Change Font size programmatically in Android

Question

Hi I'm a newbie in android. I just wanted to know if there is any way to change the font size of a String in android?

String name = db.getName(Id)
String str = "Name : " + name;

I want to have "Name" with bigger font size than the value in "name".Where "name" is the value I get from the database.

Please do suggest any method to do this!! Thanks in advance!!

Answer 1

Use

TextView textView = (TextView) findViewById(R.id.textView);
Spannable span = new SpannableString(str);
span.setSpan(new RelativeSizeSpan(0.8f), start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
textView.setText(span);

on a TextView to get different TextSizes.

Answer 2

When you are putting the text into a textView you can increase the font. For example

textView.setText(yourString);
textView.setTextSize(20);

Or you can give the font size in the Layout.xml file itself

<TextView
      android:id = "@+id/textView"
       ........
       android:textSize = "20dp"/>

Please feel free to ask any further doubts if you need further clarifications.

Answer 3

You do not change the font size of a String instead you change the font size of the text when you display the String (for instance in the TextView if you are using one). A String is simply a data object holding the text you want to display and has nothing to do with the way you display it .

Answer 4

You need to use a Spannable and give it to your TextView in order to modify just a portion of the text. To change the size use :

 span.setSpan(new RelativeSizeSpan(0.8f), start, end, Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);

Answer 5

You can't change the font size of a String , because String is just a set of characters, but you can alter the font size of a TextView that contains this String using the setTextSize() method. Hope this helps.

Answer 6

You can't. As you can't in any other language. What you need to do is to change the fontsize of the element that will display the text, not the String itself.

Try creating a layout in res/layout/ folder, add a TextView element and then search for the textSize property.

Answer 7

The best Idea to show variances in a ListView is showing headers. A Simple Example is explained here It states the following code:

Simple activity Xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">

    <ListView
        android:id="@+id/add_journalentry_menuitem"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />
    <ListView
        android:id="@+id/list_journal"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content" />
</LinearLayout>

List Header

<TextView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/list_header_title"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:paddingTop="2dip"
    android:paddingBottom="2dip"
    android:paddingLeft="5dip"
    style="?android:attr/listSeparatorTextViewStyle" />

List Item

<?xml version="1.0" encoding="utf-8"?>
<!-- list_item.xml -->
<TextView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/list_item_title"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:paddingTop="10dip"
    android:paddingBottom="10dip"
    android:paddingLeft="15dip"
    android:textAppearance="?android:attr/textAppearanceLarge"
    />

Main Activity

import java.util.HashMap;
import java.util.Map;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
import android.widget.AdapterView.OnItemClickListener;

public class ListSample extends Activity
    {

        public final static String ITEM_TITLE = "title";
        public final static String ITEM_CAPTION = "caption";

        // SectionHeaders
        private final static String[] days = new String[]{"Mon", "Tue", "Wed", "Thur", "Fri"};

        // Section Contents
        private final static String[] notes = new String[]{"Ate Breakfast", "Ran a Marathan ...yah really", "Slept all day"};

        // MENU - ListView
        private ListView addJournalEntryItem;

        // Adapter for ListView Contents
        private SeparatedListAdapter adapter;

        // ListView Contents
        private ListView journalListView;

        public Map<String, ?> createItem(String title, String caption)
            {
                Map<String, String> item = new HashMap<String, String>();
                item.put(ITEM_TITLE, title);
                item.put(ITEM_CAPTION, caption);
                return item;
            }

        @Override
        public void onCreate(Bundle icicle)
            {
                super.onCreate(icicle);

                // Sets the View Layer
                setContentView(R.layout.main);

                // Interactive Tools
                final ArrayAdapter<String> journalEntryAdapter = new ArrayAdapter<String>(this, R.layout.add_journalentry_menuitem, new String[]{"Add Journal Entry"});

                // AddJournalEntryItem
                addJournalEntryItem = (ListView) this.findViewById(R.id.add_journalentry_menuitem);
                addJournalEntryItem.setAdapter(journalEntryAdapter);
                addJournalEntryItem.setOnItemClickListener(new OnItemClickListener()
                    {
                        @Override
                        public void onItemClick(AdapterView<?> parent, View view, int position, long duration)
                            {
                                String item = journalEntryAdapter.getItem(position);
                                Toast.makeText(getApplicationContext(), item, Toast.LENGTH_SHORT).show();
                            }
                    });

                // Create the ListView Adapter
                adapter = new SeparatedListAdapter(this);
                ArrayAdapter<String> listadapter = new ArrayAdapter<String>(this, R.layout.list_item, notes);

                // Add Sections
                for (int i = 0; i < days.length; i++)
                    {
                        adapter.addSection(days[i], listadapter);
                    }

                // Get a reference to the ListView holder
                journalListView = (ListView) this.findViewById(R.id.list_journal);

                // Set the adapter on the ListView holder
                journalListView.setAdapter(adapter);

                // Listen for Click events
                journalListView.setOnItemClickListener(new OnItemClickListener()
                    {
                        @Override
                        public void onItemClick(AdapterView<?> parent, View view, int position, long duration)
                            {
                                String item = (String) adapter.getItem(position);
                                Toast.makeText(getApplicationContext(), item, Toast.LENGTH_SHORT).show();
                            }
                    });
            }

    }

Two more additional XMLs are present there, but with these given structure you can Implement what you want in a better way rather than Just size difference.

PS- the full app is available here

Answer 8

Spannable font: In order to set a different font size to some portion of text, a RelativeSizeSpan can be used, as shown in the following example:

Spannable spannable = new SpannableString(firstWord+lastWord); 
spannable.setSpan(new ForegroundColorSpan(firstWordColor), 0, firstWord.length(),Spannable.SPAN_EXCLUSIVE_EXCLUSIVE);
spannable.setSpan(new ForegroundColorSpan(lastWordColor), firstWord.length(), firstWord.length()+lastWord.length(), Spannable.SPAN_EXCLUSIVE_EXCLUSIVE); 
textview.setText( spannable );

Credit: Copy and Pasted from this webpage .

Answer 9

You cannot do that. You can add the string to the View lets say EditText or TextView and set the text Size for the view in xml as below:

android:textSize="18dp"

or programatically, you can do like this:

<YourTextView>.setTextSize(18);

Due to lack of idea before, i had asked similar question here . I hope you will get an idea with this link.