Develop Reference

Using Street View VR in my app

I'm using Android Studio and trying to show some chosen Street View paths in VR. I already have Street View running well and now I'm trying to show it in VR.
I have put the com.google.vr.sdk.widgets.pano.VrPanoramaView in the layout and, inside onCreate in my class, referenced it to a VrPanoramaView variable through findViewById. Now I'm trying to show an image calling a method which I've defined in this class, loadPanoImage. This method loads an image from the storage and shows it through loadImageFromBitmap.
The problem is that it isn't able to show anything, even though I've followed a guide and I've done everything as showed. I've even tryed calling it in different parts of the code (before doing any other action, on clicking a button, before and after showing streetview) but I can't understand why it isn't working and how will I be able to use it to show images taken from StreetView (I don't know if I will be able to do it dinamically or I should download them and put them in the storage).
I'm putting part of the code for reference:
public class VrExperience extends FragmentActivity {
Button buttonCitta;
Button buttonMare;
Button buttonMontagna;
TextView titleTextView;
// George St, Sydney
private static final LatLng SYDNEY = new LatLng(-33.87365, 151.20689);
// LatLng with no panorama
private static final LatLng INVALID = new LatLng(-45.125783, 151.276417);
//VrPanoramaView is inserted in the layout
private VrPanoramaView panoWidgetView;
//StreetViewPanorama is another class in my project which shows Street View
private StreetViewPanorama mStreetViewPanorama;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_vrexperiences);
panoWidgetView = (VrPanoramaView) findViewById(R.id.pano_view);
panoWidgetView.setEventListener(new VrPanoramaEventListener());
//download image and show it, but it doesn't show anything
loadPanoImage();
titleTextView = (TextView) findViewById(R.id.titleTextView);
buttonCitta = (Button) findViewById(R.id.buttonCitta);
buttonCitta.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (!checkReady()) {
return;
}
titleTextView.setVisibility(View.GONE);
buttonCitta.setVisibility(View.GONE);
buttonMare.setVisibility(View.GONE);
buttonMontagna.setVisibility(View.GONE);
loadPanoImage(); //it doesn't show anything
mStreetViewPanorama.setPosition(SYDNEY);
loadPanoImage(); //it doesn't show anything
}
}};
//code for buttonMontagna and buttonMare as well, it's identical
SupportStreetViewPanoramaFragment streetViewPanoramaFragment =
(SupportStreetViewPanoramaFragment)
getSupportFragmentManager().findFragmentById(R.id.streetviewpanorama);
streetViewPanoramaFragment.getStreetViewPanoramaAsync(
new OnStreetViewPanoramaReadyCallback() {
#Override
public void onStreetViewPanoramaReady(StreetViewPanorama panorama) {
mStreetViewPanorama = panorama;
// Only set the panorama to INVALID on startup (when no panoramas have been
// loaded which is when the savedInstanceState is null).
if (savedInstanceState == null) {
mStreetViewPanorama.setPosition(INVALID);
}
}
});
}
/**
* When the panorama is not ready the PanoramaView cannot be used. This should be called on
* all entry points that call methods on the Panorama API.
*/
private boolean checkReady() {
if (mStreetViewPanorama == null)
return false;
return true;
}
/**
* Called when the Animate To Invalid button is clicked.
*/
public void onGoToInvalid(View view) {
if (!checkReady()) {
return;
}
mStreetViewPanorama.setPosition(INVALID);
}
//retrieves image from the assets folder and loads it into the VrPanoramaView
private void loadPanoImage() {
VrPanoramaView.Options options = new VrPanoramaView.Options();
InputStream inputStream = null;
AssetManager assetManager = getAssets();
try {
inputStream = assetManager.open("demo2.jpg");
options.inputType = VrPanoramaView.Options.TYPE_MONO;
panoWidgetView.loadImageFromBitmap(
BitmapFactory.decodeStream(inputStream), options
);
inputStream.close();
} catch (IOException e) {
Log.e("Fail", "Exception in loadPanoImage" + e.getMessage());
}
}
#Override
protected void onPause() {
panoWidgetView.pauseRendering();
super.onPause();
}
#Override
protected void onResume() {
super.onResume();
panoWidgetView.resumeRendering();
}
#Override
protected void onDestroy() {
panoWidgetView.shutdown();
super.onDestroy();
}
}
This is my layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/vrExperienceActivity"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<com.google.vr.sdk.widgets.pano.VrPanoramaView
android:id="#+id/pano_view"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="5dip"
android:layout_weight="5"
android:scrollbars="none" />
<TextView
android:id="#+id/titleTextView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/white"
android:text="VR Experience"
android:textAlignment="center"
android:textAppearance="#android:style/TextAppearance.Large"
android:textColor="#0000F0"
android:visibility="visible" />
<Button
android:id="#+id/buttonCitta"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Città" />
<fragment
class="com.google.android.gms.maps.SupportStreetViewPanoramaFragment"
android:id="#+id/streetviewpanorama"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
EDIT: #LucioB
a) those are the places I've tried to call loadPanoImage, but neither of them showed anything. It acts as nothing happens calling that method, the program keeps going to the other tasks. I'd like for images to be shown directly in VR when a button is clicked, or if that isn't possible to add the classic cardboard button in Street View mode to pass to VR view.
b) I mean the code isn't doing what I expected it to do. I thought that once I created VrPanoramaView in the layout and used it to show an image through .loadImageFromBitmap it would have shown the image I loaded from asset (I have an image saved on the virtual SD), and that once I was able to do that for a single image I would have found a way to do it for a whole path.
The code doesn't give any exception, I think I'm making a logic mistake or I didn't understand how VR api work.
EDIT: I've found that the java code is working, the problem was in the layout which didn't permit to see VrPanoramaView because it was obscured by StreetViewPanorama

