有误差的AsyncTask [英] got error with AsyncTask
本文介绍了有误差的AsyncTask的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!
问题描述
我已经使用AsyncTask的,但我不明白为什么我仍然有错误,当我的设备(OS 4.0)上测试。我的APK建设2.3.3。我想我做到了codeS错了,但我不知道哪里是我的错误。任何人都请帮助我,非常感谢你。
login.java
包com.karismaelearning; 公共类扩展登录活动{
公共Koneksi linkurl;
串SERVER_URL;
私人按钮登录,注册,设置;
私人的EditText用户名,密码;
公共ProgressDialog progressDialog;
@覆盖
公共无效的onCreate(捆绑savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.login); 设置=(按钮)findViewById(R.id.bsetting);
登录=(按钮)findViewById(R.id.login);
注册=(按钮)findViewById(R.id.reg);
用户名=(的EditText)findViewById(R.id.uname);
密码=(EditText上)findViewById(R.id.pass); setting.setOnClickListener(新OnClickListener(){ @覆盖
公共无效的onClick(视图v){
意图intentSet =新意图(Login.this,UrlSetting.class);
startActivity(intentSet);
}
}); register.setOnClickListener(新OnClickListener(){ 公共无效的onClick(视图v){
意图intentReg =新意图(Login.this,Register.class);
startActivity(intentReg);
}
}); login.setOnClickListener(新OnClickListener(){ 公共无效的onClick(视图v){
新LoginTask()执行();
}
}); }
保护字符串tryLogin(字符串mUsername,字符串mPassword){
Log.d(TryLoginCheck,在这里);
HttpURLConnection的连接;
OutputStreamWriter请求= NULL; 网址URL = NULL;
串响应=无效;
字符串TEMP = NULL;
字符串参数=用户名=+ mUsername +&放大器;密码=+ mPassword;
的System.out.println(用户名+ mUsername +\\ n+密码+ mPassword);
Log.d(参数,参数);
尝试{
linkurl =新Koneksi(本);
SERVER_URL = linkurl.getUrl();
SERVER_URL + =/mobile/Login.php;
URL =新的URL(SERVER_URL);
连接=(HttpURLConnection类)url.openConnection();
connection.setDoOutput(真);
connection.setRequestProperty(内容类型,应用程序/ x-WWW的形式urlen codeD);
connection.setRequestMethod(POST); 请求=新OutputStreamWriter(connection.getOutputStream());
request.write(参数);
request.flush();
request.close();
串线=;
InputStreamReader的ISR =新的InputStreamReader(connection.getInputStream());
读者的BufferedReader =新的BufferedReader(ISR);
StringBuilder的SB =新的StringBuilder();
而((行= reader.readLine())!= NULL){
sb.append(行+\\ n);
}
TEMP = sb.toString();
Log.d(温度,温度); 响应= sb.toString();
Log.d(响应,响应);
Log.d(保安局值,sb.toString());
isr.close();
reader.close();
}
赶上(IOException异常五){
Toast.makeText(这一点,e.toString(),Toast.LENGTH_SHORT).show();
} 返回响应;
} 公共类LoginTask扩展的AsyncTask<字符串,字符串,字符串> { 串响应=无效; @覆盖
在preExecute保护无效()
{ }
@覆盖
保护字符串doInBackground(字符串...为arg0)
{
。字符串mUsername = username.getText()的toString();
。字符串mPassword = password.getText()的toString(); 响应= tryLogin(mUsername,mPassword).trim();
返回响应;
}
保护无效onPostExecute(字符串结果){ 如果(结果== NULL)
{
Toast.makeText(Login.this,结果是空值时出错,Toast.LENGTH_SHORT).show();
}
其他{ Log.d(检查,在这里);
Log.d(响应,响应);
如果(response.toLowerCase()。包含(berhasil))
{
字符串NAMA = username.getText()的toString()。
意图newIntent =新意图(Login.this,MainPage.class); 束束=新包(); bundle.putString(非农产品市场准入,NAMA); newIntent.putExtras(包);
startActivityForResult(newIntent,0);
}
其他
{
//可选
// Kalau BISA dibuat不断untuk menghindari萨拉赫penulisan
字符串RoleError =角色SALAH
字符串UserError =USER SALAH createDialog(MAAF,response.equals(RoleError)角色安达bukan学生!?!用户名密码Atau萨拉赫);
}
}
}
}
私人无效createDialog(标题字符串,字符串文本){
AlertDialog广告=新AlertDialog.Builder(本)
.setPositiveButton(OK,NULL)
.setTitle(职称)
.setMessage(文本)
。创建();
ad.show();
}
}
LogCat中
06-10 16:50:00.082:D / TryLoginCheck(4534):在这里
06-10 16:50:00.090:我/的System.out(4534):用户名
06-10 16:50:00.090:我/的System.out(4534):密码
06-10 16:50:00.090:D /参数(4534):用户名=放大器;密码=
06-10 16:50:00.122:W / dalvikvm(4534):主题ID = 11:螺纹未捕获的异常(组= 0x40bd31f8)退出
06-10 16:50:00.129:E / AndroidRuntime(4534):致命异常:AsyncTask的#1
06-10 16:50:00.129:E / AndroidRuntime(4534):了java.lang.RuntimeException:执行doInBackground发生错误()
06-10 16:50:00.129:E / AndroidRuntime(4534):在android.os.AsyncTask $ 3.done(AsyncTask.java:278)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.FutureTask中$ Sync.innerSetException(FutureTask.java:273)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.FutureTask.setException(FutureTask.java:124)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.FutureTask中$ Sync.innerRun(FutureTask.java:307)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.FutureTask.run(FutureTask.java:137)
