选择照片

点击蓝色选择图片

public class SelectorPictureGridView extends GridView {

    private SelectorPictureAdapter selectorPictureAdapter;
    private int spacing = 8;
    private int numColumns = 3;

    public SelectorPictureGridView(Context context) {
        this(context, null);
    }

    public SelectorPictureGridView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
    }

    public SelectorPictureGridView(Context context, AttributeSet attrs, int defStyleAttr) {
        super(context, attrs, defStyleAttr);

        setNumColumns(numColumns);
        setGravity(Gravity.CENTER);
        spacing = px2dp(spacing);
        setVelocityScale(spacing);
        setHorizontalSpacing(spacing);
        setMargins(this, spacing, spacing, spacing, spacing);
    }

    private int getItemSize(){
        DisplayMetrics dm = getResources().getDisplayMetrics();
        int width = dm.widthPixels;
        return width / numColumns - (spacing * 4);
    }

    private int px2dp(float pxValue) {
        final float scale = getResources().getDisplayMetrics().density;
        return (int) (pxValue / scale + 0.5f);
    }

    private void setMargins(View v, int l, int t, int r, int b) {
        if (v.getLayoutParams() instanceof ViewGroup.MarginLayoutParams) {
            ViewGroup.MarginLayoutParams p = (ViewGroup.MarginLayoutParams) v.getLayoutParams();
            p.setMargins(l, t, r, b);
            v.requestLayout();
        }
    }

    @Override
    public void setAdapter(ListAdapter adapter) {
        // 不做处理
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();
        selectorPictureAdapter = new SelectorPictureAdapter(new ArrayList<Uri>());
        SelectorPictureGridView.super.setAdapter(selectorPictureAdapter);
        selectorPictureAdapter.addPicture(Uri.EMPTY);
    }

    public void setSelectorPictureListener(View.OnClickListener onClickListener) {
        selectorPictureAdapter.setSelectorPictureListener(onClickListener);
    }

    public void addPicture(Uri uri) {
        selectorPictureAdapter.addPicture(uri);
    }

    public List<Uri> getPictures(){
        return selectorPictureAdapter.getPictures();
    }

    private class SelectorPictureAdapter extends BaseAdapter {

        private final int PICTURE_TYPE = 1;
        private final int SELECTOR_TYPE = 0;

        private final List<Uri> mUriList;
        private OnClickListener onClickListener;

        SelectorPictureAdapter(List<Uri> uriList) {
            this.mUriList = uriList;
        }

        @Override
        public int getItemViewType(int position) {
            if (position == 0) {
                return SELECTOR_TYPE;
            }

            return PICTURE_TYPE;
        }

        @Override
        public int getViewTypeCount() {
            return 2;
        }

        @Override
        public int getCount() {
            return mUriList.size();
        }

        public void addPicture(Uri uri) {
            mUriList.add(uri);
            notifyDataSetChanged();
        }

        public List<Uri> getPictures(){
            return mUriList.subList(1, mUriList.size());
        }

        @Override
        public View getView(final int position, View convertView, ViewGroup parent) {
            int type = getItemViewType(position);
            PictureViewHolder pictureViewHolder = null;
            SelectorViewHolder selectorViewHolder = null;

            if (convertView == null) {
                pictureViewHolder = new PictureViewHolder();
                selectorViewHolder = new SelectorViewHolder();

                switch (type) {
                    case SELECTOR_TYPE:
                        View selectorView = new View(parent.getContext());
                        selectorView.setLayoutParams(new GridView.LayoutParams(getItemSize(),
                                getItemSize()));
                        convertView = selectorView;
                        selectorViewHolder.selectorView = selectorView;
                        convertView.setTag(selectorViewHolder);
                        break;

                    case PICTURE_TYPE:
                        ImageView imageView = new ImageView(parent.getContext());
                        imageView.setLayoutParams(new GridView.LayoutParams(getItemSize(),
                                getItemSize()));
                        imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
                        convertView = imageView;
                        pictureViewHolder.pictureImageView = (ImageView) convertView;
                        convertView.setTag(pictureViewHolder);
                        break;
                }
            } else {
                switch (type) {
                    case SELECTOR_TYPE:
                        selectorViewHolder = (SelectorViewHolder) convertView.getTag();
                        break;
                    case PICTURE_TYPE:
                        pictureViewHolder = (PictureViewHolder) convertView.getTag();
                        break;
                }
            }

            switch (type) {
                case SELECTOR_TYPE:
                    selectorViewHolder.selectorView.setBackgroundColor(Color.BLUE);
                    selectorViewHolder.selectorView.setOnClickListener(onClickListener);
                    break;

                case PICTURE_TYPE:
                    pictureViewHolder.pictureImageView.setImageURI(mUriList.get(position));
                    break;
            }

            return convertView;
        }

        public void setSelectorPictureListener(View.OnClickListener onClickListener) {
            this.onClickListener = onClickListener;
        }

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

        @Override
        public long getItemId(int position) {
            return 0;
        }

        /**
         * 选择照片
         */
        class SelectorViewHolder {
            View selectorView;
        }

        /**
         * 显示的照片
         */
        class PictureViewHolder {
            ImageView pictureImageView;
        }
    }
}