Finding out the parent of clicked element in android ListView

I'm building my first app based on material from http://javatechig.com/video/json-feed-reader-in-android.
Everything goes ok so far, but I found one bug with ListView elements, which I can not manage to resolve by myself :(
I have extended list_row_layout.xml by 2 fields:
<Button
android:layout_width="wrap_content"
android:layout_height="20dp"
android:text="komcie"
android:textSize="11sp"
android:id="#+id/loadComments"
android:layout_gravity="center|bottom"
android:background="#bbb"
android:layout_marginLeft="5dp"
android:enabled="true"
android:clickable="true"
android:onClick="clickedLoadComments"
android:elegantTextHeight="true"
android:layout_toRightOf="#id/thumbImage"
android:layout_below="#+id/content"
android:padding="1px" />
<ListView
android:id="#+id/comment_list"
android:layout_toRightOf="#id/thumbImage"
android:layout_below="#+id/content"
android:paddingTop="5dp"
android:layout_marginTop="0dp"
android:paddingLeft="5dp"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:cacheColorHint="#00000000"
android:dividerHeight="1dp"
android:focusable="false"
android:listSelector="#drawable/list_selector_flatcolor"
android:visibility="invisible" />
Button.android:onClick="clickedLoadComments" function load Json with elements into ListView/comment_list. It works quite fine. But if there are more elements than could be displayed on screen (~8 elements) there is a bug. Comments from clicked element are loaded into every 8th element in a ListView.
Some code:
public void clickedLoadComments(View v)
{
try {
View parent = (View)v.getParent();
ViewHolder t = (ViewHolder) parent.getTag();
if( parent != null ) {
this.loadCommentsForLeaf(parent);
}
}
catch (Exception e)
{
e.printStackTrace();
}
}
protected void loadCommentsForLeaf( View view )
{
String tmpUrl = "http://some.url.com/Ajax/LoadComments?lid=" + this.currentLeafInUse;
JSONObject commentsJson = this.getJSONFromUrl(tmpUrl);
this.parseJsonComments(commentsJson);
if( commentsJson != null )
this.updateCommentList(view);
}
public void updateCommentList( View view) {
commentListView = (ListView) view.findViewById(R.id.comment_list);
commentListView.setVisibility(View.VISIBLE);
CommentListAdapter cla = new CommentListAdapter(this, this.commentList.get(this.currentLeafInUse));
commentListView.setAdapter(cla);
// Set list height.
ViewGroup.LayoutParams params = commentListView.getLayoutParams();
params.height = setListViewHeightBasedOnItems(commentListView) + 20;
commentListView.setLayoutParams(params);
commentListView.requestLayout();
}
CustomListAdapter.java code is mostly the same as the one in tutorial.
I would really appreciate help as I have spent many hours figuring it out with not success :(

