Develop Reference

How to add & stack childView to a LinearLayout?

I got The specified child already has a parent. You must call removeView() on the child's parent first. ERROR.
But I do not want to remove the parent view.
If you click a button, a message must be added at the end of LinearLayout's childViews.
This is my Java code:
Button addBTN = findViewById(R.id.addButton);
LinearLayout messageListLL = findViewById(R.id.messageList_LinearLayout);
addBTN.setOnClickListener((v) -> {
MessageItem messageItem = new MessageItem();
View messageView = View.inflate(this, R.layout.item_message, messageListLL);
messageListLL.addView(messageView, messageListLL.getChildCount());
});
This is the part of activity's xml:
<ScrollView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#id/adView"
android:layout_below="#id/userContainer"
android:background="#CCC"
android:padding="15dp">
<LinearLayout
android:id="#+id/messageList_LinearLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<Button
android:id="#+id/addButton"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:backgroundTint="#color/design_default_color_primary"
android:text="ADD"
android:textColor="#android:color/white" />
</LinearLayout>
</ScrollView>
This is item_message.xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_centerVertical="true"
android:orientation="vertical">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="left" />
<EditText
android:layout_width="300dp"
android:layout_height="wrap_content" />
<ImageView
android:layout_width="50dp"
android:layout_height="50dp"
android:layout_gravity="right"
android:background="#FFD9D9" />
</LinearLayout>
So, I'd like to make a view with item_message and put it into LinearLayout in the activity's xml, which has messageList_LinearLayout for the id attribute.
The button is also in the LinearLayout. The button must be placed at the end of the LinearLayout.
And whenever, I click the button, a message view must be created and added at the end of the messageList and also before the button.

You can just change the third parameter into null.
View messageView = getLayoutInflater().inflate(this, R.layout.item_message, null);
messageListLL.addView(messageView, messageListLL.getChildCount() - 1)
The third parameter specifies its root view. You can inflate the messageView without any roots.

Android: Custom FlowLayout

I want to make this kind of menu of tags in android. Fill layout dynamically and align to center.
How can I do that?
Edited using library recommended by #Dory
<FlowLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:f="http://schemas.android.com/apk/res-auto"
android:orientation="horizontal"
f:debugDraw="false"
f:weightDefault="0"
f:layoutDirection="ltr"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="6dip"
android:paddingTop="6dip"
android:paddingRight="12dip"
android:paddingBottom="12dip"
android:background="#android:color/black"
android:id="#+id/l_flow"/>
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginBottom="3dp"/>
Flowlayout in one xml file Button is in another xml file. I'm inflating Button then fLayout.addView(button);
what I get is this Padding top and bottom between views is higher than expected

finally I did it with help of this library. I have used only class FlowLayout and attr.xml My main.xml looks like this:
<com.example.FlowTest.FlowLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/flow"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:gravity="center_horizontal"
android:background="#android:color/white"/>
and my item layout looks like this:
<Button xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center_horizontal"
android:padding="5dp"/>
And in my Activity's onCreate method:
LayoutInflater mInflater = LayoutInflater.from(this);
mFlowLayout = (FlowLayout) findViewById(R.id.flow);
String [] names = {"goods", "shops", "cars", "washing machine","blablabla","clothes","books"};
for(int i = 0; i<names.length;i++){
Button b = (Button)mInflater.inflate(R.layout.item_flow,mFlowLayout, false);
b.setText(names[i]);
mFlowLayout.addView(b);
}

Take a look
here, you can use this library
Edit:
There is attributes provided in the where you can set horizontal and verticalspacing of the Flow Layout. See below sample xml :
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:f="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FlowLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
f:horizontalSpacing="5dp"
f:verticalSpacing="5dp" />
</RelativeLayout>
Happy coding :)

How can we hide include layout programmatically in Android?

