Java 如何在Android中从PostExecute开始新的意图?
这是我正在编写的代码。当我使用此代码运行我的应用程序时,它会停止运行,不会出现错误 我已经更改了manifest.xml,但它不起作用Java 如何在Android中从PostExecute开始新的意图?,java,android,eclipse,Java,Android,Eclipse,这是我正在编写的代码。当我使用此代码运行我的应用程序时,它会停止运行,不会出现错误 我已经更改了manifest.xml,但它不起作用 public class MainActivity extends Activity { protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity
public class MainActivity extends Activity {
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ok=(Button)findViewById(R.id.Button01);
ok.setOnClickListener(new View.OnClickListener() {
public void onClick(View arg0) {
new jsdetails().execute();
}
});
}
public class jsdetails extends AsyncTask<String,String,String> {
Boolean validUser = false;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Verifying.. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
//int valoreOnPostExecute = 0;
error=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
params.add(new BasicNameValuePair("JS_Email",un.getText().toString()));
params.add(new BasicNameValuePair("JS_Password",pw.getText().toString()));
JSONObject json = jParser.makeHttpRequest(url,"POST",params);
Log.d("All Products: ", json.toString());
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1)
{
validUser = true;
}
} catch (JSONException e) {
e.printStackTrace();
}
return null;
}
protected void onPostExecute(String file_url) {
pDialog.dismiss();
if(validUser)
{
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i);
finish();
}
params.clear();
}
}
}
公共类MainActivity扩展活动{
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
ok=(按钮)findViewById(R.id.Button01);
ok.setOnClickListener(新视图.OnClickListener(){
公共void onClick(视图arg0){
新建jsdetails().execute();
}
});
}
公共类jsdetails扩展了异步任务{
布尔validUser=false;
@凌驾
受保护的void onPreExecute(){
super.onPreExecute();
pDialog=新建进度对话框(MainActivity.this);
pDialog.setMessage(“正在验证..请稍候…”);
pDialog.setUndeterminate(假);
pDialog.setCancelable(假);
pDialog.show();
}
受保护的字符串doInBackground(字符串…args){
//int valoreOnPostExecute=0;
错误=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
add(新的BasicNameValuePair(“JS_Email”,un.getText().toString());
add(新的BasicNameValuePair(“JS_密码”,pw.getText().toString());
JSONObject json=jParser.makeHttpRequest(url,“POST”,参数);
Log.d(“所有产品:,json.toString());
试试{
int success=json.getInt(TAG_success);
如果(成功==1)
{
validUser=true;
}
}捕获(JSONException e){
e、 printStackTrace();
}
返回null;
}
受保护的void onPostExecute(字符串文件\u url){
pDialog.disclose();
if(validUser)
{
Intent i=新的Intent(getApplicationContext(),MainActivity.class);
星触觉(i);
完成();
}
参数clear();
}
}
}
试试这个。。移除finish()代码>
试试这个。。移除finish()代码>
必须对UIThread执行查看操作。后台线程上的异步doInBackground方法。您无法在后台线程中获取editText的文本。您必须在UIThread上执行查看操作。后台线程上的异步doInBackground方法。您无法在后台线程中获取editText的文本。您在doinbackground()方法中返回null,而在onPostExecute中返回valid user
protected void onPostExecute(String validUser) {
pDialog.dismiss();
if(validUser)
{
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i);
finish();
}
params.clear();
}
}
您将在doinbackground()方法中返回null,而不是在onPostExecute中返回valid user
protected void onPostExecute(String validUser) {
pDialog.dismiss();
if(validUser)
{
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i);
finish();
}
params.clear();
}
}
像这样做
public class jsdetails extends AsyncTask<String,String,Boolean> {
Boolean validUser = false;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Verifying.. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected Boolean doInBackground(String... args) {
//int valoreOnPostExecute = 0;
error=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
params.add(new BasicNameValuePair("JS_Email",un.getText().toString()));
params.add(new BasicNameValuePair("JS_Password",pw.getText().toString()));
JSONObject json = jParser.makeHttpRequest(url,"POST",params);
Log.d("All Products: ", json.toString());
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1)
{
validUser = true;
}
} catch (JSONException e) {
e.printStackTrace();
}
return validUser;
}
protected void onPostExecute(Boolean validUser) {
pDialog.dismiss();
if(validUser)
{
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i);
finish();
}
params.clear();
}
}
}***
public类jsdetails扩展异步任务{
布尔validUser=false;
@凌驾
受保护的void onPreExecute(){
super.onPreExecute();
pDialog=新建进度对话框(MainActivity.this);
pDialog.setMessage(“正在验证..请稍候…”);
pDialog.setUndeterminate(假);
pDialog.setCancelable(假);
pDialog.show();
}
受保护的布尔doInBackground(字符串…args){
//int valoreOnPostExecute=0;
错误=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
add(新的BasicNameValuePair(“JS_Email”,un.getText().toString());
add(新的BasicNameValuePair(“JS_密码”,pw.getText().toString());
JSONObject json=jParser.makeHttpRequest(url,“POST”,参数);
Log.d(“所有产品:,json.toString());
试试{
int success=json.getInt(TAG_success);
如果(成功==1)
{
validUser=true;
}
}捕获(JSONException e){
e、 printStackTrace();
}
返回validUser;
}
受保护的void onPostExecute(布尔validUser){
pDialog.disclose();
if(validUser)
{
Intent i=新的Intent(getApplicationContext(),MainActivity.class);
星触觉(i);
完成();
}
参数clear();
}
}
}***
像这样做
public class jsdetails extends AsyncTask<String,String,Boolean> {
Boolean validUser = false;
@Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(MainActivity.this);
pDialog.setMessage("Verifying.. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected Boolean doInBackground(String... args) {
//int valoreOnPostExecute = 0;
error=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
params.add(new BasicNameValuePair("JS_Email",un.getText().toString()));
params.add(new BasicNameValuePair("JS_Password",pw.getText().toString()));
JSONObject json = jParser.makeHttpRequest(url,"POST",params);
Log.d("All Products: ", json.toString());
try {
int success = json.getInt(TAG_SUCCESS);
if (success == 1)
{
validUser = true;
}
} catch (JSONException e) {
e.printStackTrace();
}
return validUser;
}
protected void onPostExecute(Boolean validUser) {
pDialog.dismiss();
if(validUser)
{
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i);
finish();
}
params.clear();
}
}
}***
public类jsdetails扩展异步任务{
布尔validUser=false;
@凌驾
受保护的void onPreExecute(){
super.onPreExecute();
pDialog=新建进度对话框(MainActivity.this);
pDialog.setMessage(“正在验证..请稍候…”);
pDialog.setUndeterminate(假);
pDialog.setCancelable(假);
pDialog.show();
}
受保护的布尔doInBackground(字符串…args){
//int valoreOnPostExecute=0;
错误=(TextView)findViewById(R.id.TextView01);
un=(EditText)findViewById(R.id.EditText01);
pw=(EditText)findViewById(R.id.EditText02);
add(新的BasicNameValuePair(“JS_Email”,un.getText().toString());
add(新的BasicNameValuePair(“JS_密码”,pw.getText().toString());
JSONObject json=jParser.makeHttpRequest(url,“POST”,参数);
Log.d(“所有产品:,json.toString());
试试{
int success=json.getInt(TAG_success);
如果(成功==1)
{
validUser=true;
}
}抓住(