Develop Reference

ProgressBar not showing up

Edit: I realized that the code posted below works flawlessly in Nexus 6 (shamu) and Galaxy Tab A, both with android 7.0! And it does not show on Moto G5 Plus (android 7.0).
It's a simple question. My ProgressBar won't show up. At frist I was trying directly at my LoginActivity, but I wasn't having success. Things that i tried:
Put ProgressBar directly inside the layout
Put ProgressBar inside a layout
Set ProgressBar propriety indeterminate to true
Set the visibility of progressbar and parent layout to VISIBLE
Create a separated .xml file and call a Dialog (in this case, if I put a textview inside the text will appear but the progressbar won't)
Change the proprieties layout_width and layout_height
A combination of all the steps above
Last I tryed to create this simple blank activity showing only the progress bar...
activity_test.xml:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="context_name_here">
<LinearLayout
android:layout_width="368dp"
android:layout_height="495dp"
android:layout_marginBottom="8dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:orientation="vertical"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent">
<ProgressBar
android:id="#+id/progressBar2"
style="?android:attr/progressBarStyle"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:indeterminate="true"
android:visibility="visible" />
</LinearLayout>
</android.support.constraint.ConstraintLayout>
test.java:
package package_name_here;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
public class test extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
}
}
What's the problem? I suspect that is something about the resources... the image of the default progressbar or version of android...
any ideas?
Thanks

I figured out what was the problem.
The Animator duration scale have to be ON at Developer options from device:
Developer options -> Developer duration scale -> 1x (ON)

Try with hard-coded dimension for the width and height for ProgressBar, also check your Colors that might be the same as activity default, also check by removing the style attribute once, or try with a different style for ProgressBar.

import android.os.Handler;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.ProgressBar;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private ProgressBar progressBar;
private int progressStatus = 0;
private TextView textView;
private Handler handler = new Handler();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
progressBar = (ProgressBar) findViewById(R.id.progressBar);
textView = (TextView) findViewById(R.id.textView);
// Start long running operation in a background thread
new Thread(new Runnable() {
public void run() {
while (progressStatus < 100) {
progressStatus += 1;
// Update the progress bar and display the
//current value in the text view
handler.post(new Runnable() {
public void run() {
progressBar.setProgress(progressStatus);
textView.setText(progressStatus+"/"+progressBar.getMax());
}
});
try {
// Sleep for 200 milliseconds.
Thread.sleep(200);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
}
}).start();
}
}
Define XML:
<ProgressBar
android:id="#+id/progressBar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginLeft="23dp"
android:layout_marginTop="20dp"
android:indeterminate="false"
android:max="100"
android:minHeight="50dp"
android:minWidth="200dp"
android:progress="1" />
<ProgressBar
android:id="#+id/progressBar_cyclic"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:minHeight="50dp"
android:minWidth="50dp"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />

First you need to declare the progress dialog
private ProgressBar progressBar;
then in your onCreate
progressBar = (ProgressBar) findViewById(R.id.progressBar);
progressBar= new ProgressBar(test.this);
progressBar.show();
to dismiss the dialog or cancel it you can use
progressBar.cancel(); or progressBar.dismiss();

How to add a Progress Bar in a PreferenceFragment in Android?

How can I add a progress bar in a PreferenceFragment? I have some async task running that will display some values in my preference upon completion. So while it is doing the background process, I plan to show only a progress bar in the center. After the task is complete, then I plan to show all my preferences.
Here's what I have so far.
PreferenceFragment
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.pref_account);
}
#Override
public void onActivityCreated(#Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
new AsyncTask<Void,Void,Void>() {
String firstName, lastName, email;
#Override
protected void doInBackground() {
// Doing something here to fetch values
}
#Override
protected void onPostExecute() {
findPreference("first_name").setSummary(firstName);
findPreference("last_name").setSummary(lastName);
findPreference("email").setSummary(email);
}
}
}
pref_account.xml
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<Preference android:key="first_name"
android:title="#string/prompt_first_name"
android:summary="" />
<Preference android:key="last_name"
android:title="#string/prompt_last_name"
android:summary="" />
<Preference android:key="email"
android:title="#string/prompt_email"
android:summary=""
android:inputType="textEmailAddress" />
<Preference android:key="sign_out"
android:title="#string/action_sign_out" />
</PreferenceScreen>
My question is, since this is a PreferenceFragment and I'm not overriding the method onCreateView, where and how should I add the progress bar?