06-10 16:50:00.129:E / AndroidRuntime(4534):在android.os.AsyncTask $ SerialExecutor $ 1.run(AsyncTask.java:208)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.ThreadPoolExecutor中的$ Worker.run(ThreadPoolExecutor.java:569)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.lang.Thread.run(Thread.java:856)
06-10 16:50:00.129:E / AndroidRuntime(4534):因:显示java.lang.NullPointerException
06-10 16:50:00.129:E / AndroidRuntime(4534):在com.karismaelearning.Login $ LoginTask.doInBackground(Login.java:151)
06-10 16:50:00.129:E / AndroidRuntime(4534):在com.karismaelearning.Login $ LoginTask.doInBackground(Login.java:1)
06-10 16:50:00.129:E / AndroidRuntime(4534):在android.os.AsyncTask $ 2.call(AsyncTask.java:264)
06-10 16:50:00.129:E / AndroidRuntime(4534):在java.util.concurrent.FutureTask中$ Sync.innerRun(FutureTask.java:305)
06-10 16:50:00.129:E / AndroidRuntime(4534):... 5个
06-10 16:50:05.192:D / OpenGLRenderer(4534):刷新缓存(模式0)
06-10 16:50:06.309:D / OpenGLRenderer(4534):冲洗缓存(模式1)
06-10 16:50:07.536:I /流程(4534):发送信号。 PID:4534 SIG:9
解决方案
在tryLogin,在发生异常时你做的:
Toast.makeText(这一点,e.toString(),Toast.LENGTH_SHORT).show();
这是错误的。在 Toast.show()
已对UI线程运行。
在
tryLogin(){ 尝试{ }赶上(IOException异常五){
返回null;
}}
和
保护无效onPostExecute(字符串结果){ 如果(结果== NULL){
Toast.makeText(Login.this,结果是一个空值出现错误),Toast.LENGTH_SHORT).show();
}其他{
结果= result.trim();
//其他的东西
} }@覆盖
保护字符串doInBackground(字符串...为arg0)
{
。字符串mUsername = username.getText()的toString();
。字符串mPassword = password.getText()的toString();
返回tryLogin(mUsername,mPassword);
}
I already use AsyncTask, but I don't understand why I still got error when i tested on my device (OS 4.0) . my apk build in 2.3.3 . I think i made the codes wrong, but i don't know where is my mistake. Anyone please help me, thank you very much
login.java
package com.karismaelearning;
public class Login extends Activity {
public Koneksi linkurl;
String SERVER_URL;
private Button login, register, setting;
private EditText username, password;
public ProgressDialog progressDialog;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.login);
setting = (Button)findViewById(R.id.bsetting);
login = (Button) findViewById(R.id.login);
register = (Button) findViewById(R.id.reg);
username = (EditText) findViewById(R.id.uname);
password = (EditText) findViewById(R.id.pass);
setting.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intentSet = new Intent(Login.this, UrlSetting.class);
startActivity(intentSet);
}
});
register.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Intent intentReg = new Intent(Login.this, Register.class);
startActivity(intentReg);
}
});
login.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
new LoginTask().execute();
}
});
}
protected String tryLogin(String mUsername, String mPassword){
Log.d(" TryLoginCheck ","Here");
HttpURLConnection connection;
OutputStreamWriter request = null;
URL url = null;
String response = null;
String temp=null;
String parameters = "username="+mUsername+"&password="+mPassword;
System.out.println("UserName"+mUsername+"\n"+"password"+mPassword);
Log.d("Parameters",parameters);
try{
linkurl = new Koneksi(this);
SERVER_URL = linkurl.getUrl();
SERVER_URL += "/mobile/Login.php";
url = new URL(SERVER_URL);
connection = (HttpURLConnection) url.openConnection();
connection.setDoOutput(true);
connection.setRequestProperty("Content-Type", "application/x-www-form-urlencoded");
connection.setRequestMethod("POST");
request = new OutputStreamWriter(connection.getOutputStream());
request.write(parameters);
request.flush();
request.close();
String line = "";
InputStreamReader isr = new InputStreamReader(connection.getInputStream());
BufferedReader reader = new BufferedReader(isr);
StringBuilder sb = new StringBuilder();
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
temp=sb.toString();
Log.d("Temp",temp);
response = sb.toString();
Log.d("Response",response);
Log.d("Sb Value",sb.toString());
isr.close();
reader.close();
}
catch(IOException e) {
Toast.makeText(this,e.toString(),Toast.LENGTH_SHORT).show();
}
return response;
}
public class LoginTask extends AsyncTask<String, String, String> {
