is for vertical orientation
uname.setHint("Enter name");
upassword.setHint("Enter password");
upassword.setInputType(InputType.TYPE_CLASS_TEXT | InputType.TYPE_TEXT_VARIATION_PASSWORD);
orientation.addView(uname);
orientation.addView(upassword);
builder.setView(orientation);
builder.setMessage(msg);
builder.setTitle("Login")
.setIcon(R.drawable.ic_launcher)
.setPositiveButton("Submit", dialogClickListener)
.setNegativeButton("Exit App", dialogClickListener).show();
}
public String httppost(String param1, String param2, String file) throws JSONException
{
try
{
String data = URLEncoder.encode("param1", "UTF-8") + "=" + URLEncoder.encode(param1, "UTF-8");
data += "&" + URLEncoder.encode("param2", "UTF-8") + "=" + URLEncoder.encode(param2, "UTF-8");
// Send data
URL url = new URL("http://192.168.1.12/GeoTracker/android/"+file);
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(data);
wr.flush();
// Get the response
BufferedReader rd = new BufferedReader(new InputStreamReader(conn.getInputStream()));
the_string_response = rd.readLine();
wr.close();
rd.close();
}
catch (Exception e)
{
}
textbox1.setText("");
textbox2.setText("");
return the_string_response;
}
这是我的原木猫，
`05-21 19:12:50.610: D/dalvikvm(4100): Late-enabling CheckJNI
05-21 19:12:50.850: E/PhonePolicy(4100): Could not preload class for phone policy: com.android.internal.policy.impl.PhoneWindow$ContextMenuCallback
05-21 19:12:50.970: D/TextLayoutCache(4100): Using debug level: 0 - Debug Enabled: 0
05-21 19:12:51.160: I/dalvikvm(4100): threadid=1: recursive native library load attempt (/system/lib/libwebcore.so)
05-21 19:12:51.160: D/dalvikvm(4100): No JNI_OnLoad found in /system/lib/libchromium_net.so 0x0, skipping init
05-21 19:12:51.220: D/dalvikvm(4100): GC_CONCURRENT freed 134K, 4% free 5078K/5255K, paused 1ms+1ms
05-21 19:12:51.750: D/libEGL(4100): loaded /system/lib/egl/libEGL_mali.so
05-21 19:12:51.760: D/libEGL(4100): loaded /system/lib/egl/libGLESv1_CM_mali.so
05-21 19:12:51.770: D/libEGL(4100): loaded /system/lib/egl/libGLESv2_mali.so
05-21 19:12:51.820: D/OpenGLRenderer(4100): Enabling debug mode 0
05-21 19:12:59.690: D/dalvikvm(4100): GC_CONCURRENT freed 159K, 5% free 5329K/5575K,
paused 2ms+4ms`
05-21 19:13:11.500: I/TAG(4100): null
请帮助我，提前谢谢...