Here's what I did:
Create a custom Preference class:
public class LoadingPreference extends Preference {
public LoadingPreference(Context context){
super(context);
setLayoutResource(R.layout.preference_loading_placeholder);
}
}
Create a custom Layout (preference_loading_placeholder) while preserving the Preference layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:minHeight="?android:attr/listPreferredItemHeight"
android:gravity="center_vertical"
android:paddingEnd="?android:attr/scrollbarSize"
android:background="?android:attr/selectableItemBackground" >
<ImageView
android:id="#+android:id/icon"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_gravity="center"/>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="15dip"
android:layout_marginEnd="6dip"
android:layout_marginTop="6dip"
android:layout_marginBottom="6dip"
android:layout_weight="1">
<!-- (start) I added this part. -->
<ProgressBar
android:id="#+id/progressBar"
android:layout_centerInParent="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:indeterminateTintMode="src_atop"
android:indeterminateTint="#color/colorAccent"
android:layout_gravity="center" />
<TextView
android:id="#+id/progressTitle"
android:text="#string/loading"
android:textSize="24sp"
android:textColor="#color/colorAccent"
android:layout_centerVertical="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginRight="16dp"
android:layout_toLeftOf="#+id/progressBar" />
<!-- (end) I added this part. -->
<TextView android:id="#+android:id/title"
android:layout_width="0dp"
android:layout_height="0dp"
android:singleLine="true"
android:textAppearance="?android:attr/textAppearanceLarge"
android:ellipsize="marquee"
android:fadingEdge="horizontal" />
<TextView android:id="#+id/summary"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_below="#android:id/title"
android:layout_alignStart="#android:id/title"
android:textAppearance="?android:attr/textAppearanceSmall"
android:textColor="?android:attr/textColorSecondary"
android:maxLines="4" />
</RelativeLayout>
<!-- Preference should place its actual preference widget here. -->
<LinearLayout android:id="#+id/widget_frame"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center_vertical"
android:orientation="vertical"/>
</LinearLayout>
Used a PreferenceCategory to hold my loading preference:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android">
<SwitchPreference
android:key="#string/pref_key_wifi_enabled"
android:title="#string/pref_title_wifi_enabled"
android:summary="#string/pref_summary_wifi_enabled" />
<Preference
android:key="#string/pref_key_wifi_refresh"
android:title="#string/pref_title_wifi_refresh"
android:summary="#string/pref_summary_wifi_refresh"
android:dependency="#string/pref_key_wifi_enabled"/>
<PreferenceCategory
android:key="#string/pref_key_wifi_section"
android:title="#string/pref_title_wifi_section"
android:summary="#string/pref_summary_wifi_section"
android:dependency="#string/pref_key_wifi_enabled"/>
</PreferenceScreen>
Put the loading preference where needed
((PreferenceCategory)findPreference(WIFI_OPTIONS_SECTION_KEY)).addPreference(new LoadingPreference(getActivity()));
Remove the loading preference after loading is complete:
((PreferenceCategory)findPreference(WIFI_OPTIONS_SECTION_KEY)).removeAll();
Add other preferences after loading is complete:
Preference p = new Preference(getActivity());
p.setTitle("...");
p.setSumary("...")
((PreferenceCategory)findPreference(WIFI_OPTIONS_SECTION_KEY)).addPreferece(p);

I had a similar use case and I used a custom layout for the preference.
In the preference fragment file I had (non relevant attributes are omitted)
<!-- res/xml/somePref.xml -->
<PreferenceScreen>
<PreferenceCategory>
...
<Preference android:widgetLayout="#layout/customLayout" />
...
</PreferenceCategory>
</PreferenceScreen>
Then in the custom layout I placed the progress bar by itself
<!-- res/layout/customLayout.xml -->
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/progress"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone">
<ProgressBar
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true"
android:indeterminateOnly="true" />
</RelativeLayout>
Before starting the async task I call
findViewById(R.id.progress).setVisibility(View.VISIBLE)
and when the task is done I set the visibility back to gone. This will allow you to set each preference independently without having to wait for each one to complete. Hope this helps.

