Develop Reference

Picasso showing images after scrolling

I have a searchview and recyclerview , I share the xml code
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<SearchView
android:id="#+id/searchinput"
android:layout_width="match_parent"
android:background="#FFFFFF"
android:searchIcon="#null"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/searchinput"
android:layout_alignParentStart="true" />
</RelativeLayout>
Now I make request to web onQueryTextSubmit(String query), I call a function in my adapter class where I do the following
public void filterData(String query){
query=query.toLowerCase();
if(query.isEmpty()){
images.clear();
images.addAll(orignallist);
notifyDataSetChanged();
}
else {
// This is main function
getimages(query);
}
}
I here get images url in a separate thread from the web through jsoup and show it in the recycler view through piccaso, it works perfectly but it only shows when I scroll down a bit , I use this with piccaso in onbindviewholder()
Picasso.get().load(images.get(position)).fit().networkPolicy(NetworkPolicy.NO_CACHE, NetworkPolicy.NO_STORE).centerInside().into(holder.imageView);
How to show image without scrolling , thank you!
When search button clicked , when scrolled down a bit
Update : after adding more functions it is now showing only when the keypad pops up

Problem was that I was trying to use notifydatasetchanged() inside thread , so I passed activity to the adapter and implemented this :
activity.runOnUiThread(new Runnable() {
#Override
public void run() {
notifyDataSetChanged();
}
});
Images where showing on scrolling or keypad opening because adapter items were getting recycled

How can I make Gridview get filled AFTER save is clicked?

Im developing a contacts app, and for now Ive been trying to get this drawables from the array get uploaded into the Gridview on the main screen AFTER the save mosaic button is clicked in the mosaic creation screen.
the floating action button (red plus button) on the mosaicListScreen (main screen) leads to the MosaicCreationScreen). the user hypothetically uploads the image and enters the mosaic name then saves using the save mosaic button, as can be seen in the image here
For now, before I focus on uploading image and letting the user create their own unique mosaics (groups), Im testing the Gridview updating with some drawables, which are listed in the array as can be seen in the code below.
The issue thats occuring is as soon as the user clicks the floating action button on the main screen, it updates the gridview with the drawables listed in the array of the MosaicCreation Screen, THEN it goes to the MosaicCreationScreen, and when save mosaic button is clicked on the MosaicCreationScreen, the intent goes to the main screen as its supposed to do, except the gridview will have nothing on it.
so its like its doing the opposite of whats supposed to happen in steps.
here is my code for the two screens:
public class mosaicsListScreen extends AppCompatActivity {
public static mosaicsListScreen theScreen; //this variable is used in the MosaicCreationScreen to point to this screen to find the GridView by id
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
theScreen = this;
setContentView(R.layout.activity_mosaics_list_screen);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.createMosaicButton);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(),MosaicCreationScreen.class);
startActivity(intent);
finish();
}
});
}
}
here is the code for the MosaicCreationScreen (the one that opens after user clicks floating action button from mosaicListScreen (main screen))
public class MosaicCreationScreen extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mosaic_creation_screen);
final GridView mosaicList = (GridView) mosaicsListScreen.theScreen.findViewById(R.id.mosaicList);
mosaicList.setAdapter(new ImageAdapter(this)); //this line of code displays the mosaics on mosaicListScreen
Button saveNewMosaicButton = (Button) findViewById(R.id.saveNewMosaicButton);
saveNewMosaicButton.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
//mThumbIds.notify();
Intent intent = new Intent(getApplicationContext(), mosaicsListScreen.class);
startActivity(intent);
finish();
//mosaicList.setAdapter(new ImageAdapter(this)); //this displays the mosaics on mosaicListScreen, it logically should go here, however "this" causes an error saying ImageAdapter (android.content.Context) in ImageAdapter cannot be applied to (anonymous android.view.View.OnClickListener)
Toast.makeText(mosaicsListScreen.theScreen, "Mosaic Created!", Toast.LENGTH_SHORT).show();
}
});
/* mosaicList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Toast.makeText(mosaicsListScreen.theScreen, "", Toast.LENGTH_SHORT).show();
}
});*/
}
public class ImageAdapter extends BaseAdapter {
private Context mContext;
public ImageAdapter(Context c) {
mContext = c;
}
public int getCount() {
return mThumbIds.length;
}
public Object getItem(int position) {
return null;
}
public long getItemId(int position) {
return 0;
}
public View getView(int position, View convertView, ViewGroup parent) {
ImageView imageView = new ImageView(mContext);
imageView.setImageResource(mThumbIds[position]);
return imageView;
}
//this array holds the drawables that would appear on the Gridview
private Integer[] mThumbIds = {
R.drawable.family,
R.drawable.project
};
}
}
Here are the XML for the layouts:
content_mosaics_list_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="codesages.mosaic.mosaicsListScreen"
tools:showIn="#layout/activity_mosaics_list_screen">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceMedium"
android:text="#string/create_a_mosaic_or_pick_from_the_mosaics_created"
android:id="#+id/textView4"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:textSize="20sp" />
<ImageButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/deleteMosaicButton"
android:src="#android:drawable/ic_menu_delete"
android:clickable="true"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:contentDescription="" />
<GridView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/textView4"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="14dp"
android:id="#+id/mosaicList"
android:layout_above="#+id/textView7"
android:numColumns="auto_fit" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="#string/holdMosaictoDeleteLabel"
android:id="#+id/textView7"
android:layout_marginBottom="16dp"
android:layout_above="#+id/deleteMosaicButton"
android:layout_centerHorizontal="true" />
</RelativeLayout>
activity_mosaics_list_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:fitsSystemWindows="true"
tools:context="codesages.mosaic.mosaicsListScreen">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<android.support.design.widget.FloatingActionButton
android:id="#+id/createMosaicButton"
android:layout_width="56dp"
android:layout_height="66dp"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
android:src="#android:drawable/ic_input_add" />
<include layout="#layout/content_mosaics_list_screen" />
</android.support.design.widget.CoordinatorLayout>
activity_mosaic_creation_screen.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="codesages.mosaic.MosaicCreationScreen"
android:focusable="true">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/mosaicNametextField"
android:hint="Mosaic Name"
android:layout_marginTop="81dp"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Save New Mosaic"
android:id="#+id/saveNewMosaicButton"
android:layout_marginTop="48dp"
android:layout_below="#+id/uploadMosaicImageButton"
android:layout_centerHorizontal="true"
android:enabled="true"
android:clickable="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Upload Mosaic Image"
android:id="#+id/uploadMosaicImageButton"
android:layout_marginTop="68dp"
android:layout_below="#+id/mosaicNametextField"
android:layout_centerHorizontal="true"
android:enabled="true"
android:clickable="true" />
</RelativeLayout>
mosaicList.setAdapter(new ImageAdapter(this));
thats what appears to be creating the mosaics. if i comment this out, i wont see anything in the gridview.
however, i believe that should be inside the saveNewMosaicButton onClick, but I am getting an error that says "saying ImageAdapter (android.content.Context) in ImageAdapter cannot be applied to (anonymous android.view.View.OnClickListener)"
HERE is an image example of what the desired result should be. however whats happening right now is as ive stated, as soon as the floating action button is clicked, the mosaics are created, THEN it takes you to the creation screen, in which wehn i click save mosaics, it actually erases the mosaics...a job of the trash icon which is too soon to function for now heh.
appreciate help on this

