Develop Reference

How to inject a custom view to a viewGroup declared in an xml at runtime?

I' ve designed a xml layout-file with some standard ui-components in it. So far it works fine.
In my Java-code I've implemented a custom view which extends a SurfaceView for the purpose of animating things. Now I want to inject this custom view at runtime to the ui defined in the layout-file.
Do I have to provide for an empty view filler for that custom view in the XML?
How does this work? Can you show me a simple code snippet please ? Thanks

Use ViewGroup addView() method.
Also you can use ViewStub

You may use
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width=”match_parent”
android:layout_height=”match_parent”
android:background="#color/app_bg"
android:gravity="center_horizontal">
<include layout="#layout/titlebar"/>
where, this linearLayout is in basic layout while this layout in include is another layout file. So you can even reuse this layout multiple times.
Check examples here

this way it works, but is there any more elegant way to do this, e.g. with a ViewStub ?
// the animation-view:
final LighthouseView lighthouseView = new LighthouseView(this, controller);
controller.registerView(lighthouseView);
setContentView(R.layout.activity_lighthouse);
ViewGroup container = (ViewGroup) findViewById(R.id.lighthouse_container);
container.addView(lighthouseView, 0);
setContentView(container);

Should I be able to add placeholder text in a custom view?

I have a pretty basic custom view that consists of a 2 TextViews styled in a particular way. I'm inflating the view from the following layout:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
...
>
<TextView
android:id="#+id/text_line1"
tools:text="10"
.../>
<TextView
android:id="#+id/text_line2"
tools:text="Reviews"
.../>
</LinearLayout>
When I add this custom view to another layout in Android Studio via xml, the placeholder/tools text does not appear in the Android Studio preview. I'd like to see "10 Reviews" in the preview without actually setting the custom attributes which change these fields. I have imported the tools namespace in the layout containing the custom view.
Is there a way to do this? Am I creating this view incorrectly?

If I'm not mistaken, tools information is not preserved if you used the layout to inflate a custom view.
You can try using isInEditMode to populate the data using the informaion you get from AttributeSet

How to reference a View in another XML without including it?

My code currently requires a reference to a ListView in another XML file and activity. I have tried using the include keyword as so:
<include layout="#layout/cleareditems"/>
However, when I do this it merges the two layouts and you can see everything in clearedItems. What would I do just to reference that View and change it?
Thanks!

here is an example
<PATH_TO_YOUR_CLASS.YOUR_CLASS
android:id="#+id/search"//we give some name to it
android:layout_width="match_parent"
android:layout_height="wrap_content" />
and you should use merge tag, so the layout are not duplicated
<merge xmlns:android="http://schemas.android.com/apk/res/android">
//YOUR CUSTOM VIEW ELEMENTS, in this case its called search from above
</merge>

Sharing data with custom canvas view

I'm a beginner at android programming, so excuse me if my wording is slightly incorrect.
I have a custom canvas view along with a TextView inside a linear layout, defined in the layout file as
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
>
<TextView
android:id="#+id/blah"
android:layout_width="fill_parent"
android:layout_height="60dp"
android:gravity="top|center_horizontal"
/>
<com.*.Overlay android:id="#+id/combined"
android:layout_width="fill_parent"
android:layout_height="100dp"
/>
</LinearLayout>
I need to be able to read the text contained in the TextView from within the Overlay custom class that I created.
(The overlay class takes in 2 bitmaps and puts one on top of the other. The bitmaps used will depend on the text in the TextView.)
I considered using intents, but the Overlay class doesn't have an onCreate method.. All my code is within the onDraw method. I also added the necessary constructors.
I'm not sure what to try next, perhaps try accessing the parent linearlayout and then its child textview?
Hope I managed to explain everything in a non-confusing manner

Ok, managed to fix the issue... sort of
I found out that Views need to be contained in Activities.. so I created a new Activity with my custom view as an inner class, passed an intent with the necessary data to the activity and was able to use it successfully in my custom canvas view.
I was a bit surprised I didn't get any responses, but I guess that's because I'm new here

Android xml layout and adding a custom view written in xml

I've created a custom view XML layout resource MyView.xml. Can I refer to MyView by the XML layout file inside a second XML layout such as main.xml? If so, how?
(To be clear, I'm not looking for replies that explain how to inflate views from within my Java code, or that explain introducing Java classes in XML layout resources with <com.MyDomain.App.MyView ...> unless this helps here or to clarify that I have no other option.)

If your XML file is like /res/layout/MyView.xml you can refer to in main.xml with
<?xml version=”1.0” encoding=”utf-8”?>
...
<include layout="#layout/MyView.xml" />
...