Switch (Button) throws NullPointerException

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I know this question already exists, but I tried serveral solutions and none worked for me.

In my case, I need a Switch Button in the ActionBar.

• I tried to manually add a minSdk Verision


• I tried to use the id of the item in the defined xml

Here is some of my code:

mainactivity:

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_minepedia_main);

        switchButton = (Switch) findViewById(R.id.switch_button);

        //The following line throws an exception, because switchButton
        //is null, even though I tried to take it on the upper line.
        switchButton.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {

        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

        //The following is a local boolean variable
                if (isChecked) {
                    ONLINE_MODE_ENABLED = true;
                } else {
                    ONLINE_MODE_ENABLED = false;
                }

            }
        });
    }

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; --> main_actions.xml
    getMenuInflater().inflate(R.menu.main_actions, menu);
    return super.onCreateOptionsMenu(menu);
}

mainactivity_layout:

<RelativeLayout xmlns:android="http://ift.tt/nIICcg"
    xmlns:tools="http://ift.tt/LrGmb4"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:paddingLeft="@dimen/activity_horizontal_margin"
    android:paddingRight="@dimen/activity_horizontal_margin"
    android:paddingTop="@dimen/activity_vertical_margin"
    android:paddingBottom="@dimen/activity_vertical_margin"
    tools:context=".Minepedia_main">

    <LinearLayout
        android:layout_width="200dp"
        android:layout_height="match_parent"
        android:orientation="vertical"
        android:layout_centerInParent="true"
        android:gravity="center" >
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/items_button"
            android:onClick="startItemsMenu" />
        <Button
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="@string/about_button"
            android:onClick="startAboutScreen" />
        <LinearLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:gravity="bottom"
            android:paddingTop="50dp"
            android:orientation="vertical">
            <Button
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:text="@string/update_offline_button"
                android:onClick="startOfflineUpdate"/>
            <TextView
                android:layout_width="wrap_content"
                android:layout_height="wrap_content"
                android:textAppearance="?android:attr/textAppearanceSmall"
                android:text="@string/offline_sync_info"
                android:id="@+id/textView"
                android:layout_gravity="center_horizontal" />
        </LinearLayout>
    </LinearLayout>
</RelativeLayout>

main_actions.xml (menu):

<menu xmlns:android="http://ift.tt/nIICcg"
    xmlns:yourapp="http://ift.tt/GEGVYd" >
    <!-- Search, should appear as action button -->
    <item
        android:id="@+id/myswitch"
        android:title=""
        android:showAsAction="always"
        android:actionLayout="@layout/switch_layout"
        />
</menu>

switch_layout.xml:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://ift.tt/nIICcg"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <Switch
        android:id="@+id/switch_button"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:text=""
        android:textOff="Offline"
        android:textOn="Online"/>
</RelativeLayout>

asked 46 secs ago

TrudleR

422

Switch (Button) throws NullPointerException