Develop Reference

How can i center textviews in a table row that is constantly being generated dynamically?

I have a zone list. And my function creates a table row for each zone and adds a textview of zone's name to this row and then adds this row to my TableLayout. Since the zonelist is populated from a database, the list may change during the lifetime of app.
What I'm trying to do is to center each textview in each row horizontally. I'm checking every source and people keep saying "add this piece of code to your XML file...". Since I'm creating these rows and textviews dynamically, I don't have any objects to manipulate in my XML file. So I have to somehow manage it by coding in Java side. Any help would be appriciated.
private void addTextView(final Zone zone) {
TableRow row = new TableRow(DashboardFragment.this.getActivity());
TextView textView = new TextView(DashboardFragment.this.getActivity());
textView.setId(zone.getId());
textView.setText(zone.getName());
textView.setTextColor(Color.BLACK);
textView.setTextSize(25);
TextView seperator = new TextView(DashboardFragment.this.getActivity());
seperator.setText("_____________________________________________________________________________________________________________________________");
seperator.setTextSize(25);
seperator.setTextColor(Color.BLACK);
TableRow seperate = new TableRow(DashboardFragment.this.getActivity());
seperate.addView(seperator);
textView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(getActivity().getApplication(), ZoneContentsActivity.class);
intent.putExtra("zone",zone);
startActivity(intent);
}
});
row.addView(textView);
layout.addView(row);
layout.addView(seperate);
}
(Note: I know the way I seperate is not the best xD. So any help on this side would be appriciated as well.)

Try this:
In layout folder, (layout_row.xml)
<?xml version="1.0" encoding="utf-8"?>
<TableRow xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="wrap_content">
<LinearLayout android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_weight="1"
android:orientation="vertical">
<TextView
android:id="#+id/nameTxt"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="TextView"
android:gravity="center" />
<include layout="#layout/line_horizontal_gray" />
</LinearLayout>
</TableRow>
And for adding Row to table layout:
private void addRow(final Zone zone){
LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
TableRow rowView = (TableRow)inflater.inflate(R.layout.layout_row, null);
TextView textView = rowView.findViewById(R.id.nameTxt);
textView.setText(zone.getName());
textView.setTextColor(Color.BLACK);
textView.setTextSize(25);
layout.addView(rowView);
}
Seperator is added on the layout_row. Hope it might help.
line_horizontal_gray.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="1dp"
android:background="#android:color/darker_gray">
</LinearLayout>

You can try
textView.setGravity(Gravity.CENTER_HORIZONTAL);

How to Create a Checkbox Automatically on user input

In My Activity i have a Edit Text and Button When the user enter the button " Add " the checklist want to create Automatically with the name of the user entered in the edit text
how to create a checkbox in java program based on the user input
when i click the Add Button the list was not updated ( the userinput was not converted into checkbox and it doesnot display the name in bottom )
Here is My XML Code
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Enter Name to Add in the list"
android:id="#+id/ed_name"
android:layout_marginTop="15dp"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add"
android:id="#+id/btn_add"
android:layout_below="#+id/ed_name"
android:layout_centerHorizontal="true"
android:layout_marginTop="15dp"
/>
</RelativeLayout>
here is My java code
public class MainActivity extends AppCompatActivity {
EditText uinput;
Button btnadd;
CheckBox cbname;
ScrollView sv;
RelativeLayout ll;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
sv = new ScrollView(this);
ll = new RelativeLayout(this);
// ll.setOrientation(LinearLayout.VERTICAL);
sv.addView(ll);
uinput = findViewById(R.id.ed_name);
btnadd = findViewById(R.id.btn_add);
btnadd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String Name = uinput.getText().toString();
CheckBox cb = new CheckBox(getApplicationContext());
cb.setText(Name);
ll.addView(cb);
}
});
}

I suggest you to add everything that is static in the activity_main.xml layout file as :
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity2">
<EditText
android:id="#+id/ed_name"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:ems="10"
android:hint="Enter name to add in the list"
android:inputType="textPersonName"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<Button
android:id="#+id/btn_add"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:text="Add"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/ed_name" />
<ScrollView
android:id="#+id/scrollview"
android:layout_width="409dp"
android:layout_height="612dp"
android:layout_marginTop="8dp"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/btn_add">
<LinearLayout
android:id="#+id/linear_layout"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical" />
</ScrollView>
</androidx.constraintlayout.widget.ConstraintLayout>
Now, Checkbox are the one which we will generate programmatically and add them to the LinearLayout which is the only child of ScrollView(it supports single child only). A sample code for MainActivity doing that is here :
public class MainActivity extends AppCompatActivity {
// declare the required views variable
private EditText uInput;
private LinearLayout linearLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main2);
// initializes required view variable
uInput = findViewById(R.id.ed_name);
linearLayout = findViewById(R.id.linear_layout);
Button btnAdd = findViewById(R.id.btn_add);
btnAdd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String name = uInput.getText().toString();
if (!name.isEmpty()) {
CheckBox checkBox = new CheckBox(MainActivity.this);
checkBox.setText(name);
linearLayout.addView(checkBox);
} else
Toast.makeText(MainActivity.this, "The name cannot be empty!", Toast.LENGTH_LONG).show();
}
});
}
}
It also checks whether or not the text in EditText is empty and if it is generates a suitable Toast message to not permit the user create a empty Checkbox. Hope, this helps!

