SmartTabLayout benutzerdefinierte Registerkartenansicht Aufblasen

Question

Die Idee besteht darin, mit der SmartTabLabyout-Bibliothek (https://github.com/ogaclejapan/SmartTabLayout) benutzerdefinierte Ansichten für jede Registerkarte aufzublasen. Aus irgendeinem Grund will es nicht funktionieren. Basis-Code ist wie folgt:

Aktivität:

public class MainActivity extends AppCompatActivity { 

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

     ViewPager mViewPager = (ViewPager) findViewById(R.id.pager); 
     SmartTabLayout viewPagerTab = (SmartTabLayout) findViewById(R.id.viewpagertab); 

     MainActivityViewPagerAdapter mPagerAdapter = new MainActivityViewPagerAdapter(getSupportFragmentManager(), this); 
     viewPagerTab.setCustomTabView(mPagerAdapter); 

     mViewPager.setAdapter(mPagerAdapter); 
     viewPagerTab.setViewPager(mViewPager); 
    } 
} 

Adapter:

public class MainActivityViewPagerAdapter extends FragmentPagerAdapter implements SmartTabLayout.TabProvider { 

    public enum MainActivityPages { 
     TAB_1(0, "Tab #1", R.drawable.tab_icon_1, TabFragment1.newInstance()), 
     TAB_2(1, "Tab #2", R.drawable.tab_icon_2, TabFragment2.newInstance()), 
     TAB_3(2, "Tab #3", R.drawable.tab_icon_3, TabFragment3.newInstance()); 

     public int index; 
     public String title; 
     public int resourceId; 
     public Fragment fragment; 

     MainActivityPages(int index, String title, int resourceId, Fragment fragment) { 
      this.index = index; 
      this.title = title; 
      this.resourceId = resourceId; 
      this.fragment = fragment; 
     } 
    } 

    public MainActivityViewPagerAdapter(FragmentManager fm, Context context) { 
     super(fm); 
     this.context = context; 
    } 

    @Override 
    public Fragment getItem(int position) { 
     return MainActivityPages.values()[position].fragment; 
    } 

    @Override 
    public int getCount() { 
     return MainActivityPages.values().length; 
    } 

    @Override 
    public CharSequence getPageTitle(int position) { 
     return MainActivityPages.values()[position].title; 
    } 

    @Override 
    public View createTabView(ViewGroup container, int position, PagerAdapter adapter) { 
     View v = LayoutInflater.from(this.context).inflate(R.layout.activity_main_tab, null); 

     if(v != null) { 
      ImageView icon = (ImageView) v.findViewById(R.id.activity_main_tab_icon); 
      icon.setImageResource(MainActivityPages.values()[position].resourceId); 
     } 

     return v; 
    } 
} 

activity_main.xml

<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
    xmlns:app="http://schemas.android.com/apk/res-auto" 
    xmlns:tools="http://schemas.android.com/tools" 
    android:layout_width="match_parent" 
    android:layout_height="match_parent" 
    android:background="#FFFFFF"> 

    <com.ogaclejapan.smarttablayout.SmartTabLayout 
     android:id="@+id/viewpagertab" 
     android:layout_width="match_parent" 
     android:layout_height="48dp" 
     app:stl_indicatorAlwaysInCenter="false" 
     app:stl_indicatorWithoutPadding="false" 
     app:stl_indicatorInFront="false" 
     app:stl_indicatorInterpolation="smart" 
     app:stl_indicatorGravity="bottom" 
     app:stl_indicatorColor="#40C4FF" 
     app:stl_indicatorThickness="4dp" 
     app:stl_indicatorWidth="auto" 
     app:stl_indicatorCornerRadius="2dp" 
     app:stl_overlineColor="#4D000000" 
     app:stl_overlineThickness="0dp" 
     app:stl_underlineColor="#FFFFFF" 
     app:stl_underlineThickness="0dp" 
     app:stl_dividerColor="#FFFFFF" 
     app:stl_dividerThickness="0dp" 
     app:stl_defaultTabBackground="?attr/selectableItemBackground" 
     app:stl_defaultTabTextAllCaps="true" 
     app:stl_defaultTabTextColor="#FC000000" 
     app:stl_defaultTabTextSize="12sp" 
     app:stl_defaultTabTextHorizontalPadding="16dp" 
     app:stl_defaultTabTextMinWidth="0dp" 
     app:stl_distributeEvenly="true" 
     app:stl_clickable="true" 
     app:stl_titleOffset="24dp" 
     app:stl_drawDecorationAfterTab="false" /> 

    <android.support.v4.view.ViewPager 
     android:id="@+id/pager" 
     android:layout_width="match_parent" 
     android:layout_height="wrap_content" 
     tools:context=".MainActivity" /> 

</LinearLayout> 

activity_main_tab.xml:

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

der obige Code erzeugt diese

java.lang.RuntimeException: Unable to start activity ComponentInfo{.activities.MainActivity}: java.lang.NullPointerException 
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2184) 
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233) 
    at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3724) 
    at android.app.ActivityThread.access$900(ActivityThread.java:135) 
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1202) 
    at android.os.Handler.dispatchMessage(Handler.java:102) 
    at android.os.Looper.loop(Looper.java:136) 
    at android.app.ActivityThread.main(ActivityThread.java:5001) 
    at java.lang.reflect.Method.invokeNative(Native Method) 
    at java.lang.reflect.Method.invoke(Method.java:515) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601) 
    at dalvik.system.NativeStart.main(Native Method) 
Caused by: java.lang.NullPointerException 
    at com.ogaclejapan.smarttablayout.SmartTabLayout.populateTabStrip(SmartTabLayout.java:398) 
    at com.ogaclejapan.smarttablayout.SmartTabLayout.setViewPager(SmartTabLayout.java:327) 
    at com.insertcoin.apps.vindr.activities.MainActivity$override.onCreate(MainActivity.java:63) 
    at com.insertcoin.apps.vindr.activities.MainActivity$override.access$dispatch(MainActivity.java) 
    at com.insertcoin.apps.vindr.activities.MainActivity.onCreate(MainActivity.java:0) 
    at android.app.Activity.performCreate(Activity.java:5231) 
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087) 
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2148) 
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2233)  
    at android.app.ActivityThread.handleRelaunchActivity(ActivityThread.java:3724)  
    at android.app.ActivityThread.access$900(ActivityThread.java:135)  
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1202)  
    at android.os.Handler.dispatchMessage(Handler.java:102)  
    at android.os.Looper.loop(Looper.java:136)  
    at android.app.ActivityThread.main(ActivityThread.java:5001)  
    at java.lang.reflect.Method.invokeNative(Native Method)  
    at java.lang.reflect.Method.invoke(Method.java:515)  
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:785)  
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:601)  
    at dalvik.system.NativeStart.main(Native Method) 

was bin ich dabei?

Answer 1

ok, es herausgefunden ...

SmartTabLayout.class klagt über null LinearLayout.LayoutParams, wenn Breite und Höhe einstellen, nach getLayoutParams() auf dem aufgeblasenen Ansicht aufrufen.

Um es zu lösen, muss der überhöhte Inhalt in ein LinearLayout verpackt werden. activity_main_tab.xml würde wie folgt aussehen:

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

    <ImageView 
     android:id="@+id/activity_main_tab_icon" 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" /> 

</LinearLayout> 

jedoch nicht genug ... nach der Ansicht in der createTabView, die folgende Zeile Aufblasen benötigt:

v.setLayoutParams(new LinearLayout.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT)); 

Dank für Ihre Zeit