ANDROID笔记:Gallery的简单使用

package com.example.adaptertest.gallery;

import android.app.Activity;
import android.os.Bundle;
import android.os.Handler;
import android.os.Handler.Callback;
import android.os.Message;
import android.view.View;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.Gallery;
import android.widget.Toast;

import com.example.adaptertest.R;

@SuppressWarnings("deprecation")
public class GalleryActivity extends Activity {
    int[] images = { R.drawable.a1, R.drawable.a2, R.drawable.a3, R.drawable.a4 };
    // 可以用AdapterViewFlipper替换
    Gallery gallery;
    int counter = 0;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.gallerytest);

        gallery = (Gallery) findViewById(R.id.gallery_id);
        gallery.setAdapter(new GalleryAdapter(GalleryActivity.this, images));
        handler.sendEmptyMessageDelayed(1, 5000);
        // 得到gallery选中的item的ID
        // gallery.getSelectedItemId();
        gallery.setOnItemClickListener(new OnItemClickListener() {

            @Override
            public void onItemClick(AdapterView<?> parent, View view,
                    int position, long id) {
                Toast.makeText(GalleryActivity.this, position + "",
                        Toast.LENGTH_LONG).show();
                // 移除消息队列（点击图片事停止图片自动滚动）
                handler.removeMessages(1);
            }
        });
        // 最前端的图片
        gallery.setOnItemSelectedListener(new OnItemSelectedListener() {

            @Override
            public void onItemSelected(AdapterView<?> parent, View view,
                    int position, long id) {
                Toast.makeText(GalleryActivity.this, position + "",
                        Toast.LENGTH_LONG).show();

            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {
                Toast.makeText(GalleryActivity.this, "nothing",
                        Toast.LENGTH_LONG).show();
            }
        });

    }

    Handler handler = new Handler(new Callback() {

        @Override
        public boolean handleMessage(Message msg) {
            if (msg.what == 1) {
                counter++;
                if (counter >= images.length) {
                    counter = 0;
                }
                // 更换图片
                gallery.setSelection(counter);
                // 继续发送消息到队列（类似递归）
                handler.sendEmptyMessageDelayed(1, 5000);
            }
            return true;
        }
    });
}

package com.example.adaptertest.gallery;

import android.content.Context;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.Gallery;
import android.widget.ImageView;
import android.widget.ImageView.ScaleType;

public class GalleryAdapter extends BaseAdapter {
    private int[] images;
    private Context context;

    public GalleryAdapter(Context convertView, int[] images) {
        this.context = convertView;
        this.images = images;

    }

    @Override
    public int getCount() {
        // TODO Auto-generated method stub
        return images.length;
    }

    @Override
    public Object getItem(int position) {
        // TODO Auto-generated method stub
        return images[position];
    }

    @Override
    public long getItemId(int position) {
        // TODO Auto-generated method stub
        return position;
    }

    @SuppressWarnings("deprecation")
    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        // TODO Auto-generated method stub
        ImageView imageView = new ImageView(context);
        imageView.setImageResource(images[position]);
        imageView.setScaleType(ScaleType.FIT_XY);
        imageView.setLayoutParams(new Gallery.LayoutParams(500, 500));
        return imageView;
    }

}

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

    <Gallery
        android:id="@+id/gallery_id"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:spacing="-20px"
        android:unselectedAlpha="150" />

</LinearLayout>
<!-- android:unselectedAlpha="150" 未被选择的图片的透明度 -->
<!-- android:spacing="-20px" 间隔 -->