Develop Reference

View added programatically not changing visibility after a long time not used

I have a problem I have not yet been able to understand, nor solve.
On my android project, I have a BaseActivity. There, among other functions, I decided to add a function to show or hide a loading view when necessary. It works as intended, but sometimes an error happens.
I will try to raise some important info about my project I think can be useful. My app is integrated with an external login app. I call it when the services I call need to refresh it's token. When the user logs in on the app, it calls a listener and give me back control on mine.
The problem is the next one:
I come to an activity that needs to call a service and I have the token all right, but then I lock the phone. After a long period of time, I unlock the phone and, from the same activity, I call again the service. My activity shows de loader as intended and, as my token is expired, I call the login app from it's SDK.
When I come back to my app, and I call the service I wanted successfully, the app tries to hide the loader. This is where the fail comes, as I can't change the visibility to GONE. I looked for it on the view hierarchy and find it, but with visibility = VISIBLE.
Here is the piece of code from the loader, hope someone can find where I'm making the mistake!
abstract class BaseActivity : DaggerAppCompatActivity(){
// These are the IDS of the Views I'm adding to the activity, so I can track them and change their visibility
var imgLoadingID = -1
var rvLoadingID = -1
fun showLoading() {
// If the views are added I show them
if (imgLoadingID > 0 && rvLoadingID > 0) {
val imageView = findViewById<ImageView>(imgLoadingID)
val relativeLayout = findViewById<RelativeLayout>(rvLoadingID)
relativeLayout.visibility = View.VISIBLE
imageView.visibility = VISIBLE
imageView.isClickable = false
imageView.isFocusable = false
} else {
// else I create them and show them
val imgLoading = ImageView(this)
imgLoading.id = View.generateViewId()
imgLoadingID = imgLoading.id
val maxpx = CustomUtils.ViewUtils.converIntToDps(65, this)
Glide.with(this).asGif().load(R.mipmap.loading).into(imgLoading)
val relativeLayout = RelativeLayout(this)
relativeLayout.id = View.generateViewId()
rvLoadingID = relativeLayout.id
var params = RelativeLayout.LayoutParams(maxpx, WRAP_CONTENT)
params.addRule(RelativeLayout.CENTER_IN_PARENT)
relativeLayout.addView(imgLoading, params)
relativeLayout.background = getDrawable(R.color.pure_white_97)
relativeLayout.isClickable = true
relativeLayout.isFocusable = true
findViewById<ViewGroup>(android.R.id.content).addView(relativeLayout, RelativeLayout.LayoutParams(MATCH_PARENT, MATCH_PARENT))
imgLoading.visibility = VISIBLE
}
// I lock the back button so people don't cancel my requests
esBackPressedBlocked = true
}
// Here I find the views and change their visibility.
fun hideLoading(){
if(imgLoadingID > 0 && rvLoadingID > 0) {
val imageView = findViewById<ImageView>(imgLoadingID)
val relativeLayout = findViewById<RelativeLayout>(rvLoadingID)
relativeLayout.visibility = View.GONE
imageView.visibility = View.GONE
}
esBackPressedBlocked = false
}
}
I deleted some logs I added to the whole function, but when it fails, it enters on the hideLoading() function, even on the relativeLayout.visibility = View.GONE part.
The function used to be with the Views as an whole object instead of their ids, but I found it more reliable this way, and saving the views instead of their Id's had the same problem.
My main concern is how Android manages my application while the phone is locked for this period of time (the fails happened after 8-10 hours of inactivity). I think something there can be creating this issue. I thought also about the external Login app, since it's sdk is launching their app's intent and calling me from a listener when coming back, but, since my code is being executed, I think Android it's managing my views on an strange way. Or maybe I try to hide the loading view before I'm on the resumed activity... I don't really know.
BTW, I know there are easier solutions on showing a loader, but I wanted to create it the cleanest way. If you have any cleaner approach I'm open to any solution.
If there is anything unclear let me know in the comments, and I hope my English was clear enough to express myself, it's a tricky problem that I can't understand, so it's difficult for me to explain it.
Thanks!!

Grabbing a pointer to a TextView of a tab on the action bar?