This is just a guess. You might post your Adapter code and your parseJsonComments also if this does not work.
The Cause:
The problem you are describing might be caused due to the recycling and the reusage of Views. Take a look at this image from http://android.amberfog.com
As you can see the 1. items is reused and becomes the 8. item after scrolling.
Let's assume that Item 1 has an OnClickListener which updates a Text of the item.
For example we set the text to "clicked" after the OnClickListener is triggered.
Because item 1 is reused to create item 8, item 8 will also display the text "clicked".
The Solution:
The usual way is to save all states/content in a List(or whatever) and update everything in the getView call. So if you want to update text:
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder;
...
holder.textView.setText(jsonTexts[position]);
...
return convertView;
}
And if you want to update an item just update the List in your Adapter which holds the content/JsonObjects(etc.) and call notifyDataSetChanged.
public void updateCommentList(JSONObject commentsJson, int position) {
// does not exist you might create something
//like that in your Adapter class
commentListAdapter.updateItem(commentsJson,position);
commentListAdapter.notifyDataSetChanged();
}

After i populate the listview i call this method:
private void registerClickCallback() {
ListView list = (ListView) findViewById(R.id.lv);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View viewClicked,
int position, long id) {
String xx = position+ ":" + id;
//then you can do what ever you want
}
});
}

How to make phone calls programmatically in Android?

I have the following layout defined in useful_numbers_item_fragment.xml:
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="#+id/call_linear_layout">
<LinearLayout
android:layout_width="0dp"
android:layout_height="wrap_content"
android:orientation="vertical">
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/useful_nums_item_name"/>
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/useful_nums_item_value"/>
</LinearLayout>
<ImageButton
android:layout_width="0dp"
android:layout_height="wrap_content"
android:src="#drawable/call"
android:id="#+id/call_btn"
android:onClick="callNumber"/>
</LinearLayout>
I dynamically populate the two text views in a class called UNItemListFragment.java
in the onCreate method:
public void onCreate(Bundle savedInstance) {
super.onCreate(savedInstance);
if (getArguments().containsKey(Constants.UNItem.GROUP_ID)) {
simpleCursorAdapter = new SimpleCursorAdapter(getActivity(), R.layout.useful_numbers_item_fragment, null,
new String[]{Constants.UNItem.NAME, Constants.UNItem.VALUE},
new int[]{R.id.useful_nums_item_name, R.id.useful_nums_item_value}, 0);
setListAdapter(simpleCursorAdapter);
getLoaderManager().initLoader(0, getArguments(), this);
}
}
For each number if i click on the button i want to make a phone call by
calling the callNumber method when the user clicks the button:
public void callNumber(View view) {
Intent callIntent = new Intent(Intent.ACTION_CALL);
TextView unItemVal = (TextView) findViewById(R.id.useful_nums_item_value);
String phoneNumber = unItemVal.getText().toString();
callIntent.setData(Uri.parse("tel:" + phoneNumber));
startActivity(callIntent);
}
It is ok when I click the first button in the list, but when I click on the other buttons
it continues calling the number defined in the first row...
Any idea how to resolve this?

The problem is that this line:
TextView unItemVal = (TextView) findViewById(R.id.useful_nums_item_value);
is executed on the activity, so the findViewById will always return the first item with that id, which is likely the first item in the list.
The best way to fix this would be to override the adapter and add a tag containing the phone number to the view. A quick way to fix this would be to tag along in the view hierarchy, like so:
public void callNumber(View view) {
if( view != null ) { // view is the button tapped
View parent = view.getParent(); // this should be the LinearLayout
if( parent instanceof LinearLayout ) {
TextView unItemVal = (TextView) ((LinearLayout)parent).findViewById(R.id.useful_nums_item_value);
if( unItemVal != null ) {
Intent callIntent = new Intent(Intent.ACTION_CALL);
String phoneNumber = unItemVal.getText().toString();
callIntent.setData(Uri.parse("tel:" + phoneNumber));
startActivity(callIntent);
}
}
}
}
This would find the parent for the button that was clicked, and then find the text-view containing the number within that ViewGroup.

