Android Studio: Application crashes at start

Question

my application crashes at start and I have no idea why. I'm testing it on a real device (Samsung Galaxy S3 GT-I9300). Here is the exception:

EDIT:

So, that's what I've added to onCreate():

walking.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            travel_mode = "walking";
            walking.setImageResource(R.drawable.walking_sel);
            biking.setImageResource(R.drawable.regular_biking);
            driving.setImageResource(R.drawable.car_icon);
            transit.setImageResource(R.drawable.transit_icon);
        }
        });

    biking.setOnClickListener(new View.OnClickListener() {
        public void onClick(View v) {
            travel_mode = "biking";
            walking.setImageResource(R.drawable.walking);
            biking.setImageResource(R.drawable.regular_biking_sel);
            driving.setImageResource(R.drawable.car_icon);
            transit.setImageResource(R.drawable.transit_icon);
        }
    });

Before I've added this piece of code, everything worked correctly.

And here is AndroidManifest.xml:

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="lukssoftware.kaart" >
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="com.google.android.providers.gsf.permission.READ_GSERVICES" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-library android:name="com.google.android.maps" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >
    <meta-data
        android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />
    <meta-data
        android:name="com.google.android.maps.v2.API_KEY"
        android:value="***" />

    <meta-data android:name="com.google.android.gms.version"
        android:value="@integer/google_play_services_version" />

    <activity
        android:name="lukssoftware.kaart.kaart_welcome"
        android:screenOrientation="portrait"
        android:label="kaart" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

Any ideas? Thanks.

Answer 1

Please post more code and there is nothing to do with manifest here post layout xml and activity code where you have defined walking and biking findViews(). Just check it out that you have defined findViewsById of both walking and biking before you are calling setOnClickListener method.