I ended up using the following approach.
In my fragment_account.xml layout file.
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<ProgressBar
android:id="#+id/progress_bar"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerInParent="true" />
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:visibility="gone" />
</RelativeLayout>
Then on my class:
public class AccountFragment extends PreferenceFragment {
private ListView mListView;
private ProgressBar mProgressBar;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_account, container, false);
mListView = (ListView) view.findViewById(android.R.id.list);
mProgressBar = (ProgressBar) view.findViewById(R.id.progress_bar);
showProgress();
return view;
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
addPreferencesFromResource(R.xml.pref_account);
hideProgress();
}
private void showProgress() {
mListView.setVisibility(View.GONE);
mProgressBar.setVisibility(View.VISIBLE);
}
private void hideProgress() {
mListView.setVisibility(View.VISIBLE);
mProgressBar.setVisibility(View.GONE);
}
}
}

You could try to apply the following solution:
Use fragments in your preference activity.
When you need to display preferences - display preference fragment.
When you need to display progress - display progress fragment.
Here is a code excerpt:
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
showPreferences();
// or call showProgress, launch your task and call showPreferences upon completion
}
private void showPreferences() {
runOnUiThread(new Runnable() {
#Override
public void run() {
getFragmentManager()
.beginTransaction()
.replace(android.R.id.content, new YourPreferenceFragment())
.commit();
}
});
}
private void showProgress() {
runOnUiThread(new Runnable() {
#Override
public void run() {
getFragmentManager()
.beginTransaction()
.replace(android.R.id.content, new YourProgressFragment())
.commit();
}
});
}

Use this approach. Create one Dialog with a custom layout which a progressBar in it and just call show() and dismiss().
#Synchronized
fun showLoader(activity: Activity) {
val activityWeakReference = WeakReference(activity)
if (activityWeakReference.get() != null) {
hideLoader()
dialog = Dialog(activityWeakReference.get()!!, android.R.style.Theme_Translucent)
dialog?.window?.requestFeature(Window.FEATURE_NO_TITLE)
dialog?.setContentView(R.layout.progress_indicator)
dialog?.setCancelable(false)
dialog?.show()
}
}
#Synchronized
fun hideLoader() {
dialog?.dismiss()
dialog = null
}

Use the following concept in AsyncTasks default Methods
private class MyAsynTask extends AsyncTask<String, String, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
showDialog();// show your progressbar
}
#Override
protected String doInBackground(String... urls) {
//your code
}
protected void onProgressUpdate(String... progress) {
progressDialog.setProgress(Integer.parseInt(progress[0]));
// here you get the value of progress
}
#Override
protected void onPostExecute(String result) {
dismissDialog(); //dismiss progressbar
}
}

Android ProgressBar styled like progress view in SwipeRefreshLayout

I use android.support.v4.widget.SwipeRefreshLayout in my Android app. It wraps a ListView. The content of the list view is downloaded from a server.
A progress view is shown when user swipes down in order to reload data from server. The progress view looks like a piece of circle that grows and shrinks during the animation. It seems that the style of this progress view cannot be customized much. However, I am fine with its built-in style.
I also show the same progress animation during initial data loading. This can be achieved by calling mySwipeRefreshLayout.setRefreshing(true). That's perfectly OK too.
However, I would like to show the same progress indication through the whole app. Consider e.g. another activity that looks like a form with submit button. There is neither a ListView nor a SwipeRefreshLayout in this form activity. Some progress indication should be displayed while the submitted data are transferred to the server. I want to show a progress bar with the same animation like in SwipeRefreshLayout.
Is there a simple and clean way to have the same progress indicator for both a SwipeRefreshLayout and a form activity that does not contain any list view and refresh layout and does not support any swipe gesture?
Thanks.

