Q:

how to define a reset button to clear all text field at one click?

<ScrollView
    android:id="@+id/ScrollView1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fillViewport="true" >

     <LinearLayout
         android:id="@+id/MainParent"
         android:layout_width="wrap_content"
         android:layout_height="match_parent" >

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        android:layout_marginLeft="20sp"
        android:layout_marginRight="20sp"
        android:orientation="vertical" >

        <TextView
            android:id="@+id/textView1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="80sp"
            android:text="Sim Card Master"
            android:textAppearance="?android:attr/textAppearanceSmall"
            android:textColor="@color/pumpkinorange"
            android:textSize="17sp" />

        <TextView
            android:id="@+id/simno"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="5sp"
            android:text="Sim No"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/darkblue"
            android:textSize="14sp" />

        <EditText
            android:id="@+id/simName"
            android:layout_width="275dp"
            android:layout_height="wrap_content"
            android:selectAllOnFocus="true" >
            <requestFocus />
        </EditText>

        <TextView
            android:id="@+id/TextView01"
            android:layout_width="145dp"
            android:layout_height="wrap_content"
            android:text="Service Provider"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/darkblue"
            android:textSize="14sp" />

        <Spinner
            android:id="@+id/spinner"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:entries="@array/service_arrays"
            android:prompt="@string/serviceprovid" />

        <TextView
            android:id="@+id/TextView02"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="100sp"
            android:layout_marginTop="5dp"
            android:text="Unit Master"
            android:textAppearance="?android:attr/textAppearanceSmall"
            android:textColor="@color/pumpkinorange"
            android:textSize="17sp" />

        <TextView
            android:id="@+id/TextView03"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="5sp"
            android:text="Unit No"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/darkblue"
            android:textSize="14sp" />

        <EditText
            android:id="@+id/unitNo"
            android:layout_width="275dp"
            android:layout_height="wrap_content"
            android:ems="10"
            android:selectAllOnFocus="true" />

        <TextView
            android:id="@+id/TextView04"
            android:layout_width="145dp"
            android:layout_height="wrap_content"
            android:text="IMEI No"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/darkblue"
            android:textSize="14sp" />

        <EditText
            android:id="@+id/imeiNo"
            android:layout_width="275dp"
            android:layout_height="wrap_content"
            android:ems="10" 
            android:selectAllOnFocus="true"/>

        <TextView
            android:id="@+id/vehicleNo"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="80sp"
            android:layout_marginTop="5dp"
            android:gravity="center"
            android:text="Vehicle Master"
            android:textAppearance="?android:attr/textAppearanceSmall"
            android:textColor="@color/pumpkinorange"
            android:textSize="17sp" />

        <TextView
            android:id="@+id/TextView06"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginTop="5dp"
            android:text="Vehicle No"
            android:textAppearance="?android:attr/textAppearanceMedium"
            android:textColor="@color/darkblue"
            android:textSize="14sp" />

        <EditText
            android:id="@+id/vehicleNo"
            android:layout_width="275dp"
            android:layout_height="wrap_content"
            android:ems="10" 
            android:selectAllOnFocus="true"/>

        <Button
            android:id="@+id/button1"
            android:layout_width="wrap_content"
            android:layout_height="34dp"
            android:layout_gravity="center"
            android:text="Save"
            android:textSize="15sp"
            android:textStyle="italic"
            android:typeface="normal" />

        <Button
            android:id="@+id/button2"
            style="?android:attr/buttonStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:layout_weight="1"
            android:text="Reset"
            android:textSize="15sp"
            android:textStyle="italic"
            android:typeface="normal" />

    </LinearLayout>

  </LinearLayout>
</ScrollView>

In this xml layout has four text fields and two buttons. while click on the reset button all the four textfields get cleared. How to define code for this in main activity.please Show explain me with code. 

A:

In your MainActivity, 
In your onCreate do this
Button reset = (Button)findViewById(R.id.reset);
Similarly Find your all textview here.
then,
reset.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {
        textview1.setText("");
        textview2.setText("");
        ......
        textview8.setText("");
    }
});

A:

btn.setOnClickListener(new OnClickListener(){
    @public void onClick(View view)
    {
        txt1.setText("");
        txt2.setText("");
        ...
        txtN.setText("");
    }
});

Also you can use array for your views.

A:

This is easier. I have a reset button and I reuse this code across different pages all I do is just change the mActivityABC basically calling the same page again as if you had clicked a next button it reloads and all EditText are clear. No arrays no setting of boxes nada!!
reset.setOnClickListener(new View.OnClickListener() {

    @Override
    public void onClick(View v) {
        if (v==reset) {
            startActivity(new Intent(myActivityABC.this, myActivityABC.class));
        }
    }
});

