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Adding button to marker information on OSMDroid [duplicate]

Can I add Custom Control as Marker to OSMBONUSPACK?
I create some Buttons and image in Android xml file Named MyMarkerItem.xml
I would like something like MyMarker.setDesign(R.layout.MyMarkerItem);
Thanks

OK, I understand that you want the marker icon itself to be not a simple bitmap, but a layout.
What you can do is to use the marker infowindow "instead" of the marker icon.
First of all, create a new class CustomInfoWindow which inherits from MarkerInfoWindow - the default InfoWindow for Markers, and uses your own layout:
public class CustomInfoWindow extends MarkerInfoWindow {
public CustomInfoWindow(MapView mapView) {
super(my_own_layout, mapView);
}
}
CustomInfoWindow myCustomInfoWindow = new CustomInfoWindow(mapView);
Then, just after creating your Marker, do that:
Set a marker icon as a 1x1 pixel size bitmap, fully transparent: setIcon(mySmall_InvisibleIcon)
Set the marker infowindow to your own: setInfoWindow(myCustomInfoWindow)
Set the infowindow "anchor" to the most appropriate and natural position, depending on the "look" of your layout: setInfoWindowAnchor(ANCHOR_CENTER, ANCHOR_CENTER) maybe?
Force the opening of the infowindow: showInfoWindow()
All these steps are fairly simple.
But then, I guess you expect some behaviour to happen when the user will click on your layout buttons.
So, inside your CustomInfoWindow code, you will certainly have to do some work => follow this tutorial.

Markers in Osmdroid arent actually android views and therefore it's not possible to add other components into them. They are basically just an image.
Simple and suggested solution
You can add your components to a MarkerInfoWindow which is displayed after a click, though.
marker.setInfoWindow(new MarkerInfoWindow(R.layout.MyMarkerItem, mapView));
Possible "real" soluiton
If you really need such behaviour - meaning you really need multiple buttons displayed on a map as a "marker" and give the user the opportunity to click on them - it should be possible to create your own implementation of a Marker-like class. In other words, you would have to implement your own subclass of OverlayWithIW or Overlay and override (mainly) the draw method (which should draw your buttons to a canvas) and the onSingleTapConfirmed method, where you would need to detect properly on which button user clicked and call the related action. Try to go through source of the Marker class, it's a good example.
But keep in mind: this is an advanced task. Everything related to drawing on canvas can lead to performance issues if it's not done properly. There will be edge cases you'll have to cover. There may be other problems you'll need to solve and debug. I would not suggest such a solution to a beginner.

It's August 2021 and I wanted to add an arbitrary layout as my marker item. Much as the OP is asking for here.
I tried the Simple and suggested solution of https://stackoverflow.com/a/53003664/866333:
marker.setInfoWindow(new MarkerInfoWindow(R.layout.MyMarkerItem, mapView));
I get a runtime exception when I click it:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference.
I refine my layout down to a single TextView widget for arguments sake and the error persists.
I give up on that answer and attempt the accepted one: https://stackoverflow.com/a/53216542/866333
public class CustomInfoWindow extends MarkerInfoWindow {
public CustomInfoWindow(MapView mapView) {
super(my_own_layout, mapView);
}
}
CustomInfoWindow myCustomInfoWindow = new CustomInfoWindow(mapView);
Using the same my_own_layout as before, let's call it R.layout.my_info_window
I get the same error:
java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.TextView.setText(java.lang.CharSequence)' on a null object reference
I dug into the AS-reverse engineered (thanks AS) source code to discover the reason for this error is that the layout being passed to the MarkerInfoWindow super class constructor has particular id requirements.
We must have these ids in our layout: bubble_title, bubble_description, bubble_subdescription, bubble_image
Here is a minimal working example:
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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">
<TextView
android:id="#+id/bubble_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
tools:layout_editor_absoluteX="153dp"
tools:layout_editor_absoluteY="20dp" />
<TextView
android:id="#+id/bubble_description"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
tools:layout_editor_absoluteX="153dp"
tools:layout_editor_absoluteY="39dp" />
<TextView
android:id="#+id/bubble_subdescription"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
tools:layout_editor_absoluteX="153dp"
tools:layout_editor_absoluteY="58dp" />
<ImageView
android:id="#+id/bubble_image"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="#drawable/marker_cluster"
tools:layout_editor_absoluteX="145dp"
tools:layout_editor_absoluteY="76dp" />
</androidx.constraintlayout.widget.ConstraintLayout>
That works great!
I can even attempt to customise by appending another widget:
<TextView
android:id="#+id/anothertexttestview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="look ma!"
tools:layout_editor_absoluteX="153dp"
tools:layout_editor_absoluteY="125dp" />
The absoluteY is ignored and superimposed on the only text I set programmatically, the title. IOW, the widget isn't purely declarative xml. I'm afraid ConstraintLayout is after my time as a front end engineer so I'll leave it to the reader to experiment from here.

Avoid duplicating UI codes

I want to write new UI class which contain Check box and Label. At the moment there is existing UI class with same elements but their element descriptions are different. But data model for both UIs are going to be same.
So is it good practice to keep separate UI classes (by duplicating GridBagConstraints and other stuffs) for each or move common code in to abstract layer and derive description of the UI elements in the implementation level?