Using findViewById() will return the first view in the activity or fragment with the specified id. If this is a ListView, it will correspond to the first row.
There are many ways to work around this problem. The quickest one (but certainly not the prettiest one, since it depends on the layout) would be to use findViewById() relative to the LinearLayout that contains the list item. Assuming that view is the ImageButton, it would be somthing like:
((View)view.getParent()).findViewById(R.id.useful_nums_item_value)
A more elegant solution would be to set a tag in the adapter's getView(), containing the data you need (in this case, the phone number to call).

Wrong updating TextView in Android app

I create simple Android app (https://www.linux.com/learn/docs/683628-android-programming-for-beginners-part-1) with latest Android Studio. Code:
public class test_act extends Activity {
private static final int MILLIS_PER_SECOND = 1000;
private static final int SECONDS_TO_COUNTDOWN = 30;
private android.widget.TextView countdownDisplay;
private android.os.CountDownTimer timer;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.full_act);
countdownDisplay = (android.widget.TextView) findViewById(R.id.time_display_box);
android.widget.Button startButton = (android.widget.Button) findViewById(R.id.startbutton);
startButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
try {
showTimer(SECONDS_TO_COUNTDOWN * MILLIS_PER_SECOND);
} catch (NumberFormatException e) {
// method ignores invalid (non-integer) input and waits
// for something it can use
}
}
});
}
private void showTimer(int countdownMillis) {
if(timer != null) { timer.cancel(); }
timer = new android.os.CountDownTimer(countdownMillis, MILLIS_PER_SECOND) {
#Override
public void onTick(long millisUntilFinished) {
countdownDisplay.setText("counting down: " +
millisUntilFinished / MILLIS_PER_SECOND);
}
#Override
public void onFinish() {
countdownDisplay.setText("KABOOM!");
}
}.start();
}
}
My XML:
<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" >
<TextView
android:id="#+id/time_display_box"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:layout_marginTop="60dp"
android:text="#string/_00_30"
android:textAppearance="?android:attr/textAppearanceLarge"/>
<Button
android:id="#+id/startbutton"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/time_display_box"
android:layout_centerHorizontal="true"
android:layout_marginTop="41dp"
android:text="#string/start" />
</RelativeLayout>
In emulator it's good working. But on my Galaxy S2 with CyanogenMod10.1(Android 4.2.2) app wrong updating TextView. Screenshot:
How I can resolve this problem?
upd: after screen rotate TextView is updating once.

You might want to try invalidating your layout every time it is updated. I am guessing with how often the text is being updated the phone is not having enough time to redraw the layout. This would also explain why it works when you rotate your phone, because then the layout is forced to update.
countdownDisplay.invalidate();
Let me know if that does not work.

It commonly happens when you put UI updates inside try blocks, try to avoid it or wrap with runOnUiThread.
EDIT:
Another reason - you update it to fast - you code does 1000 updates per second i dont think it can handle it.

