how to center relative layout in linearlayout

Question

I want to center horizontally and vertically block L3 on this image, can you help me with the layout structure to use. ON the right side is current structure of the menu. Thanks.

Here is the layout.xml code:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/BaseLayout"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="@color/mainmenu_background" >

<ImageView
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:scaleType="fitXY"
    android:src="@drawable/main_menu_background" />

<LinearLayout
    android:id="@+id/l1"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <!-- Top menu -->

    <LinearLayout
        android:id="@+id/l2"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:orientation="horizontal" >

        <RelativeLayout
            android:id="@+id/TopMenuHolder"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:background="@drawable/main_menu_background_header"
            android:gravity="left"
            android:orientation="horizontal"
            android:visibility="visible" >

            <ImageView
                android:id="@+id/logo"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerVertical="true"
                android:src="@drawable/logo" />

            <LinearLayout
                android:id="@+id/TopRightButtonsHolder"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentRight="true"
                android:layout_centerVertical="true"
                android:orientation="horizontal"
                android:visibility="visible" >

                <RelativeLayout
                    android:id="@+id/sinscrire"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" >

                    <ImageButton
                        android:id="@+id/login_registerbutton"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerVertical="true"
                        android:background="@color/transparent"
                        android:scaleType="fitXY"
                        android:src="@drawable/main_menu_sinscrire_button" />

                    <TextView
                        android:id="@+id/sinscrire_text"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerHorizontal="true"
                        android:layout_centerVertical="true"
                        android:text="@string/cpr_sinscrite_title_text"
                        android:textColor="@color/cpr_menubutton_black"
                        android:textSize="@dimen/cpr_small_menubutton_title_text_size"
                        android:textStyle="bold|italic" />
                </RelativeLayout>

                <RelativeLayout
                    android:id="@+id/connexion"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" >

                    <ImageButton
                        android:id="@+id/login_loginbutton"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerVertical="true"
                        android:background="@color/transparent"
                        android:scaleType="fitXY"
                        android:src="@drawable/main_menu_logout_button" />

                    <TextView
                        android:id="@+id/connexion_text"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerHorizontal="true"
                        android:layout_centerVertical="true"
                        android:text="@string/cpr_connexion_title_text"
                        android:textColor="@color/cpr_menubutton_white"
                        android:textSize="@dimen/cpr_small_menubutton_title_text_size"
                        android:textStyle="bold|italic" />
                </RelativeLayout>
            </LinearLayout>
        </RelativeLayout>
    </LinearLayout>
    <!-- End of Top menu -->


    <!-- Middle menu -->

    <LinearLayout
        android:id="@+id/l3"
        android:layout_width="wrap_content"
        android:layout_height="fill_parent"
        android:layout_gravity="center_vertical|center_horizontal"
        android:orientation="vertical" >

        <RelativeLayout
            android:id="@+id/MiddleMenu"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="center_vertical|center_horizontal" >

            <LinearLayout
                android:id="@+id/MiddleLeftButtonsHolder"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:gravity="left"
                android:orientation="horizontal"
                android:visibility="visible" >

                <RelativeLayout
                    android:id="@+id/Parametres"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" >

                    <ImageButton
                        android:id="@+id/optionsmenu_settings"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerVertical="true"
                        android:background="@color/transparent"
                        android:scaleType="fitXY"
                        android:src="@drawable/main_menu_options_button" />

                    <LinearLayout
                        android:id="@+id/options_container"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerInParent="true"
                        android:layout_gravity="left"
                        android:orientation="horizontal" >

                        <ImageView
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:background="@drawable/options_icon" />

                        <TextView
                            android:id="@+id/parametres_text"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="@string/cpr_parametres_title_text"
                            android:textColor="@color/cpr_menubutton_black"
android:textSize="@dimen/cpr_small_menubutton_title_text_size"
                            android:textStyle="bold|italic" />
                    </LinearLayout>
                </RelativeLayout>

                <RelativeLayout
                    android:id="@+id/Aide"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" >

                    <ImageButton
                        android:id="@+id/optionsmenu_info"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerVertical="true"
                        android:background="@color/transparent"
                        android:scaleType="fitXY"
                        android:src="@drawable/main_menu_help_button" />

                    <LinearLayout
                        android:id="@+id/help_container"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerInParent="true"
                        android:layout_gravity="left"
                        android:orientation="horizontal" >

                        <ImageView
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:background="@drawable/help_icon" />

                        <TextView
                            android:id="@+id/aide_text"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="@string/cpr_aide_title_text"
android:textColor="@color/cpr_menubutton_black"
android:textSize="@dimen/cpr_small_menubutton_title_text_size"
                            android:textStyle="bold|italic" />
                    </LinearLayout>
                </RelativeLayout>
            </LinearLayout>

            <LinearLayout
                android:id="@+id/MiddleRightButtonsHolder"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_centerVertical="true"
                android:layout_toRightOf="@id/MiddleLeftButtonsHolder"
                android:orientation="horizontal"
                android:visibility="visible" >

                <RelativeLayout
                    android:id="@+id/Caisse"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content" >

                    <ImageButton
                        android:id="@+id/cashiericon"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerVertical="true"
                        android:background="@color/transparent"
                        android:scaleType="fitXY"
                        android:src="@drawable/main_menu_cashier_button" />

                    <LinearLayout
                        android:id="@+id/caisse_container"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:layout_centerInParent="true"
                        android:layout_gravity="left"
                        android:orientation="horizontal" >

                        <ImageView
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:background="@drawable/cashier_icon" />

