aplikasi ini untuk menghitung luas lingkaran
#SKRIP DI MAIN CLASS
package
com.example.hitunglingkaran;
import
android.os.Bundle;
import
android.app.Activity;
import
android.view.Menu;
import
android.view.View;
import
android.view.View.OnClickListener;
import
android.widget.Button;
import
android.widget.EditText;
public
class
MainActivity
extends
Activity
implements
OnClickListener
{
private
EditText etJari, etHasil;
private
Button btnHitung;
@Override
protected
void
onCreate(Bundle savedInstanceState)
{
super
.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
etJari = (EditText) findViewById(R.id.editTextJari);
etHasil = (EditText) findViewById(R.id.editTextHasil);
btnHitung = (Button) findViewById(R.id.btnHitung);
btnHitung.setOnClickListener(
this
);
}
@Override
public
boolean
onCreateOptionsMenu(Menu menu)
{
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.activity_main, menu);
return
true
;
}
@Override
public
void
onClick(View v)
{
switch
(v.getId())
{
case
R.id.btnHitung:
etHasil.setText(String.valueOf(hitLuas(Float.parseFloat(etJari.getText().toString()))));
break
;
}
}
private
float
hitLuas(
float
jari)
{
float
luas;
luas = (
float
) (
3.14
* jari * jari);
return
luas;
}
}
#SKRIP DI LAYOUT
<
relativelayout
android:layout_height
=
"match_parent"
android:layout_width
=
"match_parent"
tools:context
=
".MainActivity"
xmlns:android
=
"http://schemas.android.com/apk/res/android"
xmlns:tools
=
"http://schemas.android.com/tools"
>
<
textview
android:id
=
"@+id/textView1"
android:layout_alignparenttop
=
"true"
android:layout_centerhorizontal
=
"true"
android:layout_height
=
"wrap_content"
android:layout_margintop
=
"65dp"
android:layout_width
=
"wrap_content"
android:text
=
"Jari"
>
<
edittext
android:ems
=
"10"
android:id
=
"@+id/editTextJari"
android:layout_below
=
"@+id/textView1"
android:layout_centerhorizontal
=
"true"
android:layout_height
=
"wrap_content"
android:layout_width
=
"wrap_content"
>
<
requestfocus
>
</
requestfocus
></
edittext
>
<
edittext
android:ems
=
"10"
android:id
=
"@+id/editTextHasil"
android:layout_centerhorizontal
=
"true"
android:layout_centervertical
=
"true"
android:layout_height
=
"wrap_content"
android:layout_width
=
"wrap_content"
>
<
button
android:id
=
"@+id/btnHitung"
android:layout_below
=
"@+id/editTextHasil"
android:layout_centerhorizontal
=
"true"
android:layout_height
=
"wrap_content"
android:layout_margintop
=
"34dp"
android:layout_width
=
"wrap_content"
android:text
=
"Hitung"
>
<
textview
android:id
=
"@+id/textView2"
android:layout_above
=
"@+id/editTextHasil"
android:layout_alignleft
=
"@+id/textView1"
android:layout_height
=
"wrap_content"
android:layout_marginbottom
=
"16dp"
android:layout_width
=
"wrap_content"
android:text
=
"Hasil"
>
</
textview
></
button
></
edittext
></
textview
></
relativelayout
>