Develop Reference

android margins not working when dynamically inserting views

I have a simple view:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:background="#drawable/contact_selected"
android:layout_marginTop="10dp"
android:layout_marginEnd="5dp"
android:orientation="horizontal"
android:padding="3dp">
<TextView
android:id="#+id/txt_title"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Billy Bob"
/>
</LinearLayout>
When I statically copy the LinearLayout markup into my main activity layout, the margins are as expected. However, when I add the view into the main activity layout dynamically, the margins are ignored. Here's how I insert the view
LayoutInflater inflater = (LayoutInflater)
getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View view = inflater.inflate(R.layout.test, null);
TextView txt_title = (TextView)view.findViewById(R.id.txt_title);
txt_title.setText("Dynamic #1");
llayout.addView(view, llayout.getChildCount()-1);
View view2 = inflater.inflate(R.layout.test, null);
txt_title = (TextView)view2.findViewById(R.id.txt_title);
txt_title.setText("Dynamic #2");
llayout.addView(view2, llayout.getChildCount()-1);
Here's what it looks like:
The container in the main layout is a LinearLayout, which is a child of a HorizontalScrollView. Any insight is appreciated.

When dynamically adding views, you shouldn't inflate the View with a null ViewGroup parent. So, in other words you should be using inflater.inflate(R.layout.test, linearLayout, false);. The parent is used when determining what type of layout parameters to generate. Pass your parent container (in this case, your linear layout), so it correctly instantiates the ViewGroup.MarginLayoutParams from your XML.

This happens because you need to give "Margin" to layouts dynamically. You can do this by creating an object of "LayoutPrams", like this:-
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
LinearLayout.LayoutParams.MATCH_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT);
layoutParams.setMargins(30, 20, 30, 0);
Here , you can set the LayoutParams to the linearlayout:
ll.addView(okButton, layoutParams);
Hope it helps.

First, you have to get display density.
related docs are https://developer.android.com/reference/android/util/DisplayMetrics.html
and get ID which you want set margin view.
for my case,
layout_login_box = (ConstraintLayout)findViewById(R.id.login_layout_box);
float density = getResources().getDisplayMetrics().density;
ConstraintLayout.LayoutParams params = (ConstraintLayout.LayoutParams)layout_login_box.getLayoutParams();
params.setMargins((int) (24 * density),0,(int) (24 * density),(int) (16 * density));
layout_login_box.setLayoutParams(params);
Also, you can change ConstraintLayout to your own view.

Inflate child with 0dp layout width & weight (programmatically)

Simple: I want to inflate parent with 1 child which has 0dp width.
Parent xml:
<com.example.KeyPad // extend LinearLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:weightSum="4" // for the children
android:layout_weight="1" // this is for its parent
android:clickable="true"
android:background="#color/MidnightBlue" >
The child class:
public class KeyButton extends RelativeLayout implements View.OnClickListener{
public KeyButton(Context c ) {
super(c);
RelativeLayout v = (RelativeLayout) LayoutInflater.from(c).inflate(R.layout.key_button, this, true);
}
}
}
which uses the R.layout.key_button xml:
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_weight="1"
android:layout_width="0dp"
android:background="#android:color/holo_red_dark"
android:layout_height="wrap_content">
<TextView ... />
</RelativeLayout>
And the child is getting added by:
Parent.addView(new KeyButton(context) );
The problem is that android:layout_weight doesn't look to take action and the layout_width of the child stays at "0dp". If I change the width to 50dp I can see the child that has been correct inflated.
Also tried to add the parameters programmatically when getting added:
KeyButton bt = new KeyButton(context);
LinearLayout.LayoutParams lp = new LinearLayout.LayoutParams(0, LinearLayout.LayoutParams.WRAP_CONTENT,1.0f);
bt.setLayoutParams(lp);
Parent.addView(bt);
How can I inflate the child with 0dp/weight? Of course as you can see I have defined the weight_sum of the parent.