However, I would like to show the same progress indication through the
whole app. Consider e.g. another activity that looks like a form with
submit button. There is neither a ListView nor a SwipeRefreshLayout in
this form activity. Some progress indication should be displayed while
the submitted data are transferred to the server. I want to show a
progress bar with the same animation like in SwipeRefreshLayout.
yes you can use SwipeRefreshLayout to show like ProgressDialog when button click. check below.
i have added SwipeRefreshLayout inside my layout file still there is not ListView or ScrollView. just like below
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="niu.com.djandroid.jdroid.androidstack.MainActivity"
tools:showIn="#layout/activity_main">
<android.support.v4.widget.SwipeRefreshLayout
android:id="#+id/activity_main_swipe_refresh_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hello World!" />
<SeekBar
android:id="#+id/seekBar"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="54dp" />
<Button
android:id="#+id/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Button" />
</LinearLayout>
</android.support.v4.widget.SwipeRefreshLayout>
</LinearLayout>
now in my activity i used AsyncTask to show SwipeRefreshLayout. also use mSwipeRefreshLayout.setOnRefreshListener(null) to stop swipe gesture.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mSwipeRefreshLayout = (SwipeRefreshLayout) findViewById(R.id.activity_main_swipe_refresh_layout);
mSwipeRefreshLayout.setOnRefreshListener(null);
((Button) findViewById(R.id.button)).setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// mSwipeRefreshLayout.setRefreshing(true);
// call AsyncTask
new LongOperation().execute("");
}
});
}
private class LongOperation extends AsyncTask<String, Void, String> {
#Override
protected String doInBackground(String... params) {
for (int i = 0; i < 5; i++) {
try {
Thread.sleep(1000);
} catch (InterruptedException e) {
Thread.interrupted();
}
}
return "Executed";
}
#Override
protected void onPostExecute(String result) {
// stop mSwipeRefreshLayout
mSwipeRefreshLayout.setRefreshing(false);
}
#Override
protected void onPreExecute() {
// start mSwipeRefreshLayout
mSwipeRefreshLayout.setRefreshing(true);
}
#Override
protected void onProgressUpdate(Void... values) {
}
}
EDITED:15/02/20
After 4 year, Here is great explanation on android developer site

mSwipeRefreshLayout.setOnRefreshListener(null)
didn't work for me, so I made this method to enable and disable refreshing.
private void setToRefresh(boolean refresh) {
if (refresh) {
mSwipeRefreshLayout.setEnabled(true);
mSwipeRefreshLayout.setRefreshing(true);
} else {
mSwipeRefreshLayout.setRefreshing(false);
mSwipeRefreshLayout.setEnabled(false);
}
}

Create splash screen in the same Activity

I need to show splash layout file until operation is completed and than change to main layout.
Here is an example .
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash_screen);
//Here app is copying files or something other it doesn't mater.
RelativeLayout panel = new RelativeLayout(this);
//Here is creating of main layout
setContentView(panel);
I need to show splash screen while operations are performing (between two methods setContentView) And than I need to set main layout,
I have tried to do in this way but it shows only black screen and only than shows main layout (panel).
Where is the problem ?
Thx for help in advance.

You can do something like this, if you're not doing heavy stuff precisely on setContentView(R.layout.main)
public void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
handler = new Handler();
new AsyncTask<Void, Void, Void>() {
#Override
protected Void doInBackground(Void... params) {
//Do some heavy stuff
return null;
}
#Override
public void onPostExecute(Void result){
handler.post(new Runnable(){
#Override
public void run(){
setContentView(R.layout.main);
}
});
}
}.execute();
}
EDIT You can check this True SplashScreen

Here is a sample taken from my project:
Layout page, you can customize the progress bar as you want:
`
<ProgressBar
android:id="#+id/inquiry_progress"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:layout_gravity="center"
android:visibility="gone"
android:indeterminateDrawable="#drawable/loading_progress"></ProgressBar>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:layout_gravity="center_horizontal|center_vertical"
android:id="#+id/panel_inquiry"
>
.....
</FrameLayout>
`
Java source code:
private ProgressBar progressBar;
private FrameLayout inquiryFrame;
inquiryFrame=(FrameLayout)findViewById(R.id.panel_inquiry);
progressBar=(ProgressBar)findViewById(R.id.inquiry_progress);
In order to show the splash screen/do work in background
private void callService() {
progressBar.setVisibility(View.VISIBLE);
inquiryFrame.setVisibility(View.GONE);
new ServerReqAsync().execute(this
, ServiceConstants.getRequestList());
}
When background job completed, just view the activity default layout
progressBar.setVisibility(View.GONE);
inquiryFrame.setVisibility(View.VISIBLE);
Thanks

