Develop Reference

Sort views in layout according to number of views

I am struggling at one thing. Let's say I have linear layout with set height and width is match_parent. I will have a set number of views 1 to 6 and I don't know at runtime how much I will receive from server. The problem is, how can I sort them in a layout so they scale their width accordingly to number of views present ? If there are more than 3 views I need to put them in two lines.
I was thinking about using layout weight, but can't think about solution that can put them to two lines. Any ideas ?

You have to dynamically add views to linear layout.
First create container layout in xml.
<LinearLayout
android:id="#+id/containerLayout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
/>
Then check,
if(list.size()<=3)
{
Then assign weight to container. i.e weight=list.size
for(int i=0;i<size;i++)
{
TextView textview = new TextView(this);
textview.setText(brandName);
textview.setWeight(1f);
container.addView(textview);
}
}
else
{
int totalRows= (list.size/3)+(list.size%3);
int count=0;
for(int i=0;i<totalRows;i++)
{
LinearLayout newLL = new LinearLayout(mContext);
newLL.setLayoutParams(new LinearLayout.LayoutParams(LinearLayout.LayoutParams.FILL_PARENT, LinearLayout.LayoutParams.WRAP_CONTENT));
newLL.setOrientation(LinearLayout.HORIZONTAL);
for(int j=count;j<count+3;j++)
{
count++;
TextView textview = new TextView(this);
textview.setText(brandName);
newLL.addView(textview);
}
container.addView(newLL);
}
}
You have to do something like this.This is not actual code.

You should use listview in your rooted LinearLayout and design single list item in an other xml layout , create a custom adapter for your single list item and set the adapter to your list view . this answer will help you how to create custome adapter

How to set position of view while using addView

I'm adding multiple Views by code into Layout. I need each new View to be above previous one(top of the parent layout).
EDIT: To be more accurate I'll describe what the app module should does. User start with clean screen and one button at the bottom of the screen. The button adds a View at the top of the screen. Next clicks should add next views above previous ones to make the newest View be on the top of a container. The app saves state and on restart user see views in the same order.

Call the following method from Button's onClick Event.
private final int LAYOUT_TOP_INDEX = 0;
private void addViewOnTop(View view){
if(layout != null && view !=null)
layout.addView(view, LAYOUT_TOP_INDEX);
}
where 'layout' is your Layout (e.g., LinearLayout) to which the View is to be added.

Would really need more information from you to give a more accurate answer, but if you're saying what i think you are then you can just add these views to a LinearLayout with orientation set to vertical.
And assuming you're iterating through a list to dynamically add views, instead of incrementing from 0, increment down from the size of the list.
for(int i = size; i >= 0; i--){
linearLayout.add(new TextView(Context));
}

View positions inside ViewGroups are defined by the LayoutParams
How does this happen? Views pass their LayoutParams to their parent ViewGroups
//100% programatic approach with simple LayoutParams
LinearLayout myLinearLayout = new LinearLayout(this);
//if the **parent** of the new linear layout is a FrameLayout
FrameLayout.LayoutParams layoutParams =
new FrameLayout.LayoutParams(
FrameLayout.LayoutParams.MATCH_PARENT, FrameLayout.LayoutParams.MATCH_PARENT);
//or if you have the XML file you don't have to worry about this
//myLinearLayout = (LinearLayout)findViewById(R.id.my_simple_linear_layout);
//you could have a LinkedList<TextView>
LinkedList<TextView> textViewList = new LinkedList<>();
//assuming the order is the correct order to be displayed
Iterator<TextView> descendingIterator = textViewList.descendingIterator();
while(descendingIterator.hasNext())
{
//just add each TextView programatically to the ViewGroup
TextView tView = descendingIterator.next();
myLinearLayout.addView(tView);
}
Just like we defined LayoutParams for the LinearLayout we could also define LayoutParams for the TextView
IMPORTANT: when setting LayoutParams you need to be sure they fit the VIEWGROUP, that is the parent of the View being added
private TextView textViewFactory(String myText) {
TextView tView = new TextView(getBaseContext());
//controling the position relatively to the PARENT
//because you are adding the textview to a LINEAR LAYOUT
LinearLayout.LayoutParams paramsExample =
new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT,
LinearLayout.LayoutParams.WRAP_CONTENT, 1.0f);
tView.setLayoutParams(paramsExample);
//configuring the insides of the textview
//you can also do all kinds of stuff programatically
tView.setGravity(Gravity.CENTER_HORIZONTAL);
tView.setPadding(10, 10, 10, 10);
tView.setTypeface(Typeface.DEFAULT_BOLD);// (null, Typeface.BOLD_ITALIC);
tView.setTypeface(Typeface.SANS_SERIF);
tView.setTypeface(null, Typeface.ITALIC);
tView.setTypeface(Typeface.defaultFromStyle(R.style.AppTheme));
tView.setId(R.id.aux_info);
tView.setText(myText);
//.........all kinds of stuff really
return tView;
}

If you mean adding a view programmatically so that the new one is added above the previous one, instead of below it, then I suggest this:
Maintain an ArrayList with the items you want to turn into views
Put them into a ListView
When you want to add a new view that must appear at the top of the list, insert it as the first element of your ArrayList and recreate the ListView from it.

