开源项目之瀑布流DodoWaterFall
DodoWaterFall实现了类似于迷尚android和蘑菇街android的瀑布流布局。
项目如图：
效果如图：
项目总共五个目标文件！~
LazyScrollView类：可以上下滚动的视图。
MainActivity类：主界面类。
FlowTag类：图片信息标识。
FlowView类：图片视图 ，可以使用线程加载图片或ImageLoaderTask加载图片。
ImageLoaderTask类：同步任务方式加载图片。
主要成员：
//初始化布局 把循环加入图片，然后加入到容器、最后加入到容器队列private void InitLayout(){waterfall_scroll = (LazyScrollView) findViewById(R.id.waterfall_scroll);waterfall_scroll.getView();waterfall_scroll.setOnScrollListener(new OnScrollListener(){@Overridepublic void onTop(){// 滚动到最顶端Log.d("LazyScroll", "Scroll to top");}@Overridepublic void onScroll(){}@Overridepublic void onBottom(){// 滚动到最低端AddItemToContainer(++current_page, page_count);}@Overridepublic void onAutoScroll(int l, int t, int oldl, int oldt){// Log.d("MainActivity",// String.format("%d %d %d %d", l, t, oldl, oldt));// Log.d("MainActivity", "range:" + range);// Log.d("MainActivity", "range-t:" + (range - t));scroll_height = waterfall_scroll.getMeasuredHeight();Log.d("MainActivity", "scroll_height:" + scroll_height);if (t > oldt){// 向下滚动if (t > 2 * scroll_height){// 超过两屏幕后for (int k = 0; k < column_count; k++){LinearLayout localLinearLayout = waterfall_items.get(k);if (pin_mark[k].get(Math.min(bottomIndex[k] + 1,lineIndex[k])) <= t + 3 * scroll_height){// 最底部的图片位置小于当前t+3*屏幕高度((FlowView) waterfall_items.get(k).getChildAt(Math.min(1 + bottomIndex[k],lineIndex[k]))).Reload();bottomIndex[k] = Math.min(1 + bottomIndex[k],lineIndex[k]);}Log.d("MainActivity","headIndex:" + topIndex[k] + " footIndex:"+ bottomIndex[k] + " headHeight:"+ pin_mark[k].get(topIndex[k]));if (pin_mark[k].get(topIndex[k]) < t - 2* scroll_height){// 未回收图片的最高位置<t-两倍屏幕高度int i1 = topIndex[k];topIndex[k]++;((FlowView) localLinearLayout.getChildAt(i1)).recycle();Log.d("MainActivity", "recycle,k:" + k+ " headindex:" + topIndex[k]);}}}} else{// 向上滚动if (t > 2 * scroll_height){// 超过两屏幕后for (int k = 0; k < column_count; k++){LinearLayout localLinearLayout = waterfall_items.get(k);if (pin_mark[k].get(bottomIndex[k]) > t + 3* scroll_height){((FlowView) localLinearLayout.getChildAt(bottomIndex[k])).recycle();bottomIndex[k]--;}if (pin_mark[k].get(Math.max(topIndex[k] - 1, 0)) >= t- 2 * scroll_height){((FlowView) localLinearLayout.getChildAt(Math.max(-1 + topIndex[k], 0))).Reload();topIndex[k] = Math.max(topIndex[k] - 1, 0);}}}}}});waterfall_container = (LinearLayout) this.findViewById(R.id.waterfall_container);handler = new Handler(){@Overridepublic void dispatchMessage(Message msg){super.dispatchMessage(msg);}@Overridepublic void handleMessage(Message msg){// super.handleMessage(msg);switch (msg.what){case 1:FlowView v = (FlowView) msg.obj;int w = msg.arg1;int h = msg.arg2;// Log.d("MainActivity",// String.format(// "获取实际View高度:%d,ID：%d,columnIndex:%d,rowIndex:%d,filename:%s",// v.getHeight(), v.getId(), v// .getColumnIndex(), v.getRowIndex(),// v.getFlowTag().getFileName()));String f = v.getFlowTag().getFileName();// 此处计算列值int columnIndex = GetMinValue(column_height);v.setColumnIndex(columnIndex);column_height[columnIndex] += h;pins.put(v.getId(), f);iviews.put(v.getId(), v);waterfall_items.get(columnIndex).addView(v);lineIndex[columnIndex]++;pin_mark[columnIndex].put(lineIndex[columnIndex],column_height[columnIndex]);bottomIndex[columnIndex] = lineIndex[columnIndex];break;}}@Overridepublic boolean sendMessageAtTime(Message msg, long uptimeMillis){return super.sendMessageAtTime(msg, uptimeMillis);}};//容器选项waterfall_items = new ArrayList<LinearLayout>();for (int i = 0; i < column_count; i++){LinearLayout itemLayout = new LinearLayout(this);LinearLayout.LayoutParams itemParam = new LinearLayout.LayoutParams(item_width, LayoutParams.WRAP_CONTENT);itemLayout.setPadding(2, 2, 2, 2);itemLayout.setOrientation(LinearLayout.VERTICAL);itemLayout.setLayoutParams(itemParam);waterfall_items.add(itemLayout);waterfall_container.addView(itemLayout);}// 加载所有图片路径try{image_filenames = Arrays.asList(asset_manager.list(image_path));} catch (IOException e){e.printStackTrace();}// 第一次加载AddItemToContainer(current_page, page_count);}//把单一项加入到容器private void AddItemToContainer(int pageindex, int pagecount){int currentIndex = pageindex * pagecount;int imagecount = 10000;// image_filenames.size();for (int i = currentIndex; i < pagecount * (pageindex + 1)&& i < imagecount; i++){loaded_count++;Random rand = new Random();int r = rand.nextInt(image_filenames.size());AddImage(image_filenames.get(r),(int) Math.ceil(loaded_count / (double) column_count),loaded_count);}}//加入图片private void AddImage(String filename, int rowIndex, int id){FlowView item = new FlowView(context);// item.setColumnIndex(columnIndex);item.setRowIndex(rowIndex);item.setId(id);item.setViewHandler(this.handler);// 多线程参数FlowTag param = new FlowTag();param.setFlowId(id);param.setAssetManager(asset_manager);param.setFileName(image_path + "/" + filename);param.setItemWidth(item_width);item.setFlowTag(param);item.LoadImage();// waterfall_items.get(columnIndex).addView(item);}学习的目标是成熟！~~