You have used a LinearLayout.LayoutParams but the parent of your button are a RelativeLayout.
Try this :
KeyButton bt = new KeyButton(context);
RelativeLayout.LayoutParams lp = new RelativeLayout.LayoutParams(0, RelativeLayout.LayoutParams.WRAP_CONTENT,1.0f);
Parent.addView(bt, lp);

You can simply set the visibility property to gone or hidden by following code :
bt.setVisibility(View.GONE);
You can find more information about setting views here

Android fullscreen layout with additional layouts underneath, which are scrollable

I have a layout displaying some images and text, with buttons at the bottom.
When a button is pressed, I need to display some new information below the buttons.
So the initial content needs to remain at the same height (height of the device screen), and the new content needs to be added beneath it, allowing the user to scroll down.
When a button is pressed it will ideally need to show the new content like a page anchor, but the part I'm having difficulty is getting the initial content to be fullscreened, and maintain that size when new content is added whilst also making the whole thing scroll-able.
I have been playing with different layouts, different height parameters, android:fillViewport="true" or not etc.
I can provide some XML / further explanation if necessary. But I'm not sure whether what I am aiming to achieve is possible or not. At least I'd like to get a scrollable overall view, with the top layout as fullscreen and some layouts underneath which the user can scroll to.
image:

Try this:
Make ScrollView container and add your layout #1 into it
Set height of layout #1 into the code according per screen height
After button click add layout #2 into ScrollView
UPDATED:
Ok, I can suggest you only this solution (it worked for me in emulator).
XML:
<?xml version="1.0" encoding="utf-8"?>
<ScrollView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/scroll"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fillViewport="true">
<LinearLayout
android:id="#+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical">
<RelativeLayout
android:id="#+id/layout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#ff0000">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Button"
android:onClick="btnClick"/>
</RelativeLayout>
</LinearLayout>
</ScrollView>
Code:
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void btnClick(View v){
LinearLayout container = (LinearLayout)findViewById(R.id.container);
ScrollView scroll = (ScrollView)findViewById(R.id.scroll);
RelativeLayout layout1 = (RelativeLayout)findViewById(R.id.layout1);
RelativeLayout layout2 = new RelativeLayout(this);
LayoutParams params = new LayoutParams(LayoutParams.MATCH_PARENT, 300);
layout2.setBackgroundColor(Color.YELLOW);
layout1.getLayoutParams().height = scroll.getHeight();
scroll.setFillViewport(false);
container.addView(layout2, params);
}
}

I would create a custom ScrollView which sets the height of its first child to be its own height. This will simulate a fullscreen view while still being able to add content below it.
To handle screen size changes properly, the best is to override onSizeChanged() :
public class CustomScrollView extends ScrollView {
// ...
#Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
View view = getChildAt(0);
if (view != null)
view.setLayoutParams(new LayoutParams(LayoutParams.MATCH_PARENT, h)));
}
}

How to split Linear Layout in to two columns?

I have to split a Single Linear layout into a Two Columns(Like newspaper Columns).The linear layout contain text-view and image-view
I have taken the screen width and have divided it to half and made the TextView and ImageView to come in a first column , ie, A B C blocks in the picture below.. now the remaining TextView and 'ImageView has to go to next column like in D E F like that it goes on.So it would be helpful if anyone gives me any code or ideas to implement this.. I tried with GridView which is not suitable for my issue. Since the TextView and ImageView sizes are not definite.
I don't know how to split Liner layout.
I tried with calculating the rootlayout height
like this
linearLayout.post(new Runnable() {
#Override
public void run() {
// TODO Auto-generated method stub
int linsize=linearLayout.getHeight();
int relsize=root.getHeight();
int textsize=txt1.getHeight();
mainheight=relsize;
subheight=linsize;
Toast.makeText(getApplicationContext(), "Linerlayout "+linsize, Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), "Relative layout"+relsize, Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), "text height "+textsize, Toast.LENGTH_LONG).show();
if(mainheight==subheight)
{
Toast.makeText(getApplicationContext(), "make a new linear layout", Toast.LENGTH_LONG).show();
createsubview();
}
}
});
Screenshot

You could easily do this with nested LinearLayouts:
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal" >
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical" >
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/item" />
<TextView
android:id="#+id/text"
android:layout_width="wrap_content"
android:layout_height="wrap_content"/>
</LinearLayout>
<LinearLayout
android:layout_width="0dp"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical" >
<ImageView
content here/>
<TextView
content here/>
</LinearLayout>
</LinearLayout>
Then all that you need to do is put A, B and C in the first vertical layout, and D, E and F in the second.

