Develop Reference

add Dynamic child views vertically to ConstraintLayout

Android ViewGroup has the following methods to add (child) Views:
I know we can easily define horizontal/vertical orientation to LinearLayout in xml/programatically and add child views, eg.
Similarly with RelativeLayout, we can use ViewGroup's addView and RelativeLayout.LayoutParams's method:
I am also aware that we can use LinearLayout as a child inside ConstraintLayout and play with it.
Is there any solid and recommended way to add child views to ConstraintLayout dynamically?
UPDATE:
Let me give a not-so-simple example which I what I want to achieve.
Suppose you have a View1, View2 and View3. All V1, V2 and V3 are aligned vertically one below another and are complex views consisting of multiple TextViews and ImageViews. Based on user action and what server sends information, I need to add multiple V1 and V2 (can be 1 pair of V1-V2 and can be 3 pairs of V1-V2)between original V2 and V3. If I am using ConstraintLayout, would it be best if I add multiple constraints programatically when I can easily use LinearLayout with vertical orientation?
Now, in terms of efficiency, performance and less-and-beautiful-code, is ConstraintLayout best for this requirement as compared to Linear Layout?

Views can be added to ConstraintLayout using addView() in the same way as you would with LinearLayout. The difference is that with ConstraintLayout the added views must be constrained. To constrain a view programmatically, use ConstraintSet.
This class allows you to define programmatically a set of constraints to be used with ConstraintLayout. It lets you create and save constraints, and apply them to an existing ConstraintLayout.
Here is a brief example:
activity_main
Define two TextViews. Center them horizontally and positioned at the top.
<android.support.constraint.ConstraintLayout
android:id="#+id/constraintLayout"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<TextView
android:id="#+id/topView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="Top View"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/bottomView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:text="Bottom View"
android:textSize="20sp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#id/topView" />
</android.support.constraint.ConstraintLayout>
This is what you will see when a new TextView ("Middle View") is added to this layout without setting constraints. Notice that the new view defaults to position (0,0).
Let's say that we want the generated middle view to be placed between the top view and the bottom view centered horizontally in the window like this:
Here is the code that will produce this result:
MainActivity.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Define the new TextView and add it to the ConstraintLayout. Without constraints,
// this view will be positioned at (0,0).
TextView middleView = new TextView(this);
middleView.setId(View.generateViewId());
middleView.setText("Middle View");
middleView.setTextSize(TypedValue.COMPLEX_UNIT_DIP, 20.0f);
ConstraintLayout layout = findViewById(R.id.constraintLayout);
ConstraintLayout.LayoutParams lp =
new ConstraintLayout.LayoutParams(ConstraintLayout.LayoutParams.WRAP_CONTENT,
ConstraintLayout.LayoutParams.WRAP_CONTENT);
layout.addView(middleView, lp);
// Move the new view into place by applying constraints.
ConstraintSet set = new ConstraintSet();
// Get existing constraints. This will be the base for modification.
set.clone(layout);
int topMargin = (int) TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
16, getResources().getDisplayMetrics());
// Set up the connections for the new view. Constrain its top to the bottom of the top view.
set.connect(middleView.getId(), ConstraintSet.TOP, R.id.topView, ConstraintSet.BOTTOM, topMargin);
// Constrain the top of the bottom view to the bottom of the new view. This will replace
// the constraint from the bottom view to the bottom of the top view.
set.connect(R.id.bottomView, ConstraintSet.TOP, middleView.getId(), ConstraintSet.BOTTOM, topMargin);
// Since views must be constrained vertically and horizontally, establish the horizontal
// constaints such that the new view is centered.
set.centerHorizontally(middleView.getId(),ConstraintSet.PARENT_ID);
// Finally, apply our good work to the layout.
set.applyTo(layout);
}

How to change view margins dynamically in "Android Flowlayout"