String response = null;
@Override
protected void onPreExecute()
{
}
@Override
protected String doInBackground(String... arg0)
{
String mUsername = username.getText().toString();
String mPassword = password.getText().toString();
response = tryLogin(mUsername, mPassword).trim();
return response;
}
protected void onPostExecute(String result){
if(result==null)
{
Toast.makeText(Login.this,"result is null- an error occured",Toast.LENGTH_SHORT).show();
}
else{
Log.d("Check","Here");
Log.d("Response",response);
if(response.toLowerCase().contains("berhasil"))
{
String nama = username.getText().toString();
Intent newIntent = new Intent(Login.this, MainPage.class);
Bundle bundle = new Bundle();
bundle.putString("nama", nama);
newIntent.putExtras(bundle);
startActivityForResult(newIntent, 0);
}
else
{
//Optional
//Kalau bisa dibuat constant untuk menghindari salah penulisan
String RoleError = "ROLE SALAH";
String UserError = "USER SALAH";
createDialog("Maaf", response.equals(RoleError) ? "Role Anda bukan Student!" : "Username Atau Password Salah!");
}
}
}
}
private void createDialog(String title, String text) {
AlertDialog ad = new AlertDialog.Builder(this)
.setPositiveButton("Ok", null)
.setTitle(title)
.setMessage(text)
.create();
ad.show();
}
}
LogCat
06-10 16:50:00.082: D/TryLoginCheck(4534): Here
06-10 16:50:00.090: I/System.out(4534): UserName
06-10 16:50:00.090: I/System.out(4534): password
06-10 16:50:00.090: D/Parameters(4534): username=&password=
06-10 16:50:00.122: W/dalvikvm(4534): threadid=11: thread exiting with uncaught exception (group=0x40bd31f8)
06-10 16:50:00.129: E/AndroidRuntime(4534): FATAL EXCEPTION: AsyncTask #1
06-10 16:50:00.129: E/AndroidRuntime(4534): java.lang.RuntimeException: An error occured while executing doInBackground()
06-10 16:50:00.129: E/AndroidRuntime(4534): at android.os.AsyncTask$3.done(AsyncTask.java:278)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.FutureTask$Sync.innerSetException(FutureTask.java:273)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.FutureTask.setException(FutureTask.java:124)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:307)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.FutureTask.run(FutureTask.java:137)
06-10 16:50:00.129: E/AndroidRuntime(4534): at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:208)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1076)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:569)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.lang.Thread.run(Thread.java:856)
06-10 16:50:00.129: E/AndroidRuntime(4534): Caused by: java.lang.NullPointerException
06-10 16:50:00.129: E/AndroidRuntime(4534): at com.karismaelearning.Login$LoginTask.doInBackground(Login.java:151)
06-10 16:50:00.129: E/AndroidRuntime(4534): at com.karismaelearning.Login$LoginTask.doInBackground(Login.java:1)
06-10 16:50:00.129: E/AndroidRuntime(4534): at android.os.AsyncTask$2.call(AsyncTask.java:264)
06-10 16:50:00.129: E/AndroidRuntime(4534): at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:305)
06-10 16:50:00.129: E/AndroidRuntime(4534): ... 5 more
06-10 16:50:05.192: D/OpenGLRenderer(4534): Flushing caches (mode 0)
06-10 16:50:06.309: D/OpenGLRenderer(4534): Flushing caches (mode 1)
06-10 16:50:07.536: I/Process(4534): Sending signal. PID: 4534 SIG: 9
解决方案
in tryLogin, when an Exception occurs you do:
Toast.makeText(this,e.toString(),Toast.LENGTH_SHORT).show();
that's wrong. The Toast.show()
has to run on the UI Thread.
in
tryLogin() {
try {
} catch(IOException e) {
return null;
}
}
and in
protected void onPostExecute(String result){
if (result == null) {
Toast.makeText(Login.this,"result is null- an error occured"),Toast.LENGTH_SHORT).show();
} else {
result = result.trim();
// the other stuff
}
}
@Override
protected String doInBackground(String... arg0)
{
String mUsername = username.getText().toString();
String mPassword = password.getText().toString();
return tryLogin(mUsername, mPassword);
}
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