Develop Reference

setVisibility(View.GONE) causes a Crash

[Edit: I have just replaced adView.setVisibility(View.GONE) with adView.setVisibility(View.INVISIBLE) the WebView loads and nothing crashes, so it really looks like it is something to do with when I remove the AdView xml element, rather than just making it invisible. Making it invisible is not ideal, as you get a white empty bar at the bottom where the Ad should have been. So it really looks like it is something to do with reloading the Webview or messing with the UI. My html/javascript code is solid and can handle any dimension changes.]
I have a Webview above a banner for an advert (the "ca-app-pub-3940256099942544/6300978111" is the test ad id, so I am not given out any personal info)
<WebView
android:id="#+id/webView"
android:layout_width="0dp"
android:layout_height="0dp"
android:layout_marginBottom="5dp"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toTopOf="#+id/adView" />
<!-- "BANNER" or "LARGE_BANNER" -->
<com.google.android.gms.ads.AdView
android:id="#+id/adView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintBottom_toBottomOf="parent"
app:adSize="BANNER"
app:adUnitId="ca-app-pub-3940256099942544/6300978111"/>
Note: the app:layout_constrain... in the Webview. I think that might be part of the problem.
At start up, I am checking for purchases. If the user has made any purchases whatsoever, I turn off the ads with the code:
public void turnAdvertsOff() {
advertsOn = false;
AdView adView = (AdView) m_Context.findViewById(R.id.adView);
adView.destroy();
adView.setVisibility(View.GONE);
}
With the line adView.setVisibility(View.GONE); the program crashes with the unfounded allegation:
I/chromium: [INFO:CONSOLE(6381)] "Uncaught Error: Java exception was raised during method invocation", source: file:///android_asset/www/index.html?IsAndroidWebview=true (6381)
D/WebView: loadUrl=about:blank
D/WebView: destroy
However, I know there is nothing wrong in the Webview, as when I hash out the line //adView.setVisibility(View.GONE);, the WebView loads fine.
Does anyone know why?
Is it anything to do with the app:layout_constraint.., and if so how do I overcome it?

This is what is recommended to hide the adView:
adView.pause();
adView.setVisibility(View.GONE);

Try using a LinearLayout as 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"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<WebView
android:id="#+id/webView"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_marginBottom="5dp"
android:layout_weight="1" />
<!-- "BANNER" or "LARGE_BANNER" -->
<com.google.android.gms.ads.AdView
android:id="#+id/adView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:adSize="BANNER"
android:layout_gravity="center"
app:adUnitId="ca-app-pub-3940256099942544/6300978111" />
</LinearLayout>
SMART_BANNER

OK, I have found the answer, and it is not obvious. It is a combination of #mTak 's answer and a critical bit of how Android apps work (which is something I did not realise since I come from an html/javascript world and multi-threading is something programmers have absolute control over in that environment).
The purchases checks were being made on another thread. So the attempt at doing adView.setVisibility(View.GONE) was causing grief to the program. It does not seem to like you messing with the UI except on the main UI thread.
So this is how I changed my code to make the Android protocols happy:
My Purchase check (in a separate thread, but in the MainActivity). Note, stringListARR is just an array of strings with the product codes that the user had purchased. So if there was at least one purchase, whatever it was, I had decided to turn off adverts:
// Any purchase means we have no adverts
myAdverts.advertsOn = stringListARR.size() > 0 ? false : true;
// This is the evil line of code that caused the problem - this was being called not on the UI thread
//if(!myAdverts.advertsOn) myAdverts.turnAdvertsOff();
// And this is how to do it properly forcing it to be run on the UI thread
// 'this' in the following is my MainActivity
if(!myAdverts.advertsOn){
this.runOnUiThread(new Runnable(){
#Override
public void run() {
myAdverts.turnAdvertsOff();
}
});
}
And #mTak was perfectly right how to do things properly. My turnAdvertsOff() looks like this:
public void turnAdvertsOff() {
advertsOn = false;
AdView adView = (AdView) m_Context.findViewById(R.id.adView);
adView.pause();
adView.setEnabled(false);
adView.setVisibility(View.GONE);
}
So thanks to #mTak and thanks to this almost unfindable thread on google which gave me the idea:
https://groups.google.com/forum/#!topic/google-admob-ads-sdk/d30EAC1zGFo
In fact, if any people here on Stackoverflow are answering questions about crashes when people are messing with the UI in Android, this runOnUiThread might be the first solution that springs to mind. It is not obvious and a pain to discover.

