Android 朋友圈之多图显示

先看一下效果图：

MultiImageView：

public class MultiImageView extends LinearLayout {
    public static int MAX_WIDTH = 0;

    // 照片的Url列表
    private List<String> imagesList;

    /**
     * 长度 单位为Pixel *
     */
    private int pxOneMaxWandH;  // 单张图最大允许宽高
    private int pxMoreWandH = 0;// 多张图的宽高
    private int pxImagePadding = LvDPUtil.dip2px(3);// 图片间的间距

    private int MAX_PER_ROW_COUNT = 3;// 每行显示最大数

    private LayoutParams onePicPara;
    private LayoutParams morePara, moreParaColumnFirst;
    private LayoutParams rowPara;

    private OnItemClickListener mOnItemClickListener;

    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        mOnItemClickListener = onItemClickListener;
    }

    public MultiImageView(Context context) {
        super(context);
    }

    public MultiImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    public void setList(List<String> lists) throws IllegalArgumentException {
        if (lists == null) {
            throw new IllegalArgumentException("imageList is null...");
        }
        imagesList = lists;

        if (MAX_WIDTH > 0) {
            // 如果需要两张和四张图横向铺满，这里去掉注释即可。
//            if (lists.size() == 2 || lists.size() == 4) {
//                pxMoreWandH = (MAX_WIDTH - pxImagePadding) / 2;
//            } else {
            pxMoreWandH = (MAX_WIDTH - pxImagePadding * 2) / 3; //解决右侧图片和内容对不齐问题
//            }
            pxOneMaxWandH = MAX_WIDTH * 2 / 3;  // 一张图的时候，图片宽度
            initImageLayoutParams();
        }

        initView();
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        if (MAX_WIDTH == 0) {
            int width = measureWidth(widthMeasureSpec);
            if (width > 0) {
                MAX_WIDTH = width - getPaddingLeft() - getPaddingRight();
                if (imagesList != null && imagesList.size() > 0) {
                    setList(imagesList);
                }
            }
        }
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    /**
     * Determines the width of this view
     *
     * @param measureSpec A measureSpec packed into an int
     * @return The width of the view, honoring constraints from measureSpec
     */
    private int measureWidth(int measureSpec) {
        int result = 0;
        int specMode = MeasureSpec.getMode(measureSpec);
        int specSize = MeasureSpec.getSize(measureSpec);

        if (specMode == MeasureSpec.EXACTLY) {
            // We were told how big to be
            result = specSize;
        } else {
            // Measure the text
            // result = (int) mTextPaint.measureText(mText) + getPaddingLeft()
            // + getPaddingRight();
            if (specMode == MeasureSpec.AT_MOST) {
                // Respect AT_MOST value if that was what is called for by
                // measureSpec
                result = Math.min(result, specSize);
            }
        }
        return result;
    }

    private void initImageLayoutParams() {
        int wrap = LayoutParams.WRAP_CONTENT;
        int match = LayoutParams.MATCH_PARENT;

        onePicPara = new LayoutParams(pxOneMaxWandH, wrap);

        moreParaColumnFirst = new LayoutParams(pxMoreWandH, pxMoreWandH);
        morePara = new LayoutParams(pxMoreWandH, pxMoreWandH);
        morePara.setMargins(pxImagePadding, 0, 0, 0);

        rowPara = new LayoutParams(match, wrap);
    }

    // 根据imageView的数量初始化不同的View布局,还要为每一个View作点击效果
    private void initView() {
        this.setOrientation(VERTICAL);
        this.removeAllViews();
        if (MAX_WIDTH == 0) {
            //为了触发onMeasure()来测量MultiImageView的最大宽度，MultiImageView的宽设置为match_parent
            addView(new View(getContext()));
            return;
        }

        if (imagesList == null || imagesList.size() == 0) {
            return;
        }

