import android.app.Activity; import android.graphics.Color; import android.os.Bundle; import android.widget.TextView; /*欲在Layout里使用Gallery widget，必须引用这些模块*/ import android.content.Context; import android.widget.Gallery; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; public class EX03_15 extends Activity { private TextView mTextView01; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); mTextView01 = (TextView) findViewById(R.id.myTextView01); mTextView01.setText(getString(R.string.str_txt1)); mTextView01.setTextColor(Color.BLUE); ((Gallery) findViewById(R.id.myGallery1)) .setAdapter(new ImageAdapter(this)); } public class ImageAdapter extends BaseAdapter { /* 类成员 myContext为Context父类 */ private Context myContext; /* 使用android.R.drawable里的图片作为图库来源，类型为整数数组 */ private int[] myImageIds = { android.R.drawable.btn_minus, android.R.drawable.btn_radio, android.R.drawable.ic_lock_idle_low_battery, android.R.drawable.ic_menu_camera }; /* 构造器只有一个参数，即要存储的Context */ public ImageAdapter(Context c) { this.myContext = c; } /* 返回所有已定义的图片总数量 */ public int getCount() { return this.myImageIds.length; } /* 利用getItem方法，取得目前容器中图像的数组ID */ public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } /* 取得目前欲显示的图像View，传入数组ID值使之读取与成像 */ public View getView(int position, View convertView, ViewGroup parent) { /* 创建一个ImageView对象 */ ImageView i = new ImageView(this.myContext); i.setImageResource(this.myImageIds[position]); i.setScaleType(ImageView.ScaleType.FIT_XY); /* 设置这个ImageView对象的宽高，单位为dip */ i.setLayoutParams(new Gallery.LayoutParams(120, 120)); return i; } /* 依据距离中央的位移量 利用getScale返回views的大小(0.0f to 1.0f) */ public float getScale(boolean focused, int offset) { /* Formula: 1 / (2 ^ offset) */ return Math.max(0, 1.0f / (float) Math.pow(2, Math.abs(offset))); } } } <Gallery android:id="@+id/myGallery1" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="bottom" />
