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Constrain layout custom view not updating size after layoutParams change

I've seen similar questions but no answer has worked for me.
I'm trying to change my custom button width programmatically, but only the internal constrains change, not the container size inside my activity.
private fun setSizeButton() {
binding.container.layoutParams.width = context.dpToPx(NEW_SIZE)
requestLayout()
parent.requestLayout()
}
For extra context, the container is just a constrainLayout with a TextView inside. What I'm I missing for this custom view to adapt to the new width?
Update: I change the custom view from a ConstrainLayout to LinearLayout and it worked, so what's preventing the ConstrainLayout from adapting to the new layout params?

Android bottom sheet design

Is there any way i can design a bottom sheet fragment as follows:
I need to set the width of the bottom sheet to 1/4 of the screen. IS it possible to implement this?
Thanks for your help.

You can achieve the same result with this library. Or just make the same CornerSheetBehavior. As you can see it's just a BottomSheetBehavior with managing of translationX of view

Create a layout file for your bottom sheet as normal, and set the width to what you need:
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:map="http://schemas.android.com/apk/res-auto"
android:id="#+id/sheet_background"
android:layout_width="100dp"
android:layout_height="match_parent">
<androidx.constraintlayout.widget.ConstraintLayout
android:layout_width="100dp"
android:layout_height="match_parent"
app:layout_behavior="com.google.android.material.bottomsheet.BottomSheetBehavior"
app:behavior_peekHeight="150dp"
android:id="#+id/drag_up_from_here">
<!-- Bottom sheet contents here -->
</androidx.constraintlayout.widget.ConstraintLayout>
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Then to get it to stick to the right hand side, you can programmatically append the bottom sheet to your layout. This is how I add my bottom sheets:
val inflater = getSystemService(LAYOUT_INFLATER_SERVICE) as LayoutInflater
val bottomSheet = inflater.inflate(R.layout.bottomsheet_layout, null)
val bottomSheetBehavior = BottomSheetBehavior.from(bottomSheet.findViewById<View>(R.id.drag_up_from_here)
// Allow user to drag part of bottom sheet
bottomSheet.findViewById<LinearLayout>(R.id.drag_up_from_here).setOnClickListener {
if (bottomSheetBehavior.getState() != BottomSheetBehavior.STATE_EXPANDED) {
bottomSheetBehavior.setState(BottomSheetBehavior.STATE_EXPANDED)
} else {
bottomSheetBehavior.setState(BottomSheetBehavior.STATE_COLLAPSED)
}
}
// Create popup window
val bottomSheetPopup = PopupWindow(popupViewLower,
LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.MATCH_PARENT,
false)
// Get the view you want the bottom sheet added to
val currentView = findViewById<ConstraintLayout>(R.id.main_view)
// Display the popup window
bottomSheetPopup.showAtLocation(currentView, Gravity.BOTTOM, currentView.measuredWidth, 0)
The key for getting it on the right of the screen is this part:
bottomSheetPopup.showAtLocation(currentView, Gravity.BOTTOM, currentView.measuredWidth, 0)
Where currentView.measueredWidth is passed as the x value, moving the bottom sheet all the way to the right.
Edit: I realized you're also asking for the width to be exactly 1/4 the width of the screen. To do this, programmatically set the width of the bottom sheet layout to currentView.measuredWidth / 4. This post explains this well: Android view layout_width - how to change programmatically?

Unable to set layout width, height and weight of inflated view in XML in Android

I am developing an Android app. In my app, I need to inflate list of views dynamically. I added them and working. The problem is with setting the width and height of layout. Now I will demonstrate my problem with a simple project. Actually, my project is much more complicated than this simple project.
I am inflating views to this layout.
<LinearLayout
android:orientation="horizontal"
android:id="#+id/cm_photos_container"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</LinearLayout>
I am looping through a list of bitmap and adding view dynamically as follow
for(Bitmap bmp : bitmaps)
{
View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);
ImageView previewImageView = (ImageView)preview.findViewById(R.id.item_cm_preview_image);
previewImageView.setImageBitmap(bmp);
container.addView(preview);
}
Please note, in the above code, container is a LinearLayout added dynamically to the parent XML in the above.
container = new LinearLayout(this);
container.setOrientation(LinearLayout.HORIZONTAL);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
container.setLayoutParams(params);
parentLinearLayout.addView(container);
This is my item_cm_preview_image.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
android:layout_weight="1"
android:layout_height="400dp"
android:layout_width="0dp"
xmlns:android="http://schemas.android.com/apk/res/android">
<ImageView
android:scaleType="centerCrop"
android:id="#+id/item_cm_preview_image"
android:layout_width="match_parent"
android:layout_height="wrap_content" />
</LinearLayout>
As you can see, I set the layout height to 400dp, width 0 and layout_weight to 1 in the XML. So all image height must be same and width must be equal because of layout_weight. But the result is not as expected. You can see screenshot below.
As you can see in the screenshot, both layout_weight and height are not working for all inflated views. But if I add extra ViewGroup dynamically and inflate the view to that layout, it is working. Below is my code
//This happening in for loop
LinearLayout wrapper = new LinearLayout(this);
wrapper.setLayoutParams(new LinearLayout.LayoutParams(0,500,1));
View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);
ImageView previewImageView = (ImageView)preview.findViewById(R.id.item_cm_preview_image);
previewImageView.setImageBitmap(bmp);
wrapper.addView(preview);
container.addView(wrapper);
This is the result:
As you can see both layout_weight and height working when I use an extra dynamic linear layout. Why is setting layout weight and height in XML not working? Why second way is working? How can I set weight and height in XML layout file? Is it possible?

