可以在ViewPagerAdapter之外設置文字或背景顏色嗎？

在ViewPagerAdapter.class我有2個佈局（whereami.xml和mapview.xml），並使用LayoutInflater來爲每個視圖充氣instantiateItem()，通常我應該在instantiateItem()內設置所有內容（TextView，ImageView等等）。但對我來說，我真的需要在ViewPagerActivity的onCreate()到的setText或背景顏色延伸MapActivity可以在ViewPagerAdapter之外設置文字或背景顏色嗎？

是這樣，反正有沒有設定他們onCreate()？

P.S.我嘗試調試程序，發現該進程在調出onCreate()方法之前不會調用instantiateItem()。所以，視圖將不會創建，並且每當我嘗試設置Text時由於視圖爲空而導致程序關閉。

ViewPagerActivity

public class ViewPagerActivity extends MapActivity { 
    private ViewPagerAdapter adapter; 
    private ViewPager pager; 

    /** Called when the activity is first created. */ 
    @Override 
    public void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 

     adapter = new ViewPagerAdapter(this); 
     pager = (ViewPager) findViewById(R.id.viewpager); 
     TitlePageIndicator indicator = (TitlePageIndicator) findViewById(R.id.indicator); 
     pager.setAdapter(adapter); 
     indicator.setViewPager(pager); 


     //LinearLayout bgcolor = (LinearLayout)findViewById(R.id.mainlayout); 
     //bgcolor.setBackgroundColor(Color.Black); 
     //TextView text1 = (TextView)findViewById(R.id.text1); 
     //text1.setText("somevalue"); 

    } 


}

ViewPagerAdapter

public class ViewPagerAdapter extends PagerAdapter implements TitleProvider { 
    private final Context context; 
    private MapView mapView; 
    private MapController mapController; 
    private View view; 

    public ViewPagerAdapter(Context context) { 
    } 

    private static String[] titles = new String[] { "Page1", "Map" }; 

    @Override 
    public Object instantiateItem(View pager, final int position) { 
     LayoutInflater inflater = (LayoutInflater) context 
       .getSystemService(Context.LAYOUT_INFLATER_SERVICE); 

     if (position == 0) { 
      view = inflater.inflate(R.layout.whereami, null); 
      ((ViewPager) pager).addView(view, 0); 

     } 
     if (position == 1) { 
      view = inflater.inflate(R.layout.my_map_activity, null); 
      ((ViewPager) pager).addView(view, 0); 
      mapView = (MapView) view.findViewById(R.id.mapview); 

      mapController = mapView.getController(); 
      mapController.setZoom(14); 
     } 

     return view; 
    } 

}

whereami.xml

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

<TextView 
    android:id="@+id/text1" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:padding="8dp" 
    android:textSize="16sp" > 
</TextView> 
</LinearLayout>

來源

2012-02-08 April Smith

如果你知道onCreate()中的TextView應該是什麼，爲什麼不通過適配器的構造函數呢？

new ViewPagerAdapter(this, "TextToPass");

有了：

private String toDisplay; 
public ViewPagerAdapter(Context context, String toDisplay) { 
    this.toDispay = toDisplay; 
}

和：

view = inflater.inflate(R.layout.whereami, null); 
TextView textView = view.findViewById(R.id.text1); 
textView.setText(toDisplay);

來源

2012-02-08 15:05:45 Graeme

可以在ViewPagerAdapter之外設置文字或背景顏色嗎？

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