Cannot display image correctly using custom item layout in ListView

I am using a ListView to display my custom item layout, which may contain some TextViews and an ImageView.
This is the item layout I made (post_item.xml):
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="60dip"
android:padding="5dip"
>
<TextView android:id="#+id/listItem_title"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_weight="1"
/>
<FrameLayout android:id="#+id/listItem_frameContent"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_below="#id/userStream_listItem_title"
android:layout_weight="1"
>
</FrameLayout>
</RelativeLayout>
I don't put the ImageView initially in the xml layout, but I will insert it when I need to the FrameLayout programmatically (I also put another views in it when needed). So, there will be some items which has ImageView in it and which don't.
I get the image to fill the ImageView from the Internet (through URL), decode it as Bitmap, and keep it as a Bitmap variable in a class represents the custom item layout (class PostItem).
When the activity shows for the first time it looks fine, but as I scrolled through the items then a problem showed up, the items which shouldn't show any image show the image from the other item which should, although they don't have any ImageView (because I didn't insert it).
I am using SDK 1.6 and the emulator. Haven't tried it in real device because I don't have it.
Here is my code for the Adapter:
private class PostItemAdapter extends ArrayAdapter<PostItem> {
private List<PostItem> mPostItems;
public PostItemAdapter(Context context, int textViewResourceId, List<PostItem> postItems) {
super(context, textViewResourceId, postItems);
mPostItems = postItems;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
View view = convertView;
if (view == null) {
LayoutInflater layoutInflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
view = layoutInflater.inflate(R.layout.post_item, null);
}
PostItem postItem = mPostItems.get(position);
if (postItem != null) {
final FrameLayout contentFrame = (FrameLayout) view.findViewById(R.id.listItem_frameContent);
final TextView titleTextView = (TextView) view.findViewById(R.id.listItem_title);
if (titleTextView != null) {
titleTextView.setText(postItem.getTitle());
}
if (contentFrame != null) {
if (postItem.hasImagePreview()) {
final ImageView previewImageView = new ImageView(getApplicationContext());
previewImageView.setId(LIST_ITEM_IMAGEVIEW_ID);
previewImageView.setAdjustViewBounds(true);
previewImageView.setMaxHeight(75);
previewImageView.setMaxWidth(75);
previewImageView.setImageBitmap(postItem.getImagePreview());
final RelativeLayout.LayoutParams layoutParams =
new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_TOP);
layoutParams.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
contentFrame.addView(previewImageView, layoutParams);
}
if (postItem.hasContent()) {
final TextView contentTextView = new TextView(getApplicationContext());
contentTextView.setText(postItem.getContent());
final RelativeLayout.LayoutParams layoutParams =
new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.FILL_PARENT,
RelativeLayout.LayoutParams.WRAP_CONTENT);
layoutParams.addRule(RelativeLayout.BELOW, LIST_ITEM_IMAGEVIEW_ID);
layoutParams.addRule(RelativeLayout.ALIGN_LEFT, LIST_ITEM_IMAGEVIEW_ID);
layoutParams.alignWithParent = true;
contentFrame.addView(contentTextView, layoutParams);
}
}
}
return view;
}
}
And this is the code to prepare the items:
/* inside a method to prepare the items */
mPostItems = new ArrayList<PostItem>();
for (int i=0; i<total); i++) {
/* operation to generate titleToDisplay and contentToDisplay */
/* contentToDisplay might be null */
mPostItems.add(new PostItem(
titleToDisplay,
contentToDisplay,
generateImagePreview()));
}
/* another method */
private Bitmap generateImagePreview(ActivityObject object) {
Bitmap imagePreview = null;
if (/*some condition*/) {
try {
InputStream inStream = (InputStream) (new URL("http://a1.typepad.com/6a010535617444970b0133ecc20b29970b-120si")).getContent();
imagePreview = Drawable.createFromStream(inStream, "linkHref");
}
catch (MalformedURLException ex) {
Log.e("INSIDE generateImagePreview()", ex.getMessage());
}
catch (IOException ex) {
Log.e("INSIDE generateImagePreview()", ex.getMessage());
}
catch (Exception ex) {
Log.e("INSIDE generateImagePreview()", ex.getMessage());
}
}
return imagePreview;
}
Is this the bug in the emulator or there is some mistake in my code (probably memory problem for the Bitmap)? Please help me, I'm really stuck in this. Any help or advice will be very appreciated. Thanks in advance :)

Cells get reused by lists and it looks like you are only altering your contentframe image if there is an image associated with the item. This means when there is no image and you are reusing a cell, it will just show whatever was passed in in the convert view. If there is no image then you should remove all children views of contentframe.
That said, you will likely get better responses in the future by being more concise. Putting up a bunch of code and taking a while to get to the issue makes it more of a chore to read and so fewer people will.