Some other users and I are developing an Android application for the Stack Exchange chat network. We're adding a tutorial for each activity to explain the UI to the user. However, we've run into a bit of a road block.
The tutorial library wants a pointer to a view (be it a TextView, ImageView, whatever) in order to get the coordinates of the view in the display so it knows where to draw the drop shadows and stuff.
We have one activity which uses the standard "Tabbed Activity" from Android Studio, so we aren't using any custom toolbars.
The action bar looks like this:
And we want to grab a pointer to the TextView on each tab that holds the title of the tab.
So for example, we want to be able to access this Textview:
We haven't been real successful in finding anything on the internet about how to do this. It appears to be relatively easy if you're using a custom toolbar, but we aren't.
Digging in the AOSP source code, we found a potential way to do it, but the fields that we needed access to were either private or otherwise unaccessible from the main activity code.
So the question is, how can we grab a pointer to that TextView? Is it even possible?

Well, it isn't pretty but we found a way to do it. Using the layout inspector in Android Device Monitor to look at the view hierarchy, we were able to grab a pointer to it in the following way.
Keep in mind:
You may need to adjust for your activity's layout
If you're using a custom toolbar there's an easier way to do this
That being said, here's what worked for this specific use case:
ViewGroup viewGroup = (ViewGroup) getWindow().getDecorView();
LinearLayout testb = (LinearLayout) viewGroup.getChildAt(0);
FrameLayout testc = (FrameLayout) testb.getChildAt(1);
ActionBarOverlayLayout testd = (ActionBarOverlayLayout) testc.getChildAt(0);
ActionBarContainer teste = (ActionBarContainer) testd.getChildAt(1);
LinearLayoutCompat testg;
if (getResources().getConfiguration().orientation == ORIENTATION_PORTRAIT)
{
ScrollingTabContainerView testf = (ScrollingTabContainerView) teste.getChildAt(2);
testg = (LinearLayoutCompat) testf.getChildAt(0);
}
else //Landscape
{
Toolbar teste2 = (Toolbar) teste.getChildAt(0);
ScrollingTabContainerView testf = (ScrollingTabContainerView) teste2.getChildAt(0);
testg = (LinearLayoutCompat) testf.getChildAt(0);
}
testg.setId(android.R.id.tabcontent);
//String IdAsString = testg.getResources().getResourceName(testg.getId());
//Log.e("TestG", IdAsString);
TutorialStuff.chatsExplorationTutorial(this, testg);
And here's the end result:

AppGyver Supersonic navigating between Views and creating duplicates

I'm using AppGyver Steroids and Supersonic to build an app and I'm having some issues navigating between views programmatically.
Based on the docs, you navigate between views like this:
var view_obj = new supersonic.ui.View("main#index");
supersonic.ui.layers.push(view_obj);
However, when I inspect things via the Chrome DevTools, it appears that a second duplicate view is created i.e. If I navigate away from the index page and then navigate back, I now have two index pages, instead of what [I think] should be one. It also doesn't close the previous view I was on.
How can I prevent this from happening and simply move to the existing view, instead of duplicating views? How do I close a view after I have navigated away from it?
Thanks.

The problem you're encountering is that you're creating a new supersonic.ui.View("main#index") every time you navigate. On top of this, I think you want to return to the same view when you navigate back to a view for the second time, i.e. you want the view to remain in memory even if it has been removed from the navigation stack with pop() (rather than pushing a new instance of that view). For this, you need to preload or "start()" the view, as described in the docs here.
I implemented my own helper function to make this easier; here is my code:
start = function(dest, isModal) {
var viewId=dest,
view=new supersonic.ui.View({
location: dest,
id: viewId
});
view.isStarted().then(function(started) {
if (started) {
if (isModal) {supersonic.ui.modal.show(view);}
else {supersonic.ui.layers.push(view);}
} else {
// Start Spinner
supersonic.ui.views.start(view).then(function() {
if (isModal) {supersonic.ui.modal.show(view);}
else {supersonic.ui.layers.push(view);}
// Stop Spinner
}, function(error) {
// Stop Spinner
A.error(error);
});
}
});
};
Use it like start('module#view');. As a bonus, you can pass true as the second argument and it gets pushed as a modal instead.
It checks if you've already started a view - if so, it just pushes that view back onto the stack. If not, it start()s (i.e. preloads) it, then pushes it. This ensures that the view stays in memory (with any user input that has been modified) even when you pop() it from the stack.
You have to imagine that the layer stack is actually a stack in the Computer Science sense. You can only add and remove views at the top of the stack. The consequence of this is that complex navigations such as A > B > C > D > B are difficult/hacky to do (in this case, you'd have to pop() D and C in succession to get back to B).
Views will close if you pop() them, as long as you didn't start() them. If you did, and you pop() them, they remain in memory. To kill that view, you have to call stop() on it, as described in the docs I linked above.