I have to include one layout in my application. So that I have used
<include
android:id="#+id/support_layout"
android:width="match_parent"
android:height="match_parent"
layout="#layout/support"/>
I have referenced this include tag in my java file using View.
View v = (View) findViewById(R.id.support_layout);
But at some point of my code I have to Hide this layout.
so that I used v.GONE
But it's not Hiding.
I want to reference those text and button attributes located in XML programatically.
How can I do that?
There is my support.xml:
<LinearLayout
android:id="#+id/support_layout"
android:width="match_parent"
android:height="match_parent">
<TextView
android:id="#+id/txt"
android:width="match_parent"
android:height="wrap_content"/>
<Button
android:id="#+id/btn"
android:width="match_parent"
android:height="wrap_content"
android:text="Button"/>
</LinearLayout>

Since <include/> is not a View type in android and visibility is the property of View, we can not access the visibility from included layout's reference.
However if you are using kotlin with view binding, we can get the reference of root of the included layout like binding.supportLayout.root which probably will be one of the View (ConstraintLayout, RelativeLayout, LinearLayout etc.)
Now we have reference of view means we can play with their visibility like below code.
binding.supportLayout.root.visibility = View.GONE
Hope you got the idea.

We need to see your actual implementation of hiding that View you mentioned.
But, straight from reading of your question, I presume that you've might do it the wrong way.
To hide or make a view invisible, use this:
yourView.setVisibility(View.INVISIBLE);
Bear in mind that this does not remove the view compeletly; it would still remain in your layout and you could get a reference to it or even try to manipulate it.
To remove it compeletly, use this instead:
yourView.setVisibility(View.GONE);
Now if you call this, yourView would be compeletly removed from the layout. You will no longer able to get a reference to it.

Put that view into a linearlayout and hide the linearlayout. It will work.
<LinearLayout
android:id="#+id/support_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" >
<include
layout="#layout/support"
android:height="match_parent"
android:width="match_parent" /> </LinearLayout>
And don't forget writing Linearlayout instead of View.
Briefly, instead of
View v = (View) findViewById(R.id.support_layout);
Do this
LinearLayout v = (LinearLayout) findViewById(R.id.support_layout);

You can hide this "included" layout with calling setVisibility() :
v.setVisibility(View.GONE)
and show it later with calling :
v.setVisibility(View.VISIBLE)
To reference button and textview from support layout you can use findViewById method on your included View (I'm not sure but I think it's even not mandatory, you can call it directly on your activity's view) :
View supportLayout = (View) findViewById(R.id.support_layout);
Textview txv = (TextView) findViewById(R.id.txt);
Button btn = (Button) findViewById(R.id.btn);
(if it's not working try with : Button btn = (Button) supportLayout.findViewById(R.id.btn);)
-- FYI --
When you give attributs to include tags it override ones of the included layout (there support_layout LinearLayout) so you don't need to do that

you must use like this includedLayoutId.viewId.visibility = View.GONE in this case you can access to included view, now for example:
loading.xml
<com.airbnb.lottie.LottieAnimationView xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/loading"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:lottie_autoPlay="true"
app:lottie_fileName="loading.json"
app:lottie_loop="true" />
in fragment_a.xml :
<include layout="#layout/loading"
android:id="#+id/anim_loading"
android:layout_width="match_parent"
android:layout_height="#dimen/_80sdp"/>
and finally use it animLoading.loading.visibility = View.GONE

Thanks to the new ConstraintLayout.
This is how I do it with widget.Group
<include
android:id="#+id/bottom_bar_action"
layout="#layout/bottom_bar_back_action"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent" />
<androidx.constraintlayout.widget.Group
android:id="#+id/bottom_bar_group"
android:layout_width="0dp"
android:layout_height="0dp"
app:constraint_referenced_ids="bottom_bar_action" />
Then you can hide the include layout by doing binding.bottomBarGroup.visibility = View.GONE. Cheers

// 1 - copy this
<?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"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context=".Add">
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="gone"
android:onClick="onclick_gone_include"/>
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="visible"
android:onClick="onclick_visible_include"/>
<LinearLayout
android:id="#+id/support_layout"
android:gravity="center"
android:layout_width="match_parent"
android:layout_height="100dp"
>
<include
layout="#layout/support"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</LinearLayout>
</LinearLayout>
//code
//2 copy this to Add cliass
//this methods on click in Add class
public void onclick_gone_include(View view) {
View v = (View) findViewById(R.id.support_layout);//view is the v
v.setVisibility(View.GONE);
}
public void onclick_visible_include(View view) {
View v = (View) findViewById(R.id.support_layout);
v.setVisibility(View.VISIBLE);
}
//3 activity that included 'support activity'
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="vertical"
android:layout_width="match_parent"
tools:context=".Add"
android:gravity="center"
android:layout_height="wrap_content">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="textview1"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="textview2"
/>
</LinearLayout>