I have an Android Flow layout hash_tag_layout
<org.apmem.tools.layouts.FlowLayout
android:id="#+id/hash_tag_layout"
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:layout_marginBottom="#dimen/view_padding"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin">
</org.apmem.tools.layouts.FlowLayout>
The problem is I cannot change the margins on dynamically added views.
int pixels = convertDensityPixelsToPixels(5);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(ViewGroup.LayoutParams.WRAP_CONTENT, ViewGroup.LayoutParams.WRAP_CONTENT);
lp.setMargins(0,0,pixels,pixels); //<---<< This line has no effect
TextView tv1 = new TextView(ctx);
tv1.setPadding(pixels,pixels,pixels,pixels); //int left top right bottom
tv1.setBackground(ctx.getResources().getDrawable(R.drawable.hash_tag_bubble_format));//drawable
tv1.setText("# Asd");
tv1.setLayoutParams(lp);
layout.addView(tv1);
If I change hash_tag_layout layout to a regular linear layout, than I get margins!
<LinearLayout
android:id="#+id/hash_tag_layout"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal">
</LinearLayout>
So I am lead to conlude that Android Flow layout does not allow me to add margins to views added dynamically!
Any idea how to change the source code or find a way around this? Maybe add a transparent border around the dynamically added views?

Just change your LinearLayout.LayoutParams to FlowLayout.LayoutParams.
Here is an issue discussion on GitHub.
I see that you asked a question 3 years ago, but I have just faced the same problem :)

How can I make a ViewGroup child match_parent when its sibling is GONE?

I have a layout whose root ViewGroup has two children only one of which is always visible. The other child's visibility will be set at runtime to View.GONE when not applicable.
When both children are visible, the heights are set to wrap_content and the layout looks great. The problem is that I'd like to expand the visible view to match_parent when the other is gone.
Is there any way to accomplish this or the equivalent?

You can change any View's layout like this:
view.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
The constructor takes width then height as in: new LayoutParams(int width, int height).
Also there is a LayoutParams class for each type of ViewGroup. Make sure you import the one that refers your particular ViewGroup. So if your ViewGroup is a LinearLayout use:
import android.widget.LinearLayout.LayoutParams;
I tried unsuccessfully figuring this strategy out
I'm not certain where you had trouble, but this approach only requires a couple extras lines:
// When you want to show both views
view1.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT));
view2.setVisibility(View.VISIBLE);
...
// When you want to hide the second view
view1.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT));
view2.setVisibility(View.GONE);
If you hide / show the views multiple times you can save a reference to each LayoutParams object rather than repeatedly creating new objects.

Have you tried working with android:layout_weight?
I put together this small example. Below I added a picture showing both views visible (left) and how it looks like with view2 visibility set to GONE (right). As you see, view1 uses up all available space then.
<?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="match_parent"
android:orientation="vertical" >
<View
android:id="#+id/view1"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#ff0000" />
<View
android:id="#+id/view2"
android:layout_width="fill_parent"
android:layout_height="0dp"
android:layout_weight="1"
android:background="#0000ff" />
</LinearLayout>

Centering a custom view in a RelativeLayout using LayoutParams

I'm trying to center a custom view in relative layout. This image rotates so it needs to be in the center of the layout so it doesn't go out of the layout bounds. Right now its displaying in the top left corner. Here is my code:
container = (RelativeLayout) findViewById(R.id.lay_container);
bmap = BitmapFactory.decodeResource(this.getResources(), R.drawable.charlie_sheen);
rotate_view = new RotationView(this, bmap);
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.CENTER_IN_PARENT);
rotate_view.setLayoutParams(params);
container.addView(rotate_view);
Here is my relative xml layout
<RelativeLayout
android:id="#+id/lay_container"
android:layout_width="200dip"
android:layout_height="200dip"
android:layout_alignParentRight="true"
android:layout_below="#+id/txt_1"
android:layout_marginRight="45dp"
android:layout_marginTop="56dp"
android:padding="10dip" />
Do you have any ideas? I know that there is probably a simple solution to this problmem, but I can't seem to find the answer. Setting the LayoutParameter to center should center the view in the layour right?
Thanks in advance for any help or suggestions

Overall the code to add the custom view looks correct. This may be a weak suggestion, but to rule out any issues that may have been cause by the view customization you could try modifying the code in one of two ways.
Option 1: Use the explicit form of addRule(), i.e.
params.addRule(RelativeLayout.CENTER_IN_PARENT, RelativeLayout.TRUE);
Option 2: Use the explicit form of addView() and don't set the params on the view itself, i.e.
//Omit the line above this one
container.addView(rotate_view, params);
Beyond that, perhaps some insight into the custom view, specifically how it measures itself (it's not trying to fill parent is it)?
HTH

