Develop Reference

How to center a textView with java code inside a linear layout

So I want to center a text View inside a linear layout where I have 2 other objects that populate the linear layout. I have a imageView and another textView. How would I go about centering the textView so the text is in the middle of the screen? This is what I have so far.
View linearLayout = findViewById(R.id.rockLayout);
ImageView mineralPicture = new ImageView(this);
TextView mineralName = new TextView(this);
TextView mineralProperties = new TextView(this);
mineralProperties.setText("The properties are: " + Statics.rockTable.get(rockName).getDistinctProp());
mineralProperties.setId(2);
mineralName.setText("This mineral is: " + rockName);
mineralName.setGravity(Gravity.CENTER);
mineralName.setId(1);
mineralName.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
mineralProperties.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT,LayoutParams.WRAP_CONTENT));
mineralPicture.setId(3);
mineralPicture.setImageResource(R.drawable.rocks);
mineralPicture.setAdjustViewBounds(true);
mineralPicture.setMaxHeight(100);
mineralPicture.setMaxWidth(200);
mineralPicture.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
((LinearLayout)linearLayout).addView(mineralName);
((LinearLayout)linearLayout).addView(mineralProperties);
((LinearLayout)linearLayout).addView(mineralPicture);
I should mention I've tried doing such things as mineralName.setGravtiy(Gravity.CENTER); and it hasn't worked.

a) let the textview match_parent on the width and use gravity center
b) on the textview layout params set the layout_gravity to center (sorry for the terms I normally do this in XML)!

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)

handling LinearLayout within a ScrollView

Originally, I had LinearLayout>ScrollView>TableLayout and the code below:
LinearLayout layout = (LinearLayout) View.inflate(this, R.layout.photos_layout, null);
setContentView(layout);
// TODO Auto-generated method stub
//get the tableLayout which we created in main.xml
tl = (TableLayout)findViewById(R.id.tableLayout1);
for(int i = 0; i < names.length; i++) {
//Create a new row to be added.
TableRow tr = new TableRow(this);
//Create text views to be added to the row.
TextView tv1 = new TextView(this);
TextView tv2 = new TextView(this);
//Put the data into the text view by passing it to a user defined function createView()
createView(tr, tv1, Integer.toString(i+1));
createView(tr, tv2, names[i]);
//Add the new row to our tableLayout tl
tl.addView(tr);
}
The problem is that a scrollView can only have one child, so if I wanted to add more views in addition to the tableLayout I can't. In order to overcome this problem I made the hierarchy like LinearLayout>ScrollView>linearLayout>tableLayout. However, now the code above crashes the app.
What do I need to change in order to populate my table, as well as add views to my newly created linearlayout?

I'd suggest removing the parent LinearLayout. Scrollview in itself can be the parent, and then have one LinearLayout as its only direct child.
In the code you posted that you mentioned was crashing, you're not adding any view to your "newly-created" LinearLayout, instead you're adding a new row to your TableLayout, which if I guess correctly, is inside your scrollview. This is perfectly ok and should not be the cause of the crash.

Android TextView and text wrapping

I have a TextView inside a TableRow. The text contained in this TextView is tipically larger than the screen. As such, I would like for the the text to wrap into multiple lines.
TableLayout table = (TableLayout)findViewById(R.id.myTable);
TableRow row = new Tablerow(context);
TextView view = new TextView(context);
view.setText(stringWithLotsOfCharacters);
view.setSingleLine(false);
row.add(view);
table.addview(row, new TableLayout.LayoutParams(LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT);
I tried using "setSingleLine" but it does not have the effect I was looking for.
Any suggestions? Thanks.

Add android:shrinkColumns="1" for the column you want to wrap to the TableLayout in your layout or android:shrinkColumns="*" if you want to wrap all columns.
You can also do it programmatically with setColumnShrinkable:
public void setColumnShrinkable (int columnIndex, boolean isShrinkable)

view.setHeight(LayoutParams.WRAP_CONTENT);

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.)