        if (imagesList.size() == 1) {
            addView(createImageView(0, false));
        } else {
            int allCount = imagesList.size();
            if (allCount == 4) {
                MAX_PER_ROW_COUNT = 2;
            } else {
                MAX_PER_ROW_COUNT = 3;
            }
            int rowCount = allCount / MAX_PER_ROW_COUNT
                    + (allCount % MAX_PER_ROW_COUNT > 0 ? 1 : 0);// 行数
            for (int rowCursor = 0; rowCursor < rowCount; rowCursor++) {
                LinearLayout rowLayout = new LinearLayout(getContext());
                rowLayout.setOrientation(LinearLayout.HORIZONTAL);

                rowLayout.setLayoutParams(rowPara);
                if (rowCursor != 0) {
                    rowLayout.setPadding(0, pxImagePadding, 0, 0);
                }

                int columnCount = allCount % MAX_PER_ROW_COUNT == 0 ? MAX_PER_ROW_COUNT
                        : allCount % MAX_PER_ROW_COUNT;//每行的列数
                if (rowCursor != rowCount - 1) {
                    columnCount = MAX_PER_ROW_COUNT;
                }
                addView(rowLayout);

                int rowOffset = rowCursor * MAX_PER_ROW_COUNT;// 行偏移
                for (int columnCursor = 0; columnCursor < columnCount; columnCursor++) {
                    int position = columnCursor + rowOffset;
                    rowLayout.addView(createImageView(position, true));
                }
            }
        }
    }

    private ImageView createImageView(final int position, final boolean isMultiImage) {
        String url = "";
        if (!TextUtils.isEmpty(imagesList.get(position))) {
            url = imagesList.get(position);
        }

        ImageView imageView = new ColorFilterImageView(getContext());
        if (isMultiImage) {
            imageView.setScaleType(ScaleType.CENTER_CROP);
            imageView.setLayoutParams(position % MAX_PER_ROW_COUNT == 0 ? moreParaColumnFirst : morePara);
        } else {
            imageView.setAdjustViewBounds(true);
            imageView.setScaleType(ScaleType.FIT_START);
            imageView.setMaxHeight(pxOneMaxWandH);
            imageView.setLayoutParams(onePicPara);
        }

        imageView.setId(url.hashCode());
        imageView.setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                if (mOnItemClickListener != null) {
                    mOnItemClickListener.onItemClick(v, position);
                }
            }
        });
        // 加载网络图片/设置图片显示
        Glide.with(getContext()).load(url).into(imageView);
        return imageView;
    }

    public interface OnItemClickListener {
       void onItemClick(View view, int position);
    }
}

点击有阴影的 ImageView :

public class ColorFilterImageView extends ImageView implements OnTouchListener {
    public ColorFilterImageView(Context context) {
        this(context, null, 0);
    }

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

    public ColorFilterImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
        init();
    }

    private void init() {
        setOnTouchListener(this);
    }

    @Override
    public boolean onTouch(View v, MotionEvent event) {
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:  // 按下时图像变灰
                setColorFilter(Color.GRAY, Mode.MULTIPLY);
                break;
            case MotionEvent.ACTION_UP:   // 手指离开或取消操作时恢复原色
            case MotionEvent.ACTION_CANCEL:
                setColorFilter(Color.TRANSPARENT);
                break;
            default:
                break;
        }
        return false;
    }
}

用法

<com.lvfq.myworkingtest.dynamic.view.MultiImageView
        android:id="@+id/multi_image"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:padding="@dimen/dp_10" />

MultiImageView multiImageView = findViewById(R.id.multi_image);
multiImageView.setList(imgs);   // List<String> 类型的图片地址列表
multiImage.setOnItemClickListener(new MultiImageView.OnItemClickListener() {
                    @Override
                    public void onItemClick(View view, int position) {
                       // To do something or 查看大图.
                    }
                });

后续在单独整理一下点赞，评论回复的代码。

附：如果需要完整朋友圈项目的话，这里推荐一个 Github 项目 仿微信实现的朋友圈