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Google Maps which extends Base Activity can't inflate map fragment

I believe it is possible to setContentView() to a map fragment while extending AppCompatActivity. However I need to extend a Base Activity which extends AppCompatActivity. This means that I need to inflate my map fragment with a container.
Unfortunately it throws this exception every time:
Caused by: android.view.InflateException: Binary XML file line #7: Class is not a View com.google.android.gms.maps.SupportMapFragment
Do I have to choose or is there a way to work around this problem?
I am creating an app that needs to access a map while still keep certain functions like the navigation drawer hence I have a Base Activity.

Since you didn't provided code I am just guessing here, but from the error you posted you are probably doing this in your XML:
<com.google.android.gms.maps.SupportMapFragment
android:layout_width="match_parent"
android:layout_height="match_parent"/>
SupportMapFragment isn't a view, it is fragment, so you should place it using the fragment tag, as following:
<fragment
class="com.google.android.gms.maps.SupportMapFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"/>

For anyone who still has this problem after migrating to SDK v28, here's something that might help: https://stackoverflow.com/a/34798398/4483494
Essentially, if you have already defined in your application manifest the key "com.google.android.geo.API_KEY", you should delete the key "com.google.android.maps.v2.API_KEY".

Improving performance of instantiating and inflating views used with a ViewFlipper

I am using a ViewFlipper to display all the measurements the app has made (1 measurement = 1 page element). The problem is, the performance of initializing/reloading of the content of the ViewFlipper gets very bad if there are more then 50 elements. i.e., the app gets unresponsive for about 15 seconds after it has launched. I did some logging and found out, that more than 70% of the loading time is spent on View.inflate(ctx, R.layout.view_measurement, null);
From my understanding, inflate(...) does parse the layout xml file to a View so it can be used in Java. Since the layout xml file is everytime the same, it looks to me like there is the same heavy job being done for each element over and over again. I tried many things to change this and let this happen only one time, unfortunately without success. I also tried to use and tags in the xml also but always got errors.
I know that there are better ways rather than the ViewFlipper to do this job, but as I am in a hurry everything else works fine, I would like to keep this and find a fast solution.
MainActivity.java
...
ViewFlipper viewFlipper;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
viewFlipper = (ViewFlipper)super.findViewById(R.id.measurementsViewFlipper);
int measurementsAmount = 100; //example
for(i=0; i<measurementsAmount; i++){
View measurementView = View.inflate(ctx, R.layout.view_measurement, null);
... fill the view ...
viewFlipper.add(measurementView);
}
...
}
view_measurement.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"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="center_vertical"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_vertical"
android:orientation="horizontal">
...
</LinearLayout>
</RelativeLayout>

The only way to reduce the xml inflation time is to reduce the number of views used in the xml layout. For example, just by looking at he layout you posted, you could(and should) remove the root RelativeLayout if it's just wrapping the LinearLayout. Also, using ConstraintLayout might allow you further remove ViewGroups and reduce the nesting level and the view count.
But this will still not be ok because the real problem is you are inflating a lot of views upfront. In your example if the page layout contains just 5 views you'll create 500 views in total(100 x 5). That's a lot and this is why you need to have a view recycle mechanism so you don't need to create all views upfront, just a few for the current pages.
If you want ViewFlipper's behavior, the Android SDK has a component called AdapterViewFlipper which you should use instead. It just needs an additional adapter class, to which you'll pass the measurement data and in which you'll inflate the measurement layout.

AndroidStudio : ListView and TabActivity [duplicate]

I am wondering what's the difference between #+id/android:list and #+id/list. I know the last one which is a regular id assignment but the first looks different. What makes it special?
Where I saw it:
I was studying on ListView, ListAdapter and things like that and the author define the ListView in layout xml file as below :
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
>
<ListView
android:id="#+id/android:list"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
/>
<TextView
android:id="#+id/android:empty"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="#string/main_no_items"/>
</LinearLayout>
and also let me mention #+id/android:empty id as well.
And he also extends ListActivity class.
Here is the source of the article.
And also what's in my mind as questions are :
Should we extend ListActivity? Maybe I want an Activity which also contains other Views.
We use #+id/android:list just because we extend ListActivity or we can use the same convention if we extend Activity?
Thanks.

Resource IDs in Android are specific to a package (which is good, or else you'd have lots of conflicts if your app is dealing with several packages at the same time).
#+id/list will create a resource ID in your app (=your package) with the name "list" and give it a unique ID. In code, that would be R.id.list.
#android:id/list will use the ID "list" from the package android (which, in code, would be android.R.id.list.
EDIT: Need to add the corrections David Hedlund pointed out: The proper reference would be #android:id/list. Also, + indicates you're defining a new ID - you obviously don't need that when you're referencing something that was defined in the Android API.