If you inflate layout using method
View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,null);
it skip its width and height parameters..., but if you will use:
View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,parent,false);
it should work correct, for example if you inflate view in activity as parent you can provide (ViewGroup) getView():
View preview = layoutInflater.inflate(R.layout.item_cm_preview_image,(ViewGroup) getView(), false);

Adding a custom view multiple times in a layout

I have a custom XML file. I want to repeat this in a layout (say Relative) n number of times, dynamically (obviously).
I have seen many posts, but none helped. I am not looking for a ListView or Adapters or so. It's as simple as - A RelativeLayout. Inside it, adding the custom XML one above another. Any number of times.
With a static LinearLayout (Vertical orientation), adding the view dynamically results in rendering it once, not one below another. Don't know why. Although a TextView or so do repeat one below the other in a loop inside a LinearLayout (Vertical).
Then I dynamically created the layout (Relative), and inflated the custom XML. Displayed one. When I tried for another below the first it told me to remove child's parent first (Exception). If I do that and add again, its as good as removing the first rendered view and adding it again.
So how can I get multiple views in same layout?
A rough presentation of what I've attempted:
mainLayout = (RelativeLayout)findViewById(R.id.mainlay); //Mainlayout containing some views already
params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.BELOW,R.id.sideLayout); //sideLayout is an existing LinearLayout within the main layout.
View child = getLayoutInflater().inflate(R.layout.dynamiccustomlayout,null);
RelativeLayout r1 = new RelativeLayout(this);
r1.setLayoutParams(params);
r1.addView(child);
mainLayout.addView(r1);
mainLayout.setLayoutParams(params);
mainLayout.addView( child);
/* r2 = new RelativeLayout(this);
r2.setLayoutParams(params);
r2.addView(contentLayout); [Gives exception] */

This is how it worked out for me...
Before that, the issue with android is:
If you add dynamic views inside a LinearLayout (Horizontal), they will appear horizontally with new created instances, added to the view.
However, shockingly, it's not the same in case of LinearLayout (Vertical orientation). Hence the whole mess.
Solution:
The RelativeLayout layout file was binded with the variable, somewhat like this:
customLay = (RelativeLayout) mainLay.findViewById(R.id.dynamicCustomLayout);
Then, a Dynamic RelativeLayout was created within which the former variable is added/wrapped.
customLayout = new RelativeLayout(this);
customLayout.addView(customLay);
Every layout is assigned an id:
customLayout.setId(i);
And then a loop is run (2 if conditions for i=0 and i>0)
for i>0 (indicates the 2nd dynamic layout, to be added below the first), LayoutParameter is created:
params = new RelativeLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT);
And then for i>0, using the ids of dynamic views, they are added one below the other:
//Following code below used id to place these views below each other to attain list type arrangement of views//
// i==0 for first view on top//
if (i == 0) {
params.addRule(RelativeLayout.BELOW, R.id.sideLayout);
customLayout.setLayoutParams(params);
}
// i>0 for views that will follow the first top//
else {
params.addRule(RelativeLayout.BELOW, i - 1);
customLayout.setLayoutParams(params);
}
Then added to main root layout, where all these views or cards need to be displayed:
includeLayout.addView(customLayout);
Ofcourse, the code is not just this. I have written the essential points that helped me achieve the target and that may help others in future.
So the main essence was ---
using a Dynamic RelativeLayout, to
bind the static RelativeLayout, and
assigning ids to the Dynamic RelativeLayout wrappers, and
on basis of ids use RelativeLayoutParameters to place the following
ids below the previous ones.

You have to instanciate every child by itself
View child = getLayoutInflater().inflate(R.layout.dynamiccustomlayout,null);
r1.addView(child);
View child2 = getLayoutInflater().inflate(R.layout.dynamiccustomlayout,null);
r1.addView(child2);
//ok, i do a analog thing in obne of my apps. here is the code:
public class FlxForm extends LinearLayout {
public FlxForm(Context context) {
super(context);
inflater = LayoutInflater.from(context);
inflater.inflate(R.layout.flxform, this);
this.setPadding(0, 0, 0, 0);
container = (LinearLayout) this.findViewById(R.id.flxform);
this.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,LayoutParams.WRAP_CONTENT));
//here is my funtion to calculate the items i want to add, its a little bit too complicated, but in the end it works like:
for(int i=0;i<10;i++){
View x = inflater.inflate(R.layout.dynamiccustomlayout,null);
container.addview(x);
}
}
}
XML for the Form
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/flxform"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:focusable="false"
android:background="#android:color/transparent"
android:orientation="vertical" >
</LinearLayout>
Then you can instantiate a "Form" Objekt and add it into a ScrollView

For doing this You would have to nest your RelativeLayout inside a ScrollView and Manage all the Scrolling, items adding, memory management, etc manually.
So the simple solution for adding n Number of Custom Views is to use a RecyclerView, ListView, GridView, etc with a neat CustomAdapter and Your Custom View.
Here is a nice example of using RecyclerView with custom Adapter :
http://code.tutsplus.com/tutorials/getting-started-with-recyclerview-and-cardview-on-android--cms-23465
I hope this Helps.

