App stops running after setting tablayout with ViewPager

Question

I created my own TabLayout menu (from an empty Activity) with a modified SectionPagerAdapter from a TabActivity project. I only changed the getItem() method and removed the page title method.

public Fragment getItem(int position) {
    switch (position)
    {
        case 0:
            HomeActivity home = new HomeActivity();
            return home;
        case 1:
            PayActivity pay = new PayActivity();
            return pay;
        case 2:
            VideoActivity video = new VideoActivity();
            return video;
        case 3:
            BillActivity bill = new BillActivity();
            return bill;
        default:
            return null;
    }
}

}

And after the execution of

    TabLayout tabToolbar = (TabLayout) findViewById(R.id.tabToolbar);
    ViewPager viewPager = (ViewPager) findViewById(R.id.container);

    SectionsPagerAdapter mSectionsPagerAdapter = new SectionsPagerAdapter(getSupportFragmentManager());
    viewPager.setAdapter(mSectionsPagerAdapter);
    tabToolbar.setupWithViewPager(viewPager);

my App has been stopped.

If I comment

tabToolbar.setupWithViewPager(viewPager);

than my menu doesn't work but I can swipe between my fragments within the ViewPager.

I want to swipe with my menu button and by swipping with my mousecursor as well.

If you need some more information or resources please let me know.

Edit:

The error log shows:

09-08 06:19:05.822 4207-4207/com.example.fdai3744.t_online20 E/AndroidRuntime: FATAL EXCEPTION: main
                                                                               Process: com.example.fdai3744.t_online20, PID: 4207
                                                                               java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.fdai3744.t_online20/com.example.fdai3744.t_online20.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.graphics.drawable.Drawable.setColorFilter(int, android.graphics.PorterDuff$Mode)' on a null object reference
                                                                                   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2665)
                                                                                   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726)
                                                                                   at android.app.ActivityThread.-wrap12(ActivityThread.java)
                                                                                   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477)
                                                                                   at android.os.Handler.dispatchMessage(Handler.java:102)
                                                                                   at android.os.Looper.loop(Looper.java:154)
                                                                                   at android.app.ActivityThread.main(ActivityThread.java:6119)
                                                                                   at java.lang.reflect.Method.invoke(Native Method)
                                                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                                                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
                                                                                Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.graphics.drawable.Drawable.setColorFilter(int, android.graphics.PorterDuff$Mode)' on a null object reference
                                                                                   at com.example.fdai3744.t_online20.MainActivity.onCreate(MainActivity.java:37)
                                                                                   at android.app.Activity.performCreate(Activity.java:6679)
                                                                                   at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
                                                                                   at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2618)
                                                                                   at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2726) 
                                                                                   at android.app.ActivityThread.-wrap12(ActivityThread.java) 
                                                                                   at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1477) 
                                                                                   at android.os.Handler.dispatchMessage(Handler.java:102) 
                                                                                   at android.os.Looper.loop(Looper.java:154) 
                                                                                   at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                                   at java.lang.reflect.Method.invoke(Native Method) 
                                                                                   at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                                   at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

2nd edit:

I found out that my adapter has no "public CharSequence getPageTitle(int position)" method.

Did you have some error from log? – Dario Sep 07 '17 at 20:21 — Dario, Sep 07 '17 at 20:21
Done! See below my question. – Ramón Wilhelm Sep 08 '17 at 06:22 — Ramón Wilhelm, Sep 08 '17 at 06:22

Aman Verma · Accepted Answer · 2017-09-08T14:51:29.327

1

add this line of code below setupwithviewpager;

viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabtoolbar));

EDIT :

i have updated the answer , you can refer this answer for tabs with icons only.

https://stackoverflow.com/a/32173670/5339829

edited Sep 08 '17 at 14:51

answered Sep 07 '17 at 20:28

Aman Verma

3,155
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No, I found out that I removed from my Adapter class the getPageTitle method. It works, but not with Icons. I want a FragmentAdapter which can also return Icons. – Ramón Wilhelm Sep 08 '17 at 14:34
1

you can search for tablayout with text and icons there are many libraries out there – Aman Verma Sep 08 '17 at 14:42
I am looking for an appropriate FragmentAdapter which I can also use only for icons without text. – Ramón Wilhelm Sep 08 '17 at 14:44
1

Thank you for your help! :) – Ramón Wilhelm Sep 08 '17 at 14:53

App stops running after setting tablayout with ViewPager

1 Answers1