Currently, you have
public static mosaicsListScreen theScreen;
in your first Activity which you use to fill the ListView in this first Activity. This is a dangerous approach because the Activity instance referenced by this variable may be destroyed, for example if you're doing work in your second Activity (e.g. downloading images) which uses much memory, but also if the user somehow triggers a configuration change.
As you are calling finish() after starting the second Activity, you even tell the system that the first Activity may be destroyed. The only reason you did not get a NPE is that the system destroys the finished Activity not instantly but as soon as it seems a good idea to do so.
All in all, you need a way to safely transmit information from one Activity to the other. In your case, I think you would like to send the Uri of the selected images ( or for now, send the resource id of the selected drawables). Both can be accomplished by using Intent extras.
Basically, there are two options:
use startActivityForResult() and override onActivityResult() to obtain the desired information for the first Activity
simply start the first Activity from the second Activity once you have the result and use getIntent() in the first Activity (e.g. in onCreate()) to check for results
No matter what you do, always access UI elements like the ListView in the Activity to which they belong!
If you choose the second option, your first Activity could look like this:
public class mosaicsListScreen extends AppCompatActivity {
public static final String THUMB_IDS = "someuniquestring";
private GridView mosaicList;
private ArrayList<Integer> mThumbIds;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mosaics_list_screen);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.createMosaicButton);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(),MosaicCreationScreen.class);
startActivity(intent);
finish();
}
});
fillThumbIds();
mosaicList = (GridView) findViewById(R.id.mosaicList);
// Note: Adapter code in this Activity
mosaicList.setAdapter(new ImageAdapter(this));
}
private void fillThumbIds()
{
mThumbIds = new ArrayList();
// somehow get older thumb ids if necessary (from database?)
// and add to ArrayList like this:
mThumbIds.add(R.drawable.family);
mThumbIds.add(R.drawable.project);
// assuming we transmit resource id's: use an int array with the Intent
int[] newThumbIds = getIntent().getIntArrayExtra(THUMB_IDS);
if (newThumbIds != null)
{
// loop through the array to add new thumb ids
for (int i = 0; i < newThumbIds.length; i++) {
mThumbIds.add(newThumbIds[i]);
}
}
}
// Adapter code goes here
// Note: thumbIds no longer as array but as ArrayList!
}
In the second Activity, you put the selected thumb ids as Intent extra as follows:
saveNewMosaicButton.setOnClickListener(new AdapterView.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getApplicationContext(), mosaicsListScreen.class);
// if 'myNewThumbs' is the int array with the new thumb ids
intent.putExtra(mosaicsListScreen.THUMB_IDS, myNewThumbs);
startActivity(intent);
finish();
}
});

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

Progress Bar ICS

I have an activity with a listview populated from the web.
While data is loading I would like to display a progress dialog instead of the listview.
My layout:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent" >
<ProgressBar
android:id="#+android:id/progress_large"
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center" />
<ExpandableListView
android:id="#+id/listview"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
I do this so that the progress bar shows itself (and this works):
setProgressBarVisibility(true);
However, once the listview is populated (with an AsyncTask), I'd like the progress bar to disappear which is not the case, it stays above the listview.
Here is what I did in the AsyncTask:
#Override
protected void onPostExecute(Void result) {
setProgressBarVisibility(false);
//... and some code to update UI
}

Do this in your code,
#Override
protected void onPostExecute(Void result) {
//progressBar.dismiss(); //this dismisses the progressbar
progressBar.setVisibility(ProgressBar.GONE)
//... and some code to update UI
}

Instead of having a ProgressBar in the layout, you can create a ProgressDialog in the preExecute method of the AsyncTask and dismiss the ProgressDialog in the postExecute method.

Try this:
Declare dialog: ProgressDialog dialog ;
In onPostExecute: dialog.dismiss();
hope it helps..

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.