You didn't add the ScrollView to your layout, So the R.layout.activity_main know nothing about your added views.
So, inflate your root ViewGroup of your layout, add the ScrollView to it and set constraints/attributes according to the type of your root ViewGroup.
Add an id to the root layout
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/root"
tools:context=".MainActivity">
Replace the ScrollView inner RelativeLayout with a LinearLayout and add the ScrollView with an attribute param RelativeLayout.BELOW to be at the bottom of the btn_add
ScrollView sv = new ScrollView(this);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
// ll.setOrientation(LinearLayout.VERTICAL);
sv.addView(ll);
EditText uinput = findViewById(R.id.ed_name);
Button btnadd = findViewById(R.id.btn_add);
RelativeLayout rootLayout = findViewById(R.id.root);
// Set constraints/attributes to the sv
RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.MATCH_PARENT, RelativeLayout.LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.BELOW, btnadd.getId());
rootLayout.addView(sv, params);
btnadd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
String Name = uinput.getText().toString();
CheckBox cb = new CheckBox(getApplicationContext());
cb.setText(Name);
ll.addView(cb);
}
});

This code will add a checkbox in your view
since you don't have any provided code, ill give you an idea to come up on your own strategies or style
ScrollView sv = new ScrollView(this);
LinearLayout ll = new LinearLayout(this);
ll.setOrientation(LinearLayout.VERTICAL);
sv.addView(ll);
Button b = new Button(this);
b.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
CheckBox cb = new CheckBox(getApplicationContext());
cb.setText(myTextBoxText.getText());
ll.addView(cb);
}
});

How to create LinearLayout with ImageView and add it to another LinearLayout programatically

I'm having troubles trying to create a LinearLayout with an ImageView inside programatically (and add this LinearLayout to another LinearLayout). The XML code that I'm tryng to recreate is this:
<LinearLayout
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/linearLayout_morty_combinationsV"
android:gravity="center">
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center"
android:background="#color/black"
android:layout_weight="1">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/morty"
android:id="#+id/imageView1"/>
</LinearLayout>
<LinearLayout
android:orientation="vertical"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:gravity="center"
android:background="#color/black"
android:layout_weight="1">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="#drawable/morty"
android:id="#+id/imageView2"/>
</LinearLayout>
</LinearLayout>
This is my java code
LinearLayout ll_combinations = (LinearLayout) findViewById(R.id.linearLayout_morty_combinationsV);
Iterator<MortyObj> iterator = mortys.iterator();
while (iterator.hasNext()) {
final MortyObj mortyC = iterator.next();
LinearLayout ll_new = new LinearLayout(this);
ll_new.setOrientation(LinearLayout.VERTICAL);
ll_new.setGravity(Gravity.CENTER);
LinearLayout.LayoutParams params = new LinearLayout.LayoutParams(LinearLayout.LayoutParams.WRAP_CONTENT, LinearLayout.LayoutParams.MATCH_PARENT);
params.weight = 1f;
ll_new.setLayoutParams(params);
ll_new.setBackgroundColor(Color.WHITE);
ImageView morty_imageview = new ImageView(this);
try {
InputStream ims = getAssets().open("morty_images/" + mortyC.getId() + ".png");
Drawable d = Drawable.createFromStream(ims, null);
morty_imageview.setImageDrawable(d);
} catch (IOException e) {
e.printStackTrace();
}
FrameLayout.LayoutParams imgParams = new FrameLayout.LayoutParams(FrameLayout.LayoutParams.WRAP_CONTENT, FrameLayout.LayoutParams.WRAP_CONTENT);
morty_imageview.setLayoutParams(imgParams);
ll_new.addView(morty_imageview);
ll_combinations.addView(ll_new);
}
This is how it should look:
XML
And this is how It looks:
JAVA
I've been stuck in this for the last 2 hours.

You can create a layout with something like
View view = (View) findViewById(R.layout.current_layout); //the layout you set in `setContentView()`
LinearLayout picLL = new LinearLayout(CurrentActivity.this);
picLL.layout(0, 0, 100, 0);
picLL.setLayoutParams(new LayoutParams(1000, 60));
picLL.setOrientation(LinearLayout.HORIZONTAL);
((ViewGroup) view).addView(picLL);
What parameters you pass in layout() are obviously going to depend on what you want. Then you can create separate Views to add to the Layout you just created. But I highly advise reading through the docs to understand what all can be done here.
Edit
ImageView myImage = new ImageView(this);
picLL.addView(myImage);
//set attributes for myImage;

Just found the problem. If i load an image from res/drawables I get the view I want, if I load it from assets it doesn't work

