Gallery of Android

1. Add Galleryactivity_main.xml to the xml layout.

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:layout_width="match_parent"    android:layout_height="match_parent">    <Gallery        android:id="@+id/gallery"        android:layout_width="match_parent"        android:layout_height="match_parent"/></LinearLayout>

2. Custom ImageAdapterImageAdapter. java

Package com. example. gallery; import java. util. list; import android. content. context; import android. content. res. typedArray; import android. view. view; import android. view. viewGroup; import android. widget. baseAdapter; import android. widget. gallery; import android. widget. imageView; @ SuppressWarnings ("deprecation") public class ImageAdapter extends BaseAdapter {private Context context; private List <Integer> list; private TypedArray typedArray; private int item_background; public ImageAdapter (Context context Context, list <Integer> list) {this. context = context; this. list = list; this. typedArray = context. obtainStyledAttributes (R. styleable. gallery_style); item_background = typedArray. getResourceId (R. styleable. gallery_style_android_galleryItemBackground, 0); typedArray. recycle () ;}@ Override public int getCount () {return list. size () ;}@ Override public Object getItem (int position) {return position ;}@ Override public long getItemId (int position) {return position ;} @ Override public View getView (int position, View convertView, ViewGroup parent) {ImageView imageView = new ImageView (context); // sets the imageView of the displayed image. setImageResource (list. get (position); // you can specify the size of the image to be scaled. setScaleType (ImageView. scaleType. FIT_XY); // sets the layout parameter imageView. setLayoutParams (new Gallery. layoutParams (150,100); // sets the background border imageView. setBackgroundResource (item_background); return imageView ;}}

3. The background parameter res/values/attrs. xml of each ImageView

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

4. Bind data and set the listener MainActivity. java in MainActivity

Package com. example. gallery; import java. util. arrayList; import android. app. activity; import android. OS. bundle; import android. view. view; import android. widget. adapterView; import android. widget. gallery; import android. widget. toast; @ SuppressWarnings ("deprecation") public class MainActivity extends Activity {@ Override protected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState ); SetContentView (R. layout. activity_main); Gallery gallery = (Gallery) findViewById (R. id. gallery); ArrayList <Integer> list = new ArrayList <Integer> (); list. add (R. drawable. img1); list. add (R. drawable. img2); list. add (R. drawable. img3); list. add (R. drawable. img4); list. add (R. drawable. img5); list. add (R. drawable. img6); list. add (R. drawable. img7); ImageAdapter adapter = new ImageAdapter (this, list); gallery. setAdapter (Adapter); gallery. setOnItemSelectedListener (new AdapterView. OnItemSelectedListener () {@ Override public void onItemSelected (AdapterView <?> Parent, View v, int position, long id) {Toast. makeText (getApplicationContext (), "selected:" + String. valueOf (position), Toast. LENGTH_SHORT ). show () ;}@ Override public void onNothingSelected (AdapterView <?> Arg0) {// No response here }});}}

5. Image resource note: it is best to use a png image. Because jpg is a compressed image, decompression in android may cause memory overflow errors.6. Result Display


Note: Please indicate the source for reprinting. After all, the code is coded one by one ~