handle emptylist and asynctask

I use useful guide written by Cyril Mottier there empty state of ListView inflate in ViewStub with id #android:id/empty. In this method all good, but if i have ListActivity without attached Adapter via setListAdapter or attached empty Adapter then i see empty view. It's all clear but if i want realize logic like this:
Open ListActivity
Attach adapter
Execute AcyncTask and get data for Adapter, show progress dialog
Call notifyDataSetChanged
dismiss dialog
Then from 1 to 3 steps i look empty view with error (e.g. "not found"). But I want show error only after execute AsyncTask. While during executing AsyncTask i want show only process dialog. I try play around use visibility option of #android:id/empty, try use include in xml. But can't realize this logic. Any suggestion would appreciate.
UPD: More information
I have activity.xml:
<FrameLayout
android:id="#id/gd_action_bar_content_view"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1" >
<ListView
android:id="#android:id/list"
style="#style/listViewStyle"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:focusable="false" />
<ViewStub
android:id="#android:id/empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
layout="#layout/error" />
</FrameLayout>
error.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:orientation="vertical"
android:padding="20dp">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:scaleType="centerInside"
android:src="#drawable/ic_cheese" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="8dp"
android:layout_gravity="center_horizontal"
android:gravity="center"
android:textStyle="bold"
android:textSize="16sp"
android:text="#string/no_cheese" />
</LinearLayout>
ListActivity Class:
public class MyListActivity extends ListActivity implements OnScrollListener, OnItemClickListener{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity); //inflate activity with ViewStub
mAdapter = new MyAdapter(this, Collections.EMPTY_LIST);
setListAdapter(mAdapter);
new SearchAndFill().execute("");
}
}
And Async class:
private class SearchAndFill extends AsyncTask<String, Void, List<Object>>{
LoadingDialog dialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
if (dialog==null){
dialog = new LoadingDialog(MyListActivity.this);
dialog.setCancelable(false);
}
dialog.show();
}
#Override
protected List<Object> doInBackground(String... str) {
return search(str[0]); //this is HTTP GET request
}
#Override
protected void onPostExecute(List<Object> result) {
super.onPostExecute(result);
dialog.dismiss();
showResult(result); //this is fill adapter data and call notifyDataSetChanged
}
}
When activity create and inflate activity.xml it's show empty with and then execute AsyncTask, while AsyncTask executing i see empty view. When call onPostExecute method of AsyncTask i see result of HTTP GET request. When activity creating and inflated activity.xml it's show empty with and then execute AsyncTask, while AsyncTask executing i see empty view. When call onPostExecute method of AsyncTask i see result of HTTP GET request. I think it's wrong. I want show blank ListView before AsyncTask executed, and after if result equals Collections.EMPTY_LIST i want show text with image (e.g nothing found)

As much as I understood this is what you want to achieve...
public class MyListActivity extends ListActivity implements OnScrollListener, OnItemClickListener{
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity); //inflate activity with ViewStub
((ViewStub) findViewById(R.id.YOUR_VIEW_STUB_ID)).setVisibility(View.GONE);
mAdapter = new MyAdapter(this, Collections.EMPTY_LIST);
setListAdapter(mAdapter);
new SearchAndFill().execute("");
}
}
... ... ....
private class SearchAndFill extends AsyncTask<String, Void, List<Object>>{
LoadingDialog dialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
if (dialog==null){
dialog = new LoadingDialog(MyListActivity.this);
dialog.setCancelable(false);
}
dialog.show();
}
#Override
protected List<Object> doInBackground(String... str) {
return search(str[0]); //this is HTTP GET request
}
#Override
protected void onPostExecute(List<Object> result) {
super.onPostExecute(result);
if (result == null || result.size() == 0){
mAdapter.notifyDataSetInvalidated();
((ViewStub) findViewById(R.id.YOUR_VIEW_STUB_ID)).setVisibility(View.VISIBLE);
} else {
// add stuff to mAdapter here...
mAdapter.notifyDataSetChanged();
}
dialog.dismiss();
}
}

I suggest you to try setting text value of your empty view to empty string ("") then change the text value to error message when AsyncTask is complete.
Hope it solved your problem.