Android - changing margin issue?

I have one main linear layout which contains dynamically generated linear layouts. I am animating these layouts on ACTION_DOWN. But if i try to change the margin (top or bottom) of one layout, it affects other layouts as well. How to change one layouts margin without affecting others.
Any help would be rally appreciated.
Thanks.
EDIT
public View getLinearView() {
ChildLinearLayout linearLayout = new ChildLinearLayout(context);
LayoutParams layoutParams = new LayoutParams(500, 500);
linearLayout.setLayoutParams(layoutParams);
linearLayout.setBackgroundColor(Color.RED);
layoutParams.setMargins(20, 20, 20, 20);
layoutParams.gravity = Gravity.CENTER_HORIZONTAL;
TextView textView = new TextView(context);
textView.setText("Hello World");
linearLayout.addView(textView);
System.out.println("View Added");
views.add(linearLayout);
return linearLayout;
}

I think since you are calling
layoutParams.setMargins(20, 20, 20, 20)
for every dynamically generated layout, if you change these values then it will affect every one of your dynamically generated layouts.
Instead you could change your
getLinearView() method to getLinearView(int margin_value)
and every time you call this method for your dynamically generated layout, you could pass in the value you want for that particular layout.
ex:
If I have 5 layouts and I want to set margin of first one to 50 and others to 20 then
for(int i=0;i<5;i++)
{
if(i==0)
view=getLinearView(50);
else
view=getLinearView(20);
}

How to create Scrollview programmatically?

I have one table "TABLE_SUBJECT" which contain a number of subjects. I need to create
one horizontal scroll view with Subject.
How do I create a ScrollView with database items programmatically? If I enter 1o subject then it will be appear in scroll view as a button. Is it possible?

you may create it as below:
ScrollView scroll = new ScrollView(context);
scroll.setBackgroundColor(android.R.color.transparent);
scroll.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
scroll.addView(yourTableView);

if you have many elements first you need to wrap-up and add in the Scroll view; for example i need a many text view inside of scrollview, so you need to create ScrollView->LinearLayout->Many textview
ScrollView scrollView = new ScrollView(context);
scrollView.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT));
TextView textView = new TextView(context);
textView.setText("my text");
LinearLayout linearLayout = new LinearLayout(context);
linearLayout.setOrientation(LinearLayout.VERTICAL);
linearLayout.setGravity(Gravity.RIGHT);
linearLayout.addView(textView);
scrollView.addView(linearLayout);

this may help you.
HorizontalScrollView hsrll = (HorizontalScrollView)findViewById(R.id.hrsll);
b = new Button(this);
for (int i = 0; i < 5; i++) {
b.setWidth(LayoutParams.WRAP_CONTENT);
b.setHeight(LayoutParams.WRAP_CONTENT);
b.setText("b"+i);
b.setId(100+i);
hsrll.addView(b);
}
instead of for loop just modify the code as your need(no of records in db). but this the code for creating buttons in dynamically.

I was doing it like this:
Create xml with LinearLayout inside the ScrollView
Create xml as item in ScrollView
In activity set main content as xml with ScrollView
Loop through all table elements with adding new View to LinearLayout form main view
For me works fine.

In Kotlin you can use the below code
val scroll = ScrollView(context)
scroll.setBackgroundColor(R.color.transparent)
scroll.layoutParams = LayoutParams(
LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT
)
scroll.addView(yourTableView)

Problems vertically aligning a Button and horizontally oriented LinearLayout within a vertcally oriented LinearLayout