You can't do it with GridView. You would have to create a custom view to do this.
if you know how big your grid items are, you can cut some corners. GridView is complicated mostly because it deals with items of any size and loads them dynamically. An easier way for you might be:
1.Create a HorizontalScrollView with a horizontal LinearLayout inside.
2.Determining how many rows of your item will fit on the screen. Call this rows.
3.while you still have items you need to layout:
1.Create a vertical LinearLayout, adding rows or less items to it.
2.Add your new vertical LinearLayout to the horizontal one.
There are some downsides versus what a "horizontal GridView" would get you:
1.All the views are loaded up immediately, which is bad for huge lists of items.
2.You need to know how big your items are, and they need to be the same size.
Upsides:
1.It's very easy to implement.
for more inf plz see this link
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
ScrollView scrollView = new ScrollView(this);//ScrollView
LinearLayout ll = new LinearLayout(this); //root LinearLayout
ll.setOrientation(LinearLayout.HORIZONTAL);//with horizontal orientation
LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.WRAP_CONTENT,1f);
LinearLayout l2 = new LinearLayout(this); //sub linearlayout
l2.setOrientation(LinearLayout.VERTICAL);//with vertical orientation
l2.setLayoutParams(layoutParams);
LinearLayout l3 = new LinearLayout(this); //sub linearlayout
l3.setOrientation(LinearLayout.VERTICAL);//with vertical orientation
l3.setLayoutParams(layoutParams);
int totalvalues=41; //i take count as 41
for(int i=0;i<totalvalues;i++){ // add the buttons in the layout based on condition
Button okButton=new Button(this);
okButton.setText("Button"+i);
if(i<=totalvalues/2){
l2.addView(okButton);
}
else{
l3.addView(okButton);
}
}
ll.addView(l2); //add sub linearlayout to root linearlayout
ll.addView(l3); //add sub linearlayout to root linearlayout
scrollView.addView(ll); //add the root linearlayout to scrollview
setContentView(scrollView);
}

Have you tried:
DisplayMetrics metrics = getResources().getDisplayMetrics();
float dpW = 0f;
int pixelsW = (int) (metrics.density * dpW + 0.5f);
TableLayout.LayoutParams lp = new TableLayout.LayoutParams(pixelsW, LayoutParams.WRAP_CONTENT, 1f);
TextView txt = new TextView(MainActivity.this);
ImageView img = new ImageView(MainActivity.this);
txt.setLayoutParams(lp);
img.setLayoutParams(lp);
Using TableLayout's LayoutParams, you can set the weight of the view, which, as you know, must be 1. We also use DisplayMetrics to convert a float into the "dp" format used in xml.
EDIT:
You can also set this LayoutParams to a LinearLayout.

