android - 如何使图库项目的背景颜色透明并更改边框样式和大小？

Question

这就是我想要的

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就是出现“我要修改”的样子

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1 - 如何将图库中项目的背景更改为透明？2 - 如何删除画廊中每个项目周围的边框？3 - 如何以正常尺寸显示它们“不被拉伸(stretch)”？

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这里是使用的代码.java

public class Search extends Activity {
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.options);
          Gallery gallery = (Gallery) findViewById(R.id.gallery1);
            gallery.setAdapter(new ImageAdapter(this));

            gallery.setOnItemClickListener(new OnItemClickListener() {
                public void onItemClick(AdapterView parent, View v, int   position, long id) {
                    Toast.makeText(Search.this, "" + position, Toast.LENGTH_SHORT).show();
                }
            });
}
public class ImageAdapter extends BaseAdapter {
        int mGalleryItemBackground;
        private Context mContext;

        private Integer[] mImageIds = {
                R.drawable.animals,
                R.drawable.automotive,
                R.drawable.directory,
                R.drawable.homeoffice,
                R.drawable.hobbies,
                R.drawable.mother,
                R.drawable.jobs,
                R.drawable.realestate,
                R.drawable.technology
        };

        public ImageAdapter(Context c) {
            mContext = c;
            TypedArray attr =   mContext.obtainStyledAttributes(R.styleable.HelloGallery);
            mGalleryItemBackground = attr.getResourceId(
                    R.styleable.HelloGallery_android_galleryItemBackground,17170445 );
            attr.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 imageView = new ImageView(mContext);

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

            return imageView;
        }
    }
}

Answer 1

您必须调整作为图库项目创建的 ImageView 的参数。在这种情况下，您必须更改 getView() 函数的内容。

1. 设置合适的背景。试试 imageView.setBackgroundColor(Color.TRANSPARENT)。它将背景设置为透明并移除项目周围的边框(边框由背景描述)。

2. 在 1 中解决。

3. 您可以通过更改 imageView.setScaleType() 函数中的比例类型来影响(或不)拉伸(stretch)图像的方式(有关更多信息，请参阅 ImageView.ScaleType 的文档细节)。试试 imageView.setScaleType(ImageView.ScaleType.FIT_CENTER)。您还可以设置“更好”的布局参数(尝试 imageView.setLayoutParams(new Gallery.LayoutParams(Gallery.LayoutParams.WRAP_CONTENT, Gallery.LayoutParams.WRAP_CONTENT)))。

总而言之，getView() 函数应该是这样的:

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

    imageView.setImageResource(mImageIds[position]);
    imageView.setLayoutParams(new Gallery.LayoutParams(150, 100));
    imageView.setScaleType(ImageView.ScaleType.FIT_CENTER);
    imageView.setBackgroundColor(Color.TRANSPARENT);  

    return imageView;
}