how to create ripple effect for pre-lollipop

Question

How to apply ripple effect like this

i have put the dependencies in app/build.gradle

app/build.gradle

dependencies {
    compile 'com.github.traex.rippleeffect:library:1.3'
}

build.gradle

allprojects{
    repositories{
        jcenter()
        maven(url "https://jitpack.io" }

XML file:

<com.andexert.library.RippleView
        android:id="@+id/rect1"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
  <Button
      android:id="@+id/enterButton"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:text="Save your user name" />
 </com.andexert.library.RippleView>

Java class file

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.save_user);
    editText=(EditText) findViewById(R.id.userNameEditText);
    button=(Button) findViewById(R.id.enterButton);

    sharedPreferences=getSharedPreferences(SHARED_NAME_STRING, MODE_PRIVATE);
    String userNameString=sharedPreferences.getString(USER_NAME_STRING, "");

    editText.setText(userNameString);

    button.setOnClickListener(new View.OnClickListener() {

        @Override
        public void onClick(View v) {
            String string=editText.getText().toString();
            Intent intent=new Intent(SaveUser.this, MainActivity.class);
            intent.putExtra("user", string);

            SharedPreferences.Editor editor=sharedPreferences.edit();
            editor.putString(USER_NAME_STRING, string);
            editor.commit();

            startActivity(intent);

        }
    });
}

it works but my problem is another activity opens before the ripple effect completes and when I press back button the remaining ripple completes. how can I solve it??