How to resolve method 'setText(java.lang.String)

I know this has been posted countless times and im sorry but I have tried to follow the solutions but can't seem to fix it.
Basically I'm trying to read records from Android SQLite Database, but I keep getting the error at setText.
public class Landing extends AppCompatActivity{
public Button buttonProducts;
public void countRecords(){
int recordCount = new TableControllerAppointments(this).count();
ScrollView textViewRecordCount = findViewById(R.id.textViewRecordCount);
textViewRecordCount.setText(recordCount + " records found.");
}
I'm following a tutorial and I added this code to my XML file,
<ScrollView
android:id="#+id/textViewRecordCount"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="8dp"
android:layout_marginEnd="8dp"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:padding="1dp"
android:text="#string/textViewRecordCount"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.182"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/buttonCreateAppointment"
app:layout_constraintVertical_bias="0.146" >
<LinearLayout
android:id="#+id/linearLayoutRecords"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
</LinearLayout>
</ScrollView>
Sorry if im not posting right this is my first time. I think its something to do with my ScrollView but not sure, any help would be much appreciated
Thanks

How to resolve method 'setText(java.lang.String)
FYI
setText() is method of textview not a method of Scrollview because ScrollView does not have any setText()
You can not use as Scrollview.setText("Nilesh");
textview.setText("Nilesh");

It must be like this I hope
public Button buttonProducts;
public void countRecords(){
int recordCount = new TableControllerAppointments(this).count();
TextView textViewRecordCount = findViewById(R.id.textViewRecordCount);
textViewRecordCount.setText(String.ValueOf(recordCount) + " records found.");
}
You can't set text to Scrollview, first you have to understand this, it's basic

You're trying to set text for "Scrollview", which is absolutely wrong. Scroll view is a view which is using for scroll the layout while the application runs. to full fill your requirement you have to declare a TextView. Then you can set the text for it.

ConstraintLayout intermittent layout failure

ConstraintLayout intermittently fails to layout correctly when a view is set from GONE to VISIBLE shortly after an activity is resumed:
<android.support.constraint.ConstraintLayout
android:id="#+id/constraint_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior">
<TextView
android:id="#+id/text1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintTop_toTopOf="parent"/>
<TextView
android:id="#+id/text2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_constraintLeft_toRightOf="#id/text1"
app:layout_constraintTop_toTopOf="parent"/>
</android.support.constraint.ConstraintLayout>
override fun onResume() {
super.onResume()
text1.text = ""
text1.visibility = View.GONE
text2.text = ""
text2.visibility = View.GONE
text1.postDelayed({
text1.text = "Hello"
text1.visibility = View.VISIBLE
text2.text = "World"
text2.visibility = View.VISIBLE
}, 100
)
}
Full source code here
Instrumenting the TextView class reveals that the TextView instances are measured correctly but their width is set to 0 when they are laid out.
I wonder if the ConstraintLayout LinearSystem is non-deterministic. Are there maps that are iterated over where the iteration order is undefined? (I've seen this with Cassowary)

I'm looking to your statement in github page:
ConstraintLayout intermittently fails to layout correctly when a view is set from GONE to VISIBLE shortly after an activity is resumed
I've checked out your project and changed 100ms to 1000ms.
Here's the output:
It seems to me, that you expect that the moment you perform textview.setVisibility(View.GONE) you expect the view to be not visible. That's not the way android works. You are merely posting an event to the MessageQueue that would be handled later by Looper, and this 100ms is not enough for human eye to see those changes happening.

This was a bug in the ConstraintLayout fixed in constraint-layout:1.1.0-beta2 https://issuetracker.google.com/issues/65613481

Android studio throws "Too much output to process error" on debug

Android studio throws "Too much output to process error" on debug.
I just started working on android development and trying to debug using my nexus 5 as a connected device.
Being a novice, I thought it was a memory issue and even closed all the background applications. In my single activity I am just displaying a background image and a button.
Please have a look at the layout xml...
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#drawable/backgroundimage"
android:weightSum="5"
android:orientation="vertical">
<LinearLayout
android:layout_height="0dp"
android:layout_width="match_parent"
android:layout_weight="1"
android:background="#C9BDBD"
android:padding="5dp">
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="20dp"
android:background="#6C7B8B"
android:textColor="#000000"
android:text="Become An Android Developer"
android:onClick="Congratulations!!! You are now initiated.."/>
</LinearLayout>

your Button's android:onClick should be a method in the Java code.
<Button
android:layout_width="match_parent"
android:layout_height="match_parent"
android:textSize="20dp"
android:background="#6C7B8B"
android:textColor="#000000"
android:text="Become An Android Developer"
android:onClick="Congratulations!!! You are now initiated.."/>
something like
android:onClick="doSomthing"/>
and in the Java code:
public void doSomthing(View v){
...
...
...
}

As far as "too much output..." issue is concerned, you can mostly ignore it. Still it would make sense if you remove some of the really unnecessary Log lines from your code, especially from methods that are called repeatedly and frequently.
Another thing, i believe you want to show a text "Congratulations!!! You are now initiated.." when user clicks on button.
So change your xml's android:onClick to android:onClick= "myButtonClicked"
In the activity, implement this function
public void myButtonClicked(){
}
Finally, show the text "Congratulations!!! You are now initiated.." either via dialog (e.g. alertDialog) or in some textView

You may have selected "No Filters" in android monitor which causes "Too much output to process error", Change it to "Show only selected Application" then all other Log line are filtered and will not show in Logcat.