Ok Devunwired I will do that.
Here is how I am centering the image now.
1) I am centering the image in my canvas using a BitmapDrawable setGravity(Gravity.CENTER) property.
2) I'm centering the RotationView in my Relative Layout:
<RelativeLayout
android:id="#+id/image_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_below="#+id/txt_1"
android:layout_centerHorizontal="true" >
<com.mobicartel.acceldatatester.RotationView
android:id="#+id/rotate_view"
android:layout_centerInParent="true"
android:layout_height="wrap_content"
android:layout_width="wrap_content" />
</RelativeLayout>
I'll add the background and let you know. (Right now the image isn't displaying at all. Sometimes you have to take a step backward to take two in the right direction!)

FrameLayout margin not working

My layout structure is like this
LinearLayout
FrameLayout
ImageView
ImageView
FrameLayout
TextView
LinearLayout
I have set margin's for the two ImageView which are inside FrameLayout. But FrameLayout margins are discarded and it always set's the Image to top left corner. If i change from FrameLayout to LinearLayout the margin's work properly. How to handle this ?
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/inner1"
>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
>
<ImageView
android:layout_width="24px"
android:layout_height="24px"
android:id="#+id/favicon"
android:layout_marginLeft="50px"
android:layout_marginTop="50px"
android:layout_marginBottom="40px"
android:layout_marginRight="70px"
/>
<ImageView
android:layout_width="52px"
android:layout_height="52px"
android:id="#+id/applefavicon"
android:layout_marginLeft="100px"
android:layout_marginTop="100px"
android:layout_marginBottom="100px"
android:layout_marginRight="100px"
/>
</FrameLayout>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/title"
android:layout_marginLeft="10px"
android:layout_marginTop="20px"
android:textColor="#FFFFFF"
android:textSize = "15px"
android:singleLine = "true"
/>
</LinearLayout>

I had the same issue myself and noticed that setting the layout_ margins does not work until you also set your ImageView's layout gravity i.e. android:layout_gravity="top" in the XML resource file, or from code: FrameLayout.LayoutParams.gravity = Gravity.TOP;.

To make it more clear why. The FrameLayout.onLayout() call contains this (in api v2.3.4 at least):
// for each child
final LayoutParams lp = (LayoutParams) child.getLayoutParams();
final int gravity = lp.gravity;
if (gravity != -1) {
// handle all margin related stuff
So if gravity is -1, there will be no margin calculation. And the thing is, gravity in FrameLayout.LayoutParams is defined by:
gravity = a.getInt(com.android.internal.R.styleable.FrameLayout_Layout_layout_gravity, -1);
So if gravity is not set, there will be no margin calculation.

add your xml this attribute and re run
android:layout_gravity="top"
everything is Ok!
and you dont set new layout params like this;
FrameLayout.LayoutParams llp = new FrameLayout.LayoutParams(WallpapersActivity.ScreenWidth/2, layH);
use like this:
FrameLayout.LayoutParams llp = (LayoutParams) myFrameLay.getLayoutParams();
llp.height = 100;
llp.width = 100;
myFrameLay.setLayoutParams(llp);

Taken from the FrameLayout docs (link)
The size of the frame layout is the size of its largest child (plus padding), visible or not (if the FrameLayout's parent permits).
This seems to describe the fact that it'll strip margins out. Like boulder mentioned, you could try switching to padding as it can be used to produce a similar effect if done properly.
Out of curiosity, you mentioned that it does work fine when using a LinearLayout container, why the choice of FrameLayout?

Have you tried android:layout_gravity ? Try using android:padding in you ImageViews instead of android:layout_margin. AFAIK margins doesn't work properly on Frame layout. I even had to write custom layout for that purpose once. BTW, how do you want allign you ImageViews?

try setCropToPadding(true) to ImageView ,this should be helped!

you have to set your ImageView's layout gravity top i.e. android:layout_gravity="top" in the XML resource file, or from code: FrameLayout.LayoutParams.gravity = Gravity.TOP