android横向浏览图片,Android使用gallery和imageSwitch制作可左右循环滑动的图片浏览器...

在Android中，可以使用Gallery和ImageSwitcher来实现可左右循环滑动的图片浏览器。

首先，在布局文件中添加一个Gallery和一个ImageSwitcher：

<Gallery
    android:id="@+id/gallery"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true"
    android:gravity="center_vertical" />

<ImageSwitcher
    android:id="@+id/imageSwitcher"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_above="@id/gallery" />

然后，在Java代码中，需要为Gallery设置一个Adapter，并为ImageSwitcher设置一个ViewFactory。代码如下：

public class MainActivity extends AppCompatActivity {

    private Gallery mGallery;
    private ImageSwitcher mImageSwitcher;

    private int[] mImageIds = new int[]{R.drawable.image1, R.drawable.image2, R.drawable.image3};

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

        mGallery = (Gallery) findViewById(R.id.gallery);
        mImageSwitcher = (ImageSwitcher) findViewById(R.id.imageSwitcher);

        mGallery.setAdapter(new ImageAdapter(this));
        mImageSwitcher.setFactory(new ViewFactory() {
            @Override
            public View makeView() {
                ImageView imageView = new ImageView(MainActivity.this);
                imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
                return imageView;
            }
        });

        mGallery.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                mImageSwitcher.setImageResource(mImageIds[position % mImageIds.length]);
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }
        });
    }

    private class ImageAdapter extends BaseAdapter {

        private Context mContext;

        public ImageAdapter(Context context) {
            mContext = context;
        }

        @Override
        public int getCount() {
            return Integer.MAX_VALUE;
        }

        @Override
        public Object getItem(int position) {
            return null;
        }

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

        @Override
        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView imageView;
            if (convertView == null) {
                imageView = new ImageView(mContext);
                imageView.setLayoutParams(new Gallery.LayoutParams(200, 200));
                imageView.setScaleType(ImageView.ScaleType.FIT_XY);
            } else {
                imageView = (ImageView) convertView;
            }
            imageView.setImageResource(mImageIds[position % mImageIds.length]);
            return imageView;
        }
    }
}

这里的关键是设置Gallery的Adapter为一个无限循环的Adapter，以及在Gallery的OnItemSelectedListener中更新ImageSwitcher的图片资源。同时，ImageAdapter负责为Gallery提供每个Item的View。

这样，我们就可以实现一个左右循环滑动的图片浏览器了。