Button

The Android Button component is a View subclass which is capable of showing button. Being a subclass of View the Button component can be used in your Android app’s GUI inside a ViewGroup, or as the content view of an activity.

For button we can use all the properties which we applied for Textview. The above properties we mentioned in XML file like below code.

<Button
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:text="@string/bt"
    android:textSize="20sp"
    android:textColor="#234098"
    android:textAllCaps="true"
    android:textStyle="bold|italic"
    android:id="@+id/bt"
    android:typeface="monospace"
    android:gravity="center"/>

For the above textview am assigning text dynamically from java with below code

Button button;
button= (Button) findViewById(R.id.bt);
Click Listener for Button
button.setOnClickListener(new View.OnClickListener() {
    @Override
    public void onClick(View v) {        
    }
});

Example Program for Dynamic text

Activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
      android:orientation="vertical"
    tools:context="androiindians.androindian.MainActivity">

    <TextView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/tv"
        android:textSize="20sp"
        android:textColor="#234098"
        android:textAllCaps="true"
        android:textStyle="bold|italic"
        android:id="@+id/tv"
        android:typeface="monospace"
        android:gravity="center"/>
    <Button
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="@string/bt"
        android:textSize="20sp"
        android:textColor="#234098"
        android:textAllCaps="true"
        android:textStyle="bold|italic"
        android:id="@+id/bt"
        android:typeface="monospace"
        android:gravity="center"/>
</LinearLayout>

Striing.xml

<resources>
    <string name="app_name">Androindian</string>
    <string name="tv">Hello Androindian</string>
    <string name="bt">Click me</string>
</resources>

MainActivity.java

package androiindians.androindian;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
    TextView textView;
    Button button;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textView= (TextView) findViewById(R.id.tv);
        button= (Button) findViewById(R.id.bt);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                textView.setText("Hi Hello Good morning");
            }
        });
    }
}