There are some other things that you can try, so you can avoid duplicating UI code, I'll give you 2 examples:
You can use the tag to bring the UI code inside another layout file and show it in you current layout, at the end you will be able to call it directly from your current Activity or Fragment in the same way you do with the other elements at the root of your Fragment or Activity class.
Re-using layouts
First layout file named: include_example_layout.xml
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:id="#+id/textView_includeExampleLayout_label"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
<CheckBox
android:id="#+id/checkBox_includeExampleLayout_valid"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</merge>
Second layout file named: activity_main.xml
<LinearLayout>
<include layout="#layout/toolbar_search_algolia"/>
</LinearLayout>
And from the MainActivity file you will be able to call the ids of this file include_example_layout as if they were declared directly in your activity_main file, so you will be able to reuse it.
The second one is creating a View element, this has an added advantage to the first method but is a little more complex, the thing is that you will be able to move some UI logic to the class of the new View element, for example if you want to disable the checkbox when something is happening with the information you can move thtat logic to the new view class.
Custom View
I'll no write a complete tutorial about this because it is a extense topic but I'll left some examples in other places that will help you understand the most basic concepts, there are two way in wich you can build CustomViews the first one is extending the View class that will force you to create it from scratch, but you can also extend other Views like a LinearLayout and this will help you to get started with the concept of a CustomView (is not recommended in every case, it can slow down your UI if you don't use it wisely)
Example extending LinearLayout
Example extending View

listview onclick through xml

This is more of a theoretical question, I have searched in many places, but unable to find the answer:
If i add an android:onClick tag to my ListView inside the layout file, what is the method signature I should use for my java Activity in order to correctly have it been called?
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:entries="#array/models"
android:onClick="getSpecs">
</ListView>

This is the Java method signature, but it will be fired everytime you click anywhere in the ListView. It is not an ItemClickListener, as I assume that was your intention for that XML.
public void getSpecs(View v) {
}
Note that the android:onClick XML attribute is the same as View#setOnClickListener, meaning it sets the generalized view's click listener. For buttons and such this is fine, but ListViews and other complex, nested views, there are other interfaces for catching the appropriate clicks.

Why does the method referenced by the onClick layout XML need to be public?

So for about 45 minutes I was struggling to understand why my Activity's method was not reachable even though I declared it in the Activity's Layout XML like so:
<TextView
android:id="#+id/lnk_reset_password" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:onClick="resetPassword" android:clickable="true"
android:text="Reset Password" />
And my Activity's method signature:
private void resetPassword (View v) {
//logic
}
I knew as soon as I got the error that I just need to change the access modifier to "public" but I don't understand why. Does the Layout XML get compiled outside of the scope for my activity?
Thanks,

Mohammad is correct. Private methods may only be called from within the same class, or inner classes of the same class. However, it is Android framework that is calling your resetPassword method, and so it has to be public.

Because another class needs to be able to invoke it.

Display image in popout window after button is clicked -- Android/Java

I've been searching the internet for a solution to this problem for several hours now and I can't seem to find an answer that works.
I have written an android app that uses the camera emulator in Eclipse to take a photo and save it to the sd card (path is stored using a String called "file"). What I would like to do is display the image, preferably in a sort of pop-out window, with another button that closes it and returns to the app. I expect I'll need to create another class to do this, but I am not sure all that is involved. Will I have to create another XML file to do the layout? How could I access the file and display it? I expect I'll use ImageView if I am to use another class, but other than that I'm not sure what to do.
There's not much code I can really provide that would help, other than the method which is called when the button is clicked. This part of the code works just fine, and it's simply a method that looks like this:
public void viewPhoto(file){ }
As you can see, I have nothing inside the method yet, that is why I am posting here.
I have been trying to figure this out for several hours, so I would greatly appreciate any ideas you folks might have.
EDIT: MORE INFO
Many of the suggestions I have found require the image to be stored in the "src" folder of the project. However, this photo will be taken and used all within the same program, so I'll have to be able to access it using its file path alone. I can't just state its location in the XML. I created a Dialog object within my existing code, but I'm not sure if this will work. The dialog I plan to use should be able to access the photo from the specified path that is stored in the string mentioned before.
I have been referring to the first answer in this thread: Android Image Dialog/Popup
but as you can see it requires the image to be in the src folder and specified in the XML.
SECOND EDIT:
Here is the code I currently have, both for the XML and the Java. But first I want to mention that I have two XML files--one called activity_main.xml which handles all the initial buttons, menu, etc. The second one is only for my photo (called photo_viewer.xml) and it only contains the ImageView.
photo_viewer.xml:
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/pictureViewer"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<ImageView
android:id="#+id/imageView"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="#string/viewImage" />
</RelativeLayout>
Java method to generate image:
public void viewPhoto(String file){
ImageView imageView = new ImageView(getApplicationContext());
LayoutParams lp = new LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT);
Bitmap image = BitmapFactory.decodeFile(file);
imageView.setImageBitmap(image);
RelativeLayout rl = (RelativeLayout)findViewById(R.id.pictureViewer);
rl.addView(imageView, lp);
}

you need to create a class which would extend Dialog Class.
refer this how you can create your own dialog.
How to create a Custom Dialog box in android?
then for showing image just call DialogObj.show() to show dialog.