Create Horizontal and Vertical Scroll View Dynamically Android

In my project i managed to display the database in the form of rows and columns of edit Texts and text Views.But the as the number of rows and columns increase it is not possible to view the added data , they dont fit into the screen.
so i think i needed a horizontal scrollview and a vertical scrollview for viewing entire rows and columns. Below
is my code kindly help me how to achieve this.
Please do help me thanks in advance
xml code is
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<TableLayout
android:layout_width="wrap_content"
android:stretchColumns="0,1,2,3,4,5"
android:id="#+id/maintable"
android:layout_height="wrap_content"
android:layout_weight="1.0">
</TableLayout>
</LinearLayout>
The following is the code for page where i wanna display my rows and columns
public class ViewActivity extends Activity {
EditText col1;
EditText col2;
TextView Id;
EditText col4;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_view);
ScrollView sv = new ScrollView(this);
HorizontalScrollView hs =new HorizontalScrollView(this);
TableLayout tl = (TableLayout) findViewById(R.id.maintable);
//CREATING A LIST OF HEADINGS
TableRow tr1 = new TableRow(this);
tr1.setLayoutParams(new LayoutParams( LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT ));
Id = new TextView(this);
Id.setText("COL1");
tr1.addView(Id);
Id = new TextView(this);
Id.setText("COL2");
tr1.addView(Id);
Id = new TextView(this);
Id.setText("COL3");
tr1.addView(Id);
Id = new TextView(this);
Id.setText("Rssi");
tr1.addView(COL4);
Id = new TextView(this);
Id.setText("Delete");
tr1.addView(COL5);
Id = new TextView(this);
Id.setText("Update");
tr1.addView(COL6);
hs.setLayoutParams(new LayoutParams(LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
tl.addView(tr1,new TableLayout.LayoutParams(
LayoutParams.FILL_PARENT,
LayoutParams.WRAP_CONTENT));
// CREATING ROWS AND COLUMNS DYNAMICALLY
final DBclass entry = new DBclass(ViewActivity.this);
entry.open();
Cursor c = entry.getAllRecords();
int count =0;
if(c.moveToFirst()){
do{
TableRow tr = new TableRow(this);
tr.setId(count);
tr.setLayoutParams(new LayoutParams( LayoutParams.FILL_PARENT, LayoutParams.WRAP_CONTENT ));
/* CODE FOR
COLUMNS DISPLAYED IN THE FORM OF
EDITTEXTS AND TEXTVIEWS
*/
tl.addView(tr, new TableLayout.LayoutParams(
LayoutParams.FILL_PARENT,
LayoutParams.FILL_PARENT));
count++;
}while(c.moveToNext());
}
}

I'm fairly sure you could simply put your TableLayout inside a ScrollView to solve this problem. No need to fiddle with adding Views programatically, just predefine it in the XML layout resource. Like this:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical">
<ScrollView
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TableLayout
android:layout_width="wrap_content"
android:stretchColumns="0,1,2,3,4,5"
android:id="#+id/maintable"
android:layout_height="wrap_content"
android:layout_weight="1.0">
</TableLayout>
</ScrollView>
</LinearLayout>
Keep in mind ScrollView is vertical, so you'd need to add a HorizontalScrollView in there to add horizontal scrolling as well.

Dynamically added table rows not appearing

I have seen many posts regarding dynamically adding table rows, but I am not sure what I'm missing.
When I execute the following, nothing is displayed (aside from application title bar).
My Layout:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:id="#+id/table_view_test_main"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android"
>
<ScrollView
android:id="#+id/tvt_scroll"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
>
<RelativeLayout
android:id="#+id/tvt_scroll_relative"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<TableLayout
android:id="#+id/tvt_tableview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
>
</TableLayout>
</RelativeLayout>
</ScrollView>
</RelativeLayout>
My Activity:
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.table_view);
TableLayout tableLayout = (TableLayout) findViewById(R.id.tvt_tableview);
TableRow tableRow = new TableRow(this);
tableRow.setLayoutParams(new TableRow.LayoutParams(TableRow.LayoutParams.FILL_PARENT, TableRow.LayoutParams.WRAP_CONTENT));
TextView column1 = new TextView(this);
column1.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
column1.setBackgroundColor(Color.YELLOW);
column1.setTextColor(Color.BLUE);
column1.setText("Col1 Value");
tableRow.addView(column1);
TextView column2 = new TextView(this);
column2.setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.FILL_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
column2.setBackgroundColor(Color.RED);
column2.setTextColor(Color.GREEN);
column2.setText("Col2 Value");
tableRow.addView(column2);
tableLayout.addView(tableRow, new TableLayout.LayoutParams(TableLayout.LayoutParams.FILL_PARENT, TableLayout.LayoutParams.WRAP_CONTENT));
//tl.refreshDrawableState();
//findViewById(R.id.tvt_scroll_relative).refreshDrawableState();
}

Change the two references
ViewGroup.LayoutParams
to
TableRow.LayoutParams
and it should work.
Adding layout params to a widget requires that the LayoutParams are a inner class of the surrounding layout container.

I think this has something to do with you setting the layout params to the TextViews. If you remove those definitions the info appears. Also if you take a look at the official documentation for TableRow you can see:
The children of a TableRow do not need to specify the layout_width and layout_height attributes in the XML file. TableRow always enforces those values to be respectively MATCH_PARENT and WRAP_CONTENT.