Im posting from my phone so please excuse stupid typos and formatting issues.
I have an activity which lists saved games that the player can load.
I created a simple layout xml file which defines a ScrollView. On load, I grab all the saved games and programatically add a view for each saved game to a vertically oriented LinearLayout child of the ScrollView.
The view for each game consists of a Horizontally oriented LinearLayout which in turn contains a Button and a vertically oriented LinearLayout. That LinearLayout in turn contains some TextViews and ImageViews (and one more LinearLayout which I'm ommitting here for the sake of clarity).
The hierarchy looks something like this (some details omitted).
ScrollView
LinearLayout - vertical
Each saved game:
LinearLayout - horizontal
Button - load game
LinearLayout - vertical
TextView - game name
TextView - date string
My problem:
I would like the top of the button and the "game name" texview to be vertically aligned but the TextView (or maybe it's LinearLayout parent) has some rogue padding on top that I can't get rid of. See screenshot for details.
LoadSaved class:
Note: mScrollView is badly named. It refers to the ScrollView's child LinearLayout.
public class LoadSaved extends Activity {
public LinearLayout mScrollView;
private MinerDb mDb;
public void onCreate(Bundle b) {
super.onCreate(b);
setContentView(R.layout.loadsaved);
mDb = new MinerDb(this);
mScrollView = (LinearLayout) findViewById(R.id.load_scroll_view);
Bundle[] savedGames = mDb.getSavedGames();
for (int i = 0; i < savedGames.length; i++) {
Bundle game = savedGames[i];
final int gameId = game.getInt("gameId");
String name = game.getString("name");
String date = game.getString("date");
Bundle player = game.getBundle("player");
int playerMoney = player.getInt("money");
int playerHealth = player.getInt("health");
LinearLayout gameContainer = new LinearLayout(getApplicationContext());
gameContainer.setPadding(5, 5, 5, 5);
gameContainer.setGravity(Gravity.TOP);
gameContainer.setOrientation(LinearLayout.HORIZONTAL);
gameContainer.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
Button loadButton = new Button(getApplicationContext());
loadButton.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
loadButton.setText("Load");
LinearLayout gameInfo = new LinearLayout(getApplicationContext());
gameInfo.setOrientation(LinearLayout.VERTICAL);
gameInfo.setPadding(10,0,10,10);
gameInfo.setGravity(Gravity.TOP);
gameInfo.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
TextView nameView = new TextView(getApplicationContext());
nameView.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
nameView.setGravity(Gravity.TOP);
nameView.setText(name);
TextView dateView = new TextView(getApplicationContext());
dateView.setPadding(5,0,0,0);
dateView.setGravity(Gravity.TOP);
dateView.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
dateView.setText(date);
LinearLayout playerView = new LinearLayout(getApplicationContext());
playerView.setOrientation(LinearLayout.HORIZONTAL);
playerView.setPadding(5,0,0,0);
playerView.setGravity(Gravity.TOP);
playerView.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT));
TextView playerMoneyView = new TextView(getApplicationContext());
playerMoneyView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
playerMoneyView.setPadding(0,0,10,0);
playerMoneyView.setTextColor(Color.GREEN);
playerMoneyView.setText("$" + playerMoney);
TextView playerHealthView = new TextView(getApplicationContext());
playerHealthView.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
playerHealthView.setPadding(0,0,10,0);
playerHealthView.setTextColor(Color.RED);
playerHealthView.setText(playerHealth + "%");
playerView.addView(playerMoneyView);
playerView.addView(playerHealthView);
gameInfo.addView(nameView);
gameInfo.addView(dateView);
gameInfo.addView(playerView);
gameContainer.addView(loadButton);
gameContainer.addView(gameInfo);
mScrollView.addView(gameContainer);
loadButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
Log.e("LoadSaved", "LoadSaved::onCreate: Clicking: " + gameId);
Intent loadGameIntent = new Intent(LoadSaved.this, Miner.class);
loadGameIntent.putExtra("load_game", gameId);
startActivity(loadGameIntent);
finish();
}
});
}
}
}
loadsaved.xml
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:id="#+id/load_scroll_view" />
</ScrollView>
</LinearLayout>

If you want any kind of alignment, why don't you use a RelativeLayout? That's basically designed to align one view with another. android:layout_alignTop sounds like something you want.
(And, of course, verify that the padding values are the same in all controls, but I'm sure you did that.)

Why don't you try using a ListView for that kind of gui.
You will still need to define a row xml.

+1 to the answers suggesting ListView and RelativeLayout. For this type of situation you probably want a ListView with an item layout using RelativeLayout. (ListView will scale much better if there are many items, and if this is for a list of saved games it seems like this could grow quite a bit.) For this type of UI it's recommended to have the whole row/list item clickable rather than use a small Load button, but that's a design issue and ultimately up to you.
Don't use getApplicationContext for creating your views. Activity is a Context, just pass this in your case.
By default LinearLayouts try to align child views by their text baseline if present. Note that the bottom of your button's Load text aligns perfectly with the CURRENT_GAME text in your screenshot. Try gameContainer.setBaselineAligned(false).
Normally your gameInfo layout would only report the baseline of one of its children if you set a baselineAlignedChildIndex, but it looks like this behavior changed between cupcake and eclair when creating LinearLayouts programmatically. (Link to the commit that changed it in AOSP here.)