try
var view_obj = new supersonic.ui.View("main#index");
supersonic.ui.layers.replace(view_obj);
And take a look at supersonic.ui.layers.pop();

Thanks to LeedsEbooks for helping me get my head around this challenge. I was able to find a solution. Here is the code:
var start = function(route_str, isModal) {
var regex = /(.*?)#(.*)/g;
var match_obj = regex.exec(route_str);
var view_id_str = match_obj[2],
view_location_str = route_str,
view = new supersonic.ui.View({
location: view_location_str,
id: view_id_str
});
view.isStarted().then(function(started) {
if (started)
{
if (isModal)
{
supersonic.ui.modal.show(view);
}
else {
supersonic.ui.layers.push(view);
}
}
else
{
// Start Spinner
supersonic.ui.views.start(view).then(function() {
if (isModal)
{
supersonic.ui.modal.show(view);
}
else
{
supersonic.ui.layers.push(view);
}
// Stop Spinner
}, function(error) {
// Stop Spinner
A.error(error);
});
}
});
};
You must ensure that your route has the format module#view as defined in the documentation.
PLEASE NOTE
There seems to some problem with the supersonic ui method for starting views. If you run the following code:
supersonic.ui.views.start("myapp#first-view");
supersonic.ui.views.find("first-view").then( function(startedView) {
console.log(startedView);
});
You'll notice that your view id and location are identical. This seems to be wrong as the id should be first-view and location should be myapp#first-view.
So I decided to not use the AppGyver methods and create my own preload method instead, which I run from the controller attached to my home view (this ensures that all the views I want to preload are handled when the app loads). Here is the function to do this:
var preload = function(route_str)
{
var regex = /(.*?)#(.*)/g;
var match_obj = regex.exec(route_str);
var view = new supersonic.ui.View({
location: route_str,
id: match_obj[2]
});
view.start();
};
By doing this, I'm sure that the view will get loaded with the right location and id, and that when I use my start() function later, I won't have any problems.
You'll want to make sure that your structure.coffee file doesn't have any preload instructions so as not to create duplicate views that you'll have problems with later.
Finally, I have a view that is 2 levels in that is a form that posts data via AJAX operation. I wanted the view to go back to the previous view when the AJAX operation was complete. Using my earlier function resulted in the push() being rejected. It would be nice if AppGyver Supersonic could intelligently detect that pushing to a previous view should default to a layers.pop operation, but you don't always get what you want. Anyway, I managed to solve this using supersonic.ui.layers.pop(), which simply does what the Back button would have done.
Everything working as intended now.