I think the example code you posted has a typo, so it should be #android:id/list (without the +). From the ListActivity javadoc:
your own view MUST contain a ListView object with the id "#android:id/list"
#android:id/list is specific to ListActivity, so you do not need it if you are adding a ListView into any other kind of Activity. You should extend ListActivity if you want the user to do more than view the list. For example, you can override ListActivity.onListItemClick to respond to clicks on an item in the list.
Similarly, #id/android:empty (again, without the +), is a special case for ListActivity. This allows you to specify an alternative view that should be displayed when your list is empty. That View will not be displayed when the list is populated.

in android,
In XML: #[package:]layout/filename
like
android:id="#+id/android:list"
This is the standard way to refer to a list view when refering to listFragment or listActivity
so filename is android:list is a reference to ListView.
navigate to res/values/ids.xml
you will find <item type="id" name="list" />
ListView is a view group that displays a list of scrollable items. The list items are automatically inserted to the list using an Adapter that pulls content from a source such as an array or database query and converts each item result into a view that's placed into the list.

Can multiple android views be stored in the same .xml file without belonging to the same parent?

I have an android project that has several small views which I need to instantiate at runtime. I haven't been able to figure out a way to store all of these related views in a single xml file and I now there are going to be many of these xml files. I was just wondering if there is any way to have them all in a single file, but not belonging to some parent ViewGroup.
The layout folder in android kinda sucks since there's no way to make subfolders, everything is just piled into the same place, ugh.
I hope someone can tell me of a better way of organizing these things.

If I understand you correctly you want several views meged onto one screen or merged into one xml file. You can include other xml's into one.
The articles showed you how to use the tag in XML layouts,
to reuse and share your layout code. This article explains the tag and how it complements the tag.
http://developer.android.com/resources/articles/layout-tricks-merge.html
Also, this video might help (about 19 minutes in). Shows you how to extract a current layout and be able to include it in others.

a couple things:
Yes, the layout folder is a pain. I use strict naming conventions to make it bearable, and in eclipse use the shortcut ctrl + shift + r to quickly find the layout I am looking for. Try naming your layouts after your activity: activity1_menu_overlay and activity1_main. With the above shortcut, just type out Activity1 and it will only show you the relevant layouts.
And if that doesn't work, you can try wrapping all your views in LinearLayouts and using view.setVisibility(View.Gone); or view.setVisibility(View.Visible); to show/hide the appropriate views.
Here is an example of that second one, because it's tough to explain.
one XML file:
<LinearLayout>
<LinearLayout ... android:visibility="visible">
<copy/paste of view 1>
</Linearlayout>
<Linearlayout ... android:visibility="gone">
<copy/paste of view 2>
</Linearlayout>
<Linearlayout ... android:visibility="gone">
<copy/paste of view 3>
</Linearlayout>
<Linearlayout ... android:visibility="gone">
<copy/paste of view etc.>
</Linearlayout>
</Linearlayout>
keep in mind this approach will require you to define a reference to each "child" LinearLayout view in your activity, so you can call setVisiblity appropriately.
This approach works well for animations, and I would only use it for 2 or 3 possible views in one xml file.

Load partial XML layout into ready layout for android

I am attempting to create a program with a set of dynamically loaded layout "pages". I have the base layout created with a minimal default skeleton of the Views common to each page. For each page I was going to hard code all the views to be swapped (:facepalm). My next thought was to create a text file and put the necessary data in a well formatted design. Only then I realized that's exactly what the XML files are. So what I would like to do is create an XML file of the pages with the data exactly as it would appear in the original layout file. Then as each page is loaded (possibly unload another page), pull the XML data for that page and insert it into the current base layout structure.
My page data
<?xml version="1.0" encoding="utf-8"?>
<pageList>
<page:1>
<Button .../>
<EditText .../>
</page>
<page:2>
...
</pagelist>
The base XML layout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent" android:weightSum="1">
<LinearLayout android:id="#+id/linearLayout1"
android:layout_width="match_parent" android:layout_height="wrap_content"
android:layout_weight="1.00" android:weightSum="1">
<EditText android:id="#+id/editText1" android:inputType="textMultiLine"
android:layout_width="0dp" android:layout_weight="0.30"
android:layout_height="match_parent"></EditText>
<RelativeLayout android:layout_width="0dp"
android:id="#+id/orientationLayout" android:layout_weight="0.70"
android:layout_height="match_parent">
<dynamically insert my PAGE here>
I am new to Android programming and have only a little experience in generating interfaces from XML. In programming C# and XML for a previous job, I would have to pull the data directly from an embedded XML file and use that to create the Button or TextBox myself. Do I need to do similar in this case or is there a way to automatically load it?
I have looked this up for a while and most answers I found on this site and other places are from months ago or longer. Those answers tend to range from IMPOSSIBLE to do it yourself. I'm hoping maybe in the past few months there might have been a change to the system I have yet to find.

You are probably looking for a ViewStub.
A ViewStub is an invisible, zero-sized View that can be used to lazily
inflate layout resources at runtime. When a ViewStub is made visible,
or when inflate() is invoked, the layout resource is inflated. The
ViewStub then replaces itself in its parent with the inflated View or
Views. [...]
You can use this like a normal view in your layout and use findViewById() to reference it in code. After that use ViewStub.setLayoutResource() to set layout that you want to show and call ViewStub.inflate() to show it. This way you can write a normal XML
layout file for every (sub-)page you need.
Also see this article.
Edit: Or probably not, I have to mention that the stub gets removed from the view hierachy after inflating. So, depends on your actual use case if this is helpful.