文本定製的無限滾動畫廊

Question

我有一個基於這個例子無限空間：

http://blog.blundell-apps.com/infinite-scrolling-gallery/，每一件事運行正常：

正是我想將文本應用到每個圖像和能夠自定義文本太如圖所示下來的圖像，並每個形象diffrenet文本比別人，但仍然沒有成功與無限畫廊做

我試着用下面的代碼，但它給了我強制關閉運行應用程序時，

（也許有錯碼我寫的，但是我仍然在學習JAVA和BEGINER在Android開發）。

請任何幫助和建議，將不勝感激

謝謝你。

我的代碼：

GALLERY_ITEM

<?xml version="1.0" encoding="utf-8"?> 
    <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" 
     android:id="@+id/LinearLayout01" 
     android:layout_width="fill_parent" 
     android:layout_height="fill_parent" 
     android:orientation="vertical" 
     android:gravity="center_horizontal"> 
    <ImageView 
    android:id="@+id/image" 
    android:layout_height="300dp" 
    android:layout_width="fill_parent"   /> 
    <TextView 
    android:text="TextView" 
    android:id="@+id/textView1" 
    android:layout_width="fill_parent" 
    android:layout_height="fill_parent" 
    android:textColor="#B22222"  
    android:textSize="20dp" 
    android:gravity="center" 
    android:layout_margin="30dp" 
    android:layout_below="@+id/image"   /> 

然後在InfiniteScrollingGalleryActivity.java變化如下：

public class InfiniteScrollingGalleryActivity extends Activity { 

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

    InfiniteGallery galleryOne = (InfiniteGallery) findViewById(R.id.galleryOne); 
    galleryOne.setAdapter(new InfiniteGalleryAdapter(this));  
     }  } 

然後改變無限GalleryResourceAdapter.java如下：

public class InfiniteGalleryAdapter extends BaseAdapter { 

    /** The width of each child image */ 
    private static final int G_ITEM_WIDTH = 360; 
    /** The height of each child image */ 
    private static final int G_ITEM_HEIGHT = 240; 
    /** The context your gallery is running in (usually the activity) */ 
     private Context mContext; 
     private int imageWidth; 
     private int imageHeight; 
     private int[] imageIds; 

     public InfiniteGalleryAdapter(Context c, int[] imageIds) { 
      this.mContext = c; 
      this.imageIds = imageIds; } 

     public int getCount() { 
     return Integer.MAX_VALUE;  } 
     public Object getItem(int position) { 
     return position; } 
     public long getItemId(int position) { 
     return position; }  

     private Activity activity; 
     private LayoutInflater inflater=null; 

    public InfiniteGalleryAdapter(Activity a) {  
     final int[] imageIds; 
    activity = a; 
    inflater = (LayoutInflater)activity.getSystemService 
      Context.LAYOUT_INFLATER_SERVICE);   } 
     public class ViewHolder{  
     public TextView text;  
     public ImageView image;   } 
    public View getView(int position, View convertView, ViewGroup parent) { 
    ImageView i = getImageView(); 
try { 

    int itemPos = (position % imageIds.length); 

    i.setImageResource(imageIds[itemPos]); 

    ((BitmapDrawable) i.getDrawable()).setAntiAlias(true); } 

      catch (OutOfMemoryError e) { 

    Log.e("InfiniteGalleryResourceAdapter", "Out of memory creating imageview. 
     Using empty view.", e);  } 

    View vi=convertView; 

     ViewHolder holder; 

    if(convertView==null){ 
     vi = inflater.inflate(R.layout.gallery_items, null); 
    holder=new ViewHolder(); 
    holder.text=(TextView)vi.findViewById(R.id.textView1); 
    holder.image=(ImageView)vi.findViewById(R.id.image);  
    vi.setTag(holder);    } 
    else  
    holder=(ViewHolder)vi.getTag(); 
    holder.text.setText(name[position]); 

    final int stub_id=images[position]; 
    holder.image.setImageResource(stub_id); 
    return vi;   } 

    private int[] images = { 
     R.drawable.one_1, R.drawable.one_4, 
     R.drawable.one_2, R.drawable.one_5, 
     R.drawable.one_3     }; 

    private String[] name = { 
     "this is my car", "i love this", 
     "please hekp me", "im in park", 
     " This is nice place to visit.",   }; 


    private ImageView getImageView() { 
     setImageDimensions(); 
    ImageView i = new ImageView(mContext); 
    i.setLayoutParams(new Gallery.LayoutParams(imageWidth, imageHeight)); 
    i.setScaleType(ScaleType.CENTER_INSIDE);  return i;  } 

private void setImageDimensions() { 
     if (imageWidth == 0 || imageHeight == 0) { 
    imageWidth = AndroidUtils.convertToPix(mContext, G_ITEM_WIDTH); 
    imageHeight = AndroidUtils.convertToPix(mContext,G_ITEM_HEIGHT); 
     }   }  
      } 