WebView appears as plain white box after the second time it's been initialised

EDIT: tl;dr: WebView appears as white box, even though I appear to be setting it up correctly, and indeed it does work the first two times, but fails subsequently)
EDIT: Video showing the problem in action...
I have the following bit of code which inflates a view (Which contains a WebView) from the xml which defines it:
private void createCard(ViewGroup cvFrame, Card card) {
//... setup vairables...
cvFrame.clearDisappearingChildren();
cvFrame.clearAnimation();
try {
View cv = LayoutInflater.from(getBaseContext()).inflate(R.layout.card_back_view,
cvFrame, true);
cv.setBackgroundDrawable(Drawable.createFromStream(mngr.open(deckName + "_Card_back.png"), deckName));
TextView suit = (TextView)cv.findViewWithTag("card_back_suit");
//...setup text view for suit, this code works fine every time...
WebView title = (WebView)cv.findViewWithTag("card_back_title");
//This WebView doesn't appear to be the one which actually appears on screen (I can change settings till I'm blue in the face, with no effect)
if (title != null) {
title.setBackgroundColor(0x00000000);
title.loadData(titleText, "text/html", "UTF-8");
} else {
Log.e("CardView", "Error can't find title WebView");
}
} catch (IOException e) {
Log.e("CardView", "Error making cards: ", e);
}
}
When this method is called as part of the onCreate method in my Activity, the WebView contains the correct code, and is suitably transparent.
I have a gesture listener which replaces the contents of the ViewGroup with different content (It animates the top card off to the left, replaces the contents of the top card with card 2, puts the top card back, then replaces card 2 with card 3)
//Gesture listener event
ViewGroup cvFrame = (ViewGroup)findViewById(R.id.firstCard);
cardLoc++
cvFrame.startAnimation(slideLeft);
(onAnimationEnd code)
public void onAnimationEnd(Animation animation) {
if (animation == slideLeft) {
ViewGroup cvFrameOldFront = (ViewGroup)findViewById(R.id.firstCard);
ViewGroup cvFrameNewFront = (ViewGroup)findViewById(R.id.secondCard);
createCard(cvFrameOldFront, cards.get((cardLoc)%cards.size()));
createCard(cvFrameNewFront, cards.get((cardLoc+1)%cards.size()));
TranslateAnimation slideBack = new TranslateAnimation(0,0,0,0);
slideBack.setDuration(1);
slideBack.setFillAfter(true);
cvFrameOldFront.startAnimation(slideBack);
}
}
When the animation has happened and I replace the contents of the cards, the TextView suit is replaced fine and the code definitely passes through the code to replace the WebView contents, but for some reason I end up with a white rectangle the size and shape of the WebView, no content, no transparency.
If I change the WebView to a TextView, it's contents is replaced fine, so it's an issue that occurs only with the WebView control :S
Can anyone tell me why / suggest a fix?

It turns out the WebView doesn't get cleared down when using the LayoutInflater to replace the contents of a ViewGroup. The other controls all seem to get removed (or at least the findViewWithTag() returns the right reference for every other control). I've just added in the line cvFrame.removeAllViews() immediately before the LayoutInflater does it's stuff and that fixed the issue.
If anyone has any better explanation for this I'll throw the points their way otherwise they will just go into the ether...

By calling findViewById, you are getting a reference on the previously loaded webview do you ?
so the loadData call that fails is the second one you make on a single webview instance.
you may want to check this :
Android WebView - 1st LoadData() works fine, subsequent calls do not update display
It appears that loadData() won't load data twice... you may want to try WebView.loadDataWithBaseUri()
Hope that helps.

I had a similar problem loading several WebViews content.
It was because of a misusing of the pauseTimers function
The situation was : the first webView weren't needed anymore, conscientiously I wanted to pause it before to release it. Calling onPause() and pauseTimers()
pauseTimers being common to any web views, it broke every use of webviews occuring after that, there were displaying only white rectangles.
Maybe its not your problem here, but it's worth checking your not calling WebView.pauseTimers() somewhere.

To confirm your answer, the source code for LayoutInflater.inflate(int resource, ViewGroup root, boolean attachToRoot) does in fact internally calls root.addView() which attaches the newly inflated view at the end of the root's children instead of replacing them.
So the mystery now is why did your call to findViewWithTag() is returning the expected objects for your other widgets (which would be the top, most recently created instances), but for your WebView it was returning something else.
Is it possible that there is another object in your layout XML which shares the same "card_back_title" tag?
I was also wondering why you didn't use the more common findViewById() instead, but I am not sure whether it would make a difference.

Robotium waitForView to disappear?

I'm using robotium 3.1 and I'd like to wait for a view to disappear, is there some way I can do that easily? My current way involves a ugly busy-loop with sleeps that makes no one happy.
To clarify what I'd like to happen:
waitForView(<View>) //The view appears
//The view is visible for a few seconds
waitForViewNotThere(<View>) //waits until the view has disappeared
The view that appears doesn't contain any text or such either. Any input is very much appreciated.

This is how:
final TextView helloWorldText = solo.getText("Hello world!");
solo.waitForCondition(new Condition() {
#Override
public boolean isSatisfied() {
return helloWorldText.getVisibility() == View.INVISIBLE;
}
}, 10000);

Whatever you do you are probably going to have some sort of sleep in the loop. (If you look at robotiums source it also uses sleeps). You can keep them to a minimum by using the waitforidlesync method on instrumentation that waits for the Ui thread to become idle.

if you want to wait for a view to disappear, use solo.waitForDialogToClose(long timeout).
Parameters :
timeout - the amount of time in milliseconds to wait.
returns : true if the Dialog is closed before the timeout and false if it is not closed.