                        <TextView
                            android:id="@+id/caisse_text"
                            android:layout_width="wrap_content"
                            android:layout_height="wrap_content"
                            android:text="@string/cpr_caisse_title_text"
                            android:textColor="@color/cpr_menubutton_white"
android:textSize="@dimen/cpr_small_menubutton_title_text_size"
                            android:textStyle="bold|italic" />
                    </LinearLayout>
                </RelativeLayout>
            </LinearLayout>
        </RelativeLayout>
        <!-- End of Middle menu -->


        <!-- Main menu -->

        <RelativeLayout
            android:id="@+id/MainMenu"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_below="@id/MiddleMenu"
            android:layout_marginBottom="5dp"
            android:layout_marginLeft="10dp"
            android:layout_marginRight="10dp"
            android:layout_marginTop="10dp" >

            <ImageView
                android:id="@+id/main_menu_black_rect"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_alignParentLeft="true"
                android:layout_centerVertical="true"
                android:scaleType="fitXY"
                android:src="@drawable/main_menu_black_rect" />

            <RelativeLayout
                android:id="@+id/play_for_real"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_marginLeft="15dp"
                android:layout_marginTop="20dp" >

                <ImageButton
                    android:id="@+id/realmoneybutton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerVertical="true"
                    android:background="@color/transparent"
                    android:scaleType="fitStart"
                    android:src="@drawable/main_menu_play_for_real_button" />

                <ImageView
                    android:id="@+id/play_for_real_img_icon"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignBottom="@id/realmoneybutton"
                    android:layout_alignRight="@id/realmoneybutton"
                    android:background="@color/transparent"
                    android:src="@drawable/main_menu_play_for_real_button_icon" />

                <LinearLayout
                    android:id="@+id/play_for_money_text_container"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_margin="5dp"
                    android:orientation="vertical" >

                    <TextView
                        android:id="@+id/play_for_real_title"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="@string/cpr_play_for_real_title_text"
                        android:textColor="@color/cpr_menubutton_white"
                        android:textSize="@dimen/cpr_menubutton_title_text_size"
                        android:textStyle="bold" />

                    <TextView
                        android:id="@+id/play_for_real_desc"
                        android:layout_width="221dp"
                        android:layout_height="wrap_content"
                        android:text="@string/cpr_play_for_real_title_desc"
                        android:textColor="@color/cpr_menubutton_white"
                        android:textSize="@dimen/cpr_menubutton_desc_text_size" />
                </LinearLayout>
            </RelativeLayout>

            <RelativeLayout
                android:id="@+id/play_for_fun"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/play_for_real"
                android:layout_marginLeft="15dp"
                android:layout_marginTop="5dp" >

                <ImageButton
                    android:id="@+id/playmoneybutton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerVertical="true"
                    android:background="@color/transparent"
                    android:scaleType="fitXY"
                    android:src="@drawable/main_menu_play_for_fun_button" />

                <ImageView
                    android:id="@+id/play_for_fun_img_icon"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_alignBottom="@id/playmoneybutton"
                    android:layout_alignRight="@id/playmoneybutton"
                    android:background="@color/transparent"
                    android:src="@drawable/main_menu_play_for_fun_button_icon" />

                <LinearLayout
                    android:id="@+id/play_for_fun_text_container"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_margin="5dp"
                    android:orientation="vertical" >

                    <TextView
                        android:id="@+id/play_for_fun_title"
                        android:layout_width="wrap_content"
                        android:layout_height="wrap_content"
                        android:text="@string/cpr_play_for_fun_title_text"
                        android:textColor="@color/cpr_menubutton_white"
                        android:textSize="@dimen/cpr_menubutton_title_text_size"
                        android:textStyle="bold" />

                    <TextView
                        android:id="@+id/play_for_fun_desc"
                        android:layout_width="221dp"
                        android:layout_height="wrap_content"
                        android:text="@string/cpr_play_for_fun_title_desc"
                        android:textColor="@color/cpr_menubutton_white"
                        android:textSize="@dimen/cpr_menubutton_desc_text_size" />
                </LinearLayout>
            </RelativeLayout>

            <RelativeLayout
                android:id="@+id/tutoriel"
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:layout_below="@id/play_for_fun"
                android:layout_marginLeft="15dp"
                android:layout_marginTop="5dp" >

                <ImageButton
                    android:id="@id/previewbutton"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerVertical="true"
                    android:background="@color/transparent"
                    android:scaleType="fitXY"
                    android:src="@drawable/main_menu_tutorial_button" />

                <TextView
                    android:id="@+id/tutoriel_title"
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:layout_centerVertical="true"
                    android:text="@string/cpr_tutoriel_title_text"
                    android:textColor="@color/cpr_menubutton_white"
                    android:textSize="@dimen/cpr_menubutton_title_text_size"
                    android:textStyle="bold" />
            </RelativeLayout>
        </RelativeLayout>
    </LinearLayout>
    <!-- End of Main menu -->

</LinearLayout>
<!-- End of Main Container -->

</RelativeLayout>

Answer 1

Here is a Linear Layout with a Relative Layout centered inside.

Move your code from the "l3" layout to the "l4" layout:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/l1"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <LinearLayout
        android:id="@+id/l2"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#56a"
        android:orientation="vertical" >

        <TextView
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_gravity="center"
            android:text="l2" />
    </LinearLayout>

    <RelativeLayout
        android:id="@+id/l3"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="#a56" >

        <TextView
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="l3" />

        <RelativeLayout
            android:id="@+id/l4"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:layout_centerHorizontal="true"
            android:layout_centerVertical="true"
            android:background="#5a6" >

            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:text="l4" />

        </RelativeLayout>
    </RelativeLayout>

</LinearLayout>