Make programmatically added fragment clickable, uniquely identifiable

I'm running into some problems trying to figure out how to make fragments that I have programmatically added into a LinearLayout clickable. I'm using fragments because they will be in multiple activities and it was a good way for me to create a layout like this:
http://i.stack.imgur.com/P4lOG.png
But, if there's a better way to do this that would make the process of making it clickable, I'm certainly open to changing things up.
Anyway, I'm adding the fragments to the LinearLayout, jobsList, like so:
FragmentManager fragmentManager = getFragmentManager();
int count = 2;
for (int i = 0; i < count; i++) {
FragmentTransaction fragmentTransaction = fragmentManager
.beginTransaction();
Bundle bundle = new Bundle();
bundle.putInt("jobID", i + 1);
jobFragment job = new jobFragment();
job.setArguments(bundle);
fragmentTransaction.add(R.id.jobsList, job, Integer.toString(i));
fragmentTransaction.commit();
}
The count of 2 is just a placeholder for now, later there will be an arbitrary number of jobs.
Here is the layout, it's a bit of a mess but I got all the specific weights the way I wanted this way.
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/rootContainer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content" >
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".2" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/basicPort"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/background"
android:text="Port" />
<TextView
android:id="#+id/basicLoadOrEmpty"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/background"
android:text="Load/Empty" />
<TextView
android:id="#+id/basicInOrOut"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#drawable/background"
android:text="In/Out" />
</LinearLayout>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".6"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight=".333" >
<TextView
android:id="#+id/basicContainerNum"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".4"
android:background="#drawable/background"
android:text="Container #" />
<TextView
android:id="#+id/basicChassisNum"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".4"
android:background="#drawable/background"
android:text="Chassis #" />
<TextView
android:id="#+id/basicContainerType"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight=".2"
android:background="#drawable/background"
android:text="Cont. Type" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight=".333" >
<TextView
android:id="#+id/basicDirectionArrow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".2"
android:background="#drawable/background"
android:text="Direction" />
<TextView
android:id="#+id/basicCustomer"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight=".8"
android:background="#drawable/background"
android:text="Customer Location" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight=".333" >
<TextView
android:id="#+id/basicSteamshipLine"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".4"
android:background="#drawable/background"
android:text="Steamship Line" />
<TextView
android:id="#+id/basicBKG_BOL"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight=".6"
android:background="#drawable/background"
android:text="BKG-BOL#" />
</LinearLayout>
</LinearLayout>
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_weight=".2" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="#+id/basicStatus1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight=".5"
android:background="#drawable/background"
android:text="Status 1" />
<TextView
android:id="#+id/basicStatus2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_weight=".5"
android:background="#drawable/background"
android:text="Status 2" />
</LinearLayout>
</LinearLayout>
</LinearLayout>
<Space
android:layout_width="match_parent"
android:layout_height="20dp" />
</LinearLayout>
My question to you is, is it possible to make these fragments clickable and uniquely identifiable, and if so, what is the best way to go about doing that?
Thank you for your help!

What you could do is:
Modify the layout of your fragment, so it uses the RelativeLayout (now its probably LinearLayout right?). By modify I mean either use RelativeLayout INSTEAD of LinearLayout (more complicated but i think a bit better), or put your LinearLayout INSIDE RelativeLayout.
Place a view that matches in size the size of the fragment, on top of your textViews. Add an onClickListener to it that performes the code on clicks.