Android: Inflating layout takes to long

Found a Solution!
I now use a ViewPager instead of a ViewFlipper.
The Views are now generated within my run() method (which is already there because I fetch data from the web) and saveed in a Map.
In my Handler I only call pagerAdapter.notifyDataSetChanged() the pagerAdapter uses the Map of views and it works smooth and fast.
So I'm now looking for a away to have the ViewPager scroll endless, but thats another problem not connected to this one ;)
Thank all of you for your answers and keep up the good support.
I'm quite new to Android development and facing a problem while inflating a (huge) layout.
I getting some Data from a Webservice which works fine then i'm using a handler within my Activity to bring this data to the frontend. Here is my handleMessage:
public void handleMessage(Message msg) {
LayoutInflater inflater = getLayoutInflater();
List<Integer> gamedays = new ArrayList<Integer>(games.keySet());
Collections.sort(gamedays);
for (Integer gameday : gamedays) {
View gamedaytable = inflater.inflate(R.layout.gamedaytable, null);
TableLayout table = (TableLayout) gamedaytable.findViewById(R.id.gameDayTable);
table.removeAllViews();
List<Game> gamelist = games.get(gameday);
int rowcount = 2;
for (Game game : gamelist) {
View tableRow = inflater.inflate(R.layout.gamedayrow, null);
TextView homeTeam = (TextView) tableRow.findViewById(R.id.gameDayHome);
TextView awayTeam = (TextView) tableRow.findViewById(R.id.gameDayAway);
TextView gameResult = (TextView) tableRow.findViewById(R.id.gameDayResult);
gameResult.setBackgroundResource(R.drawable.resultbackground);
homeTeam.setText(game.getHomeTeam().getName());
awayTeam.setText(game.getAwayTeam().getName());
if (game.getHomegoals() < 0 || game.getAwaygoals() < 0) {
gameResult.setText("-:-");
} else {
gameResult.setText(game.getHomegoals() + ":" + game.getAwaygoals());
}
if (rowcount % 2 == 0) {
tableRow.setBackgroundColor(0xffdee0dd);
} else {
// setting alternative background
tableRow.setBackgroundColor(0xfff1f3f0);
}
rowcount++;
table.addView(tableRow);
}
flipper.addView(gamedaytable);
}
flipper.setDisplayedChild(thisgameday - 1);
pd.dismiss();
}
My Problem is that this code runs quite slow and d the processdialog freezes for about 1 second before it disappears and the layout is shown.
games consists of 34 entries which contains 9 entries by itself.
So I'm adding 34 Views consisting of a relativeLayout () which holds the table
I think the problem is, that android starts to draw and calculte the layout and this takes too long.
If I'm correct i can not use AsynTask because i can not do UI stuff there and im doing UI stuff only.
I looking for a way to have the process dialog not freezing while doing this.
Or maybe I'm doing some completly wrong
R.layout.gamedaytable:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/relativeLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#fff1f3f0"
android:focusableInTouchMode="false" >
<TableLayout
android:id="#+id/gameDayTable"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:focusableInTouchMode="false" >
</TableLayout>
</RelativeLayout>
R.layout.gamedayrow:
<TableRow xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/tableRow1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:focusableInTouchMode="false"
android:paddingBottom="5dp"
android:paddingTop="5dp" >
<TextView
android:id="#+id/gameDayHome"
style="#style/textsizeSmallScreen"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="5dp"
android:text="Mannschaft 1" />
<TextView
android:id="#+id/textView2"
style="#style/textsizeSmallScreen"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:text=":" />
<TextView
android:id="#+id/gameDayAway"
style="#style/textsizeSmallScreen"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Mannschaft 2" />
<TextView
android:id="#+id/gameDayResult"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginLeft="10dp"
android:layout_marginRight="5dp"
android:background="#drawable/resultbackground"
android:paddingLeft="10dip"
android:text="0:5"
android:textColor="#FFFFFF"
android:textSize="11dp"
android:textStyle="bold"
android:typeface="monospace" />
</TableRow>
Additional Info:
This is how the Table should look like.
So i'm not sure if this should really be a ListView because for me its tabledata ;)
table

You seem to be building a list, you should probably look at using a ListView, which'll have the advantages of only needing to build the UI for the number of rows currently being shown, and to also do view re-use, so that you don't need to inflate as many rows.

Found a Solution!
I now use a ViewPager instead of a ViewFlipper. The Views are now generated within my run() method (which is already there because I fetch data from the web) and saveed in a Map. In my Handler I only call pagerAdapter.notifyDataSetChanged() the pagerAdapter uses the Map of views and it works smooth and fast. So I'm now looking for a away to have the ViewPager scroll endless, but thats another problem not connected to this one ;)
Thank all of you for your answers and keep up the good support.

It is better to go for Listview. Even we can add more than one design of rows in the listview in an optimized manner which will improves the performance better.

You definitely can do this on an AsyncTask. While you cannot update the UI on the doInBackground method of an AsyncTask, you can from the onProgressUpdate.
I would break up the code so you are iterating through items while in doInBackground, call publishProgress for each item, and then do the UI updates for the item when you get a callback in onProgressUpdate.