Dynamically adding fragments with xml layout to GridLayout is not workng

In our app we are trying to dynamically add fragments to a GridLayout. The empty grid layout is defined in XML as is the layout for the fragment. At run time we examine some data and from that determine the number of fragments to add to the layout as well as which layout to use for each fragment. When we have the fragment assign a size to its generated view it all works, however if we specify the size in the layout file for the fragment nothing shows up in the grid layout. Obviously we could simply specify the size when we create the view but we would prefer to do it in the xml layouts for the fragments because that would allow us to take advantage of Android's built in system for selecting the correct layouts for each device.
I am using support library fragments. I am NOT using support library GridLayout if that makes a difference
The relevant code and xml follows:
The GridLayout XML:
<?xml version="1.0" encoding="utf-8"?>
<merge xmlns:android="http://schemas.android.com/apk/res/android">
<ScrollView
android:id="#+id/grid_scroll"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_above="#+id/bottom_fragment"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true"
android:layout_marginRight="8dp"
android:layout_marginTop="?android:attr/actionBarSize"
android:overScrollMode="ifContentScrolls" >
<GridLayout
android:id="#+id/grid"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:alignmentMode="alignMargins"
android:animateLayoutChanges="true"
android:columnCount="3"
android:columnOrderPreserved="true"
android:orientation="horizontal"
android:overScrollMode="ifContentScrolls"
android:rowOrderPreserved="true" >
</GridLayout>
</ScrollView>
</merge>
An Example of the Fragment XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="200dp"
android:layout_height="100dp"
android:alpha="1" >
<Button
android:id="#+id/button1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:alpha="1.0" />
</RelativeLayout>
The Fragment onCreateView() Method
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
super.onCreateView(inflater, container, savedInstanceState);
View view;
GridLayout.Spec rowSpec = GridLayout.spec(mRowStart, mRowSpan);
GridLayout.Spec columnSpec;
GridLayout.LayoutParams childParams;
if (large) {;
view = inflater.inflate(R.layout.my_place_large, container, false);
columnSpec = GridLayout.spec(mColumnStart, 2);
childParams = new GridLayout.LayoutParams(rowSpec, columnSpec);
//childParams.width = 200; //If I do this everything works regardless of the layout size
} else {
view = inflater.inflate(R.layout.my_place_small, container, false);
columnSpec = GridLayout.spec(mColumnStart, 1);
childParams = new GridLayout.LayoutParams(rowSpec, columnSpec);
//childParams.width = 100; //If I do this everything works regardless of the layout size
}
childParams.setMargins(0, 0, 0, 0);
//childParams.height = 100; //If I do this everything works regardless of the layout size
view.setLayoutParams(childParams);
view.setId(ID);
return view;
}
To Add Fragments to the Layout
private void populateGrid() {
RelativeLayout gridParent = (RelativeLayout) mParentActivity.findViewById(R.id.locations);
mLocationsGrid = (GridLayout) gridParent.findViewById(R.id.grid);
nColumns = mLocationsGrid.getColumnCount();
mAdapter = new MyAdapter(mContext, this, mResolver); //This is how I keep track of the various fragments depending on my app's state
int nCards = mAdapter.getNumberOfCards();
FragmentManager fragmentManager = mParentActivity.getSupportFragmentManager();
FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
for (int i = 0; i < nCards; ++i) {
fragmentTransaction.add(mLocationsGrid.getId(), mAdapter.getFragmentAtIndex(i), String.valueOf(i));
}
fragmentTransaction.commit();
mPopulated = true;
}
I think that should cover it. Just to reiterate, if I uncomment the lines which explicitly set the dimension in onCreateView(), they show up properly in GridLayout so I know everything that keeps track of the fragments and such works, as does the fragment transaction. The issue comes when I try and specify the size in the fragment's xml in which case I get a blank screen.
You thoughts, suggestions and musings are appreciated.
Thanks,
Jared

This is coming very late, but in the off chance this may still be of use. The problem is that you are overriding the XML layout parameters when you dynamically set the new LayoutParams. IE, when you do:
view.setLayoutParams(childParams);
This will erase the XMLs original height and width setting. Just because you are leaving the childParams width/height blank in code doesn't mean a value is not set. In a GridLayout's case, they are set to undefined.
The fix would be to first save the View's existing LayoutParam's height/width and use that when creating the new LayoutParam dynamically. Example:
if (large) {;
view = inflater.inflate(R.layout.my_place_large, container, false);
ViewGroup.LayoutParams oldParams = view.getLayoutParams();
columnSpec = GridLayout.spec(mColumnStart, 2);
childParams = new GridLayout.LayoutParams(rowSpec, columnSpec);
childParams.width = oldParams.width;
}
That will allow you to keep the width/height in XML while applying the row/col specs in code.