First - fragments are not clickable, layouts and their children are. A Fragment can handle the click action for things that occur in its layout but you do not "click" the fragment.
Second - sounds like you're confused about how to use fragments and what a Fragment actually does. A Fragment is like an Activity with some parts missing. A Fragment has its own lifecycle and can be used to perform many of the same tasks as an Activity the difference being that (1) a Fragment is "hosted" by an activity that provides the missing functions and does not run on its own (2) a Fragment can run in the background with no UI (I do not know of a background activity yet).
You do not need to/should not be using Fragments for what you are trying to do.
Your layout is really just a series of TextViews. You should be able to make that layout in XML reuse that layout file - by simply getting a LayoutInflater anywhere else in your app that you want to. If things got really crazy you could create a custom TextView class to provide detailed functionality but you should not be using 10 fragments, each with one TextView to make that layout work.

I just wanted to follow up on things in case anybody stumbles upon this answer in the future. It turns out using fragments was a bad idea. While I was able to make them clickable and identifiable through a bit of a hack job, I ran into problems later on when I was trying to fix layout issues. So, thanks to #Rarw I looked into using a LayoutInflater instead.
And that was much easier! I just made the layout xml file, used the LayoutInflater to add it to a LinearLayout and added that to the list. Makes things much easier down the road:
LayoutInflater inflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
LinearLayout container = new LinearLayout(this);
inflater.inflate(R.layout.basic, container, true);
container.setId(i);
list.addView(container, params);
container.setClickable(true);
container.setOnClickListener(this);

A hacky solution is to place a transparent button on top of the entire fragment, have the fragment extend onClickListener, and set the button's onClickListener to this.
One way to create such a button:
Use a constraintLayout as the root layout for the xml.
As the last of child of the constraintLayout, create a button, constrain it to occupy entire fragment by setting layout_constrainXXX to corner elements.
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout
xmlns:android="http://schemas.android.com/apk/res/android"
<!-- The remaining properties of the layout -->
<!-- All the children of the layout -->
<Button
android:layout_width="0dp"
android:layout_height="0dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
android:background="#00000000"
android:id="#+id/fragment_button" />
</android.support.constraint.ConstraintLayout>
Note that you can do this other ways too, such as in a RelativeLayout
Then in the java/kotlin file, extend onClickListener.
override fun onClick(p0: View?) {
// Whatever you want to do here
}
In method onActivityCreated, set the transparent button's listener as:
var button : Button = fragment_button
button.setOnClickListener(this)

Include same layout multiple times

I have a common layout (common.xml) which I want to include many times in another layout (layout_a.xml). But it only shows me just one time. Why?
common.xml
<merge xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent">
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#android:drawable/alert_light_frame">
<ImageView
android:layout_width="match_parent"
android:layout_height="150dp"
android:id="#+id/imageView"
android:src="#drawable/test"
android:scaleType="centerCrop" />
<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
android:layout_below="#+id/imageView"
android:id="#+id/textView"
android:text="test"
android:layout_marginTop="10dp"
android:layout_marginRight="10dp"
android:layout_marginLeft="10dp" />
</RelativeLayout>
</merge>
layout_a.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent">
<include layout="#layout/common" />
<include layout="#layout/common" />
</LinearLayout>

The ids when defined in XML must be unique. You are including two layouts that have views that contain the same id.
Here is how you would go about fixing it.
p.s. Unless there is more code that you are not including in your first layout file, that merge tag is useless.

As btse said, the ids in the XML must be unique.
It can be achieved in this way:
<include android:id="#+id/common1"
layout="#layout/common" />
<include android:id="#+id/common2"
layout="#layout/common" />
For information about how to access the elements inside those two included views, you can check out this blog post.

That's what I had done in my Project with Inflater.
test1is just a Layout made with a LinearLayout(Vertical) with text and a button and mainofferslayout in that case, the main layout with an image.
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_offers_display, container, false);
View inflatedLayout = inflater.inflate(R.layout.test1, (ViewGroup) view, false);
LinearLayout ll = (LinearLayout) view.findViewById(R.id.mainofferslayout);
ll.addView(inflater.inflate(R.layout.test1, (ViewGroup) view, false));
ll.addView(inflater.inflate(R.layout.test1, (ViewGroup) view, false));
ll.addView(inflater.inflate(R.layout.test1, (ViewGroup) view, false));

I fixed by setting the layout_height of the RelativeLayout to 250dp since they are overlapped.