galerie Android d'erreur drawable

Question

Je suis en train de mettre en œuvre l'exemple de la galerie Android de http://developer.android.com/resources/tutorials/views/hello-gallery.html

Je reçois cette erreur int oici lignes

 R.drawable.sample_1 cannot be resolved 
     R.drawable.sample_2 cannot be resolved, 
     R.drawable.sample_3 cannot be resolved, 
     R.drawable.sample_4 cannot be resolved, 
     R.drawable.sample_5 cannot be resolved, 
     R.drawable.sample_6 cannot be resolved, 
     R.drawable.sample_7 cannot be resolved 

Comment résoudre ce problème .Ce code est illustré ci-dessous.

HelloGallery.java

package com.HelloGallery; 

    import android.app.Activity; 
    import android.content.Context; 
    import android.content.res.TypedArray; 
    import android.os.Bundle; 
    import android.view.View; 
    import android.view.ViewGroup; 
    import android.widget.AdapterView; 
    import android.widget.BaseAdapter; 
    import android.widget.Gallery; 
    import android.widget.ImageView; 
    import android.widget.Toast; 
    import android.widget.AdapterView.OnItemClickListener; 
    import android.R.drawable; 

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

    Gallery g = (Gallery) findViewById(R.id.gallery); 
    g.setAdapter(new ImageAdapter(this)); 

    g.setOnItemClickListener(new OnItemClickListener() { 
     public void onItemClick(AdapterView parent, View v, int position, long id) { 
     Toast.makeText(HelloGalleryActivity.this, "" + position, Toast.LENGTH_SHORT).show(); 
     } 
    }); 


     } 

     public class ImageAdapter extends BaseAdapter { 
    int mGalleryItemBackground; 
    private Context mContext; 

    private Integer[] mImageIds = { 
     R.drawable.sample_1, 
     R.drawable.sample_2, 
     R.drawable.sample_3, 
     R.drawable.sample_4, 
     R.drawable.sample_5, 
     R.drawable.sample_6, 
     R.drawable.sample_7 
    }; 

    public ImageAdapter(Context c) { 
     mContext = c; 
     TypedArray a = obtainStyledAttributes(R.styleable.HelloGallery); 
     mGalleryItemBackground = a.getResourceId(
      R.styleable.HelloGallery_android_galleryItemBackground, 0); 
     a.recycle(); 
    } 

    public int getCount() { 
     return mImageIds.length; 
    } 

    public Object getItem(int position) { 
     return position; 
    } 

    public long getItemId(int position) { 
     return position; 
    } 

    public View getView(int position, View convertView, ViewGroup parent) { 
     ImageView i = new ImageView(mContext); 

     i.setImageResource(mImageIds[position]); 
     i.setLayoutParams(new Gallery.LayoutParams(150, 100)); 
     i.setScaleType(ImageView.ScaleType.FIT_XY); 
     i.setBackgroundResource(mGalleryItemBackground); 

     return i; 
    } 
     } 
    } 

main.mxml

<?xml version="1.0" encoding="utf-8"?> 
    <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 
     android:orientation="vertical" 
     android:layout_width="fill_parent" 
     android:layout_height="fill_parent" 
     > 
    <TextView 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
     android:text="@string/hello" 
     /> 
     <Gallery xmlns:android="http://schemas.android.com/apk/res/android" 
     android:id="@+id/gallery" 
     android:layout_width="fill_parent" 
     android:layout_height="wrap_content" 
    /> 
    </LinearLayout> 

attrs.mxml

<?xml version="1.0" encoding="utf-8"?> 
    <resources> 
     <declare-styleable name="HelloGallery"> 
    <attr name="android:galleryItemBackground" /> 
     </declare-styleable> 
    </resources> 

R.java

/* AUTO-GENERATED FILE. DO NOT MODIFY. 
    * 
    * This class was automatically generated by the 
    * aapt tool from the resource data it found. It 
    * should not be modified by hand. 
    */ 

    package com.HelloGallery; 

    public final class R { 
     public static final class attr { 
     } 
     public static final class drawable { 
    public static final int icon=0x7f020000; 
     } 
     public static final class id { 
    public static final int gallery=0x7f050000; 
     } 
     public static final class layout { 
    public static final int main=0x7f030000; 
     } 
     public static final class string { 
    public static final int app_name=0x7f040001; 
    public static final int hello=0x7f040000; 
     } 
     public static final class styleable { 
    /** Attributes that can be used with a HelloGallery. 
     <p>Includes the following attributes:</p> 
     <table> 
     <colgroup align="left" /> 
     <colgroup align="left" /> 
     <tr><th>Attribute</th><th>Description</th></tr> 
     <tr><td><code>{@link #HelloGallery_android_galleryItemBackground com.HelloGallery:android_galleryItemBackground}</code></td><td></td></tr> 
     </table> 
     @see #HelloGallery_android_galleryItemBackground 
     */ 
    public static final int[] HelloGallery = { 
     0x0101004c 
    }; 
    /** 
     <p>This symbol is the offset where the {@link com.HelloGallery.R.attr#android_galleryItemBackground} 
     attribute's value can be found in the {@link #HelloGallery} array. 
     @attr name android:android_galleryItemBackground 
    */ 
    public static final int HelloGallery_android_galleryItemBackground = 0; 
     }; 
    } 

Answer 1

Vous n'avez pas les fichiers dans votre répertoire/res/dossier drawable avec les noms

de sample_1.png ... _7 etc

Ceux-ci sont nécessaires pour remplir le widget, vous vous déclarez utiliser les ici:

private Integer[] mImageIds = { 
    R.drawable.sample_1, 
    R.drawable.sample_2, 
    R.drawable.sample_3, 
    R.drawable.sample_4, 
    R.drawable.sample_5, 
    R.drawable.sample_6, 
    R.drawable.sample_7 
}; 

C'est un tableau de nombres entiers, chaque entier est un ID relatif à une ressource drawable que vous avez créé dans votre/res/dossier drawable.

Si vous souhaitez obtenir de travailler rapidement copier juste et coller le fichier icon.png qui est déjà dans le répertoire/drawable/dossier et renommer la pâte sample_1.png, sample_2.png, sample_3.png etc

Si vous aviez ces fichiers, ils seraient liés dans votre fichier de classe R.java