這是logcat的錯誤：

04-10 02:25:13.057: E/AndroidRuntime(12302): FATAL EXCEPTION: main 
04-10 02:25:13.057: E/AndroidRuntime(12302): java.lang.NullPointerException 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.infinite.test.AndroidUtils.convertToPix(AndroidUtils.java:11) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.infinite.test.InfiniteGalleryAdapter.setImageDimensions 
(InfiniteGalleryAdapter.java:131) 
4-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.infinite.test.InfiniteGalleryAdapter.getImageView 
(InfiniteGalleryAdapter.java:117) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.infinite.test.InfiniteGalleryAdapter.getView(InfiniteGalleryAdapter.java:66) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.AbsSpinner.onMeasure(AbsSpinner.java:192) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.View.measure(View.java:8366) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1017) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.LinearLayout.measureVertical(LinearLayout.java:386) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.View.measure(View.java:8366) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.ViewGroup.measureChildWithMargins(viewGroup.java:3138) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.View.measure(View.java:8366) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.LinearLayout.measureVertical(LinearLayout.java:531) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.LinearLayout.onMeasure(LinearLayout.java:309) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.View.measure(View.java:8366) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:3138) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.widget.FrameLayout.onMeasure(FrameLayout.java:250) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.View.measure(View.java:8366) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.ViewRoot.performTraversals(ViewRoot.java:844) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.view.ViewRoot.handleMessage(ViewRoot.java:1865) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.os.Handler.dispatchMessage(Handler.java:99) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.os.Looper.loop(Looper.java:123) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at android.app.ActivityThread.main(ActivityThread.java:3687) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at java.lang.reflect.Method.invokeNative(Native Method) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at java.lang.reflect.Method.invoke (Method.java:507) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:842) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:600) 
04-10 02:25:13.057: E/AndroidRuntime(12302): 
at dalvik.system.NativeStart.main(Native Method) 
04-10 02:25:13.061: E/(129): Dumpstate > /data/log/dumpstate_app_error 

Answer 1

問題似乎在於與上下文變量和圖像的位置。請爲您的適配器嘗試以下代碼：

public class InfiniteGalleryAdapter extends BaseAdapter { 
/** The width of each child image */ 
private static final int G_ITEM_WIDTH = 360; 
/** The height of each child image */ 
private static final int G_ITEM_HEIGHT = 240; 
/** The context your gallery is running in (usually the activity) */ 
private Context mContext;  
private int imageWidth;  
private int imageHeight; 
private int[] imageIds;  
public InfiniteGalleryAdapter(Context c, int[] imageIds) {  
    this.mContext = c;   
    this.imageIds = imageIds; } 
public int getCount() { 
    return Integer.MAX_VALUE; 
}  
public Object getItem(int position) { 
    return position; } 
public long getItemId(int position) { 
    return position; }  
//private Activity activity; 
private LayoutInflater inflater=null; 
public InfiniteGalleryAdapter(Context a) { 
    final int[] imageIds; 
    //activity = a; 
    this.mContext = a; 
    inflater = (LayoutInflater)mContext.getSystemService (  Context.LAYOUT_INFLATER_SERVICE); 
}   public class ViewHolder{ 
    public TextView text; 
    public ImageView image; 
}  

private int[] images = { 
     R.drawable.one_1, R.drawable.one_4, 
     R.drawable.one_2, R.drawable.one_5, 
     R.drawable.one_3    
};  
private String[] name = { 
     "this is my car", "i love this", 
     "please hekp me", "im in park",  
     " This is nice place to visit.", 
};  
public View getView(int position, View convertView, ViewGroup parent) { 
    ImageView i = getImageView(); 
    int itemPos = (position % images.length); 
    try {  

     i.setImageResource(images[itemPos]); 
     ((BitmapDrawable) i.getDrawable()).setAntiAlias(true); } 
    catch (OutOfMemoryError e) {  
     Log.e("InfiniteGalleryResourceAdapter", "Out of memory creating imageview.   Using empty view.", e); 
    }   View vi=convertView;  
    ViewHolder holder; 
    if(convertView==null){ 
     vi = inflater.inflate(R.layout.gallery_items, null); 
     holder=new ViewHolder();  
     holder.text=(TextView)vi.findViewById(R.id.textView1); 
     holder.image=(ImageView)vi.findViewById(R.id.image); 
     vi.setTag(holder);  
    }  else 
     holder=(ViewHolder)vi.getTag(); 
    holder.text.setText(name[itemPos]); 
    final int stub_id=images[itemPos]; 
    holder.image.setImageResource(stub_id); 
    return vi;  
} 

private ImageView getImageView() { 
    setImageDimensions(); 

    ImageView i = new ImageView(mContext); 
    i.setLayoutParams(new Gallery.LayoutParams(imageWidth, imageHeight)); 
    i.setScaleType(ScaleType.CENTER_INSIDE); 
    return i;  } 
private void setImageDimensions() { 
    if (imageWidth == 0 || imageHeight == 0) {   
     imageWidth = AndroidUtils.convertToPix(mContext, G_ITEM_WIDTH); 
     imageHeight = AndroidUtils.convertToPix(mContext,G_ITEM_HEIGHT); 
    }   }     }