How to Programmatically Add Views to Views

Let's say I have a LinearLayout, and I want to add a View to it, in my program from the Java code. What method is used for this? I'm not asking how it's done in XML, which I do know, but rather, how can I do something along the lines of this sample code?
(One View).add(Another View)
Like one can do in Swing.

Calling addView is the correct answer, but you need to do a little more than that to get it to work.
If you create a View via a constructor (e.g., Button myButton = new Button();), you'll need to call setLayoutParams on the newly constructed view, passing in an instance of the parent view's LayoutParams inner class, before you add your newly constructed child to the parent view.
For example, you might have the following code in your onCreate() function assuming your LinearLayout has id R.id.main:
LinearLayout myLayout = findViewById(R.id.main);
Button myButton = new Button(this);
myButton.setLayoutParams(new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT,
LinearLayout.LayoutParams.MATCH_PARENT));
myLayout.addView(myButton);
Making sure to set the LayoutParams is important. Every view needs at least a layout_width and a layout_height parameter. Also getting the right inner class is important. I struggled with getting Views added to a TableRow to display properly until I figured out that I wasn't passing an instance of TableRow.LayoutParams to the child view's setLayoutParams.

The best way I found is to use the inflate static method of View.
View inflatedView = View.inflate(context, yourViewXML, yourLinearLayout);
where yourViewXML is something like R.layout.myView
please notice that you need a ViewGroup in order to add a view (which is any layout you can think of)
so as an example lets say you have a fragment which it view already been inflated and you know that the root view is a layout, and you want to add a view to it:
View view = getView(); // returns base view of the fragment
if (view == null)
return;
if (!(view instanceof ViewGroup))
return;
ViewGroup viewGroup = (ViewGroup) view;
View popup = View.inflate(viewGroup.getContext(), R.layout.someView, viewGroup);
EDIT:
Kotlin code for the example above (view is the getView() of a fragment)
(view as? ViewGroup)?.let {
View.inflate(context, R.layout.add_credit_card, it)
}

To add the view programmatically, you can do:
LinearLayout rlmain = new LinearLayout(this);
LinearLayout.LayoutParams llp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT,LinearLayout.LayoutParams.FILL_PARENT);
LinearLayout ll1 = new LinearLayout (this);
ImageView iv = new ImageView(this);
iv.setImageResource(R.drawable.logo);
LinearLayout .LayoutParams lp = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.MATCH_PARENT);
iv.setLayoutParams(lp);
ll1.addView(iv);
rlmain.addView(ll1);
setContentView(rlmain, llp);
You can also add any number of views.

LinearLayout is a subclass of ViewGroup, which has a method called addView. The addView method should be what you are after.

The idea of programmatically setting constraints can be tiresome. This solution below will work for any layout whether constraint, linear, etc. Best way would be to set a placeholder i.e. a FrameLayout with proper constraints (or proper placing in other layout such as linear) at position where you would expect the programmatically created view to have.
All you need to do is inflate the view programmatically and it as a child to the FrameLayout by using addChild() method. Then during runtime your view would be inflated and placed in right position. Per Android recommendation, you should add only one childView to FrameLayout [link].
Here is what your code would look like, supposing you wish to create TextView programmatically at a particular position:
Step 1:
In your layout which would contain the view to be inflated, place a FrameLayout at the correct position and give it an id, say, "container".
Step 2
Create a layout with root element as the view you want to inflate during runtime, call the layout file as "textview.xml" :
<?xml version="1.0" encoding="utf-8"?>
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
</TextView>
BTW, set the layout-params of your frameLayout to wrap_content always else the frame layout will become as big as the parent i.e. the activity i.e the phone screen.
android:layout_width="wrap_content"
android:layout_height="wrap_content"
If not set, because a child view of the frame, by default, goes to left-top of the frame layout, hence your view will simply fly to left top of the screen.
Step 3
In your onCreate method, do this :
FrameLayout frameLayout = findViewById(R.id.container);
TextView textView = (TextView) View.inflate(this, R.layout.textview, null);
frameLayout.addView(textView);
(Note that setting last parameter of findViewById to null and adding view by calling addView() on container view (frameLayout) is same as simply attaching the inflated view by passing true in 3rd parameter of findViewById(). For more, see this.)

One more way to add view from Activity
ViewGroup rootLayout = findViewById(android.R.id.content);
rootLayout.addView(view);

You guys should also make sure that when you override onLayout you HAVE to call super.onLayout with all of the properties, or the view will not be inflated!