ListView多布局

柔光的暖阳◎ 2022-06-09 06:55 187阅读 0赞

效果图如下：

![Center][]

蓝颜色线圈起来的一块为ListView。

蓝色圈里面的不同颜色分别代表不同布局，一共为4个布局。

其实我们实现起来也很简单，我先简单说下步骤：

1.在布局文件中准备你需要的布局

2.新建一个类继承与BaseAdapter，并重写里面的方法

3.根据布局的多少创建各自的ViewHolder，有3个布局就创建3个ViewHolder

4.在适配器中重写getItemViewType(int position) 和 getViewTypeCount()方法，我简单说下这两个方法getItemViewType方法里面的position是每个item的位置，我们通常来判断这个position的位置来返回具体是哪个布局，但是这里返回结果的时候有一个坑，它是从0开始的如果你直接从1开始就会造成数组越界异常，这里可能说的太笼统不太懂，不要急一步一步的给你介绍，举一个简单的例子，比如你一共有3个布局，在listView中就要在不同的位置显示这3中布局，这时候它return的顺序应该是0,1,2，如果你没有从0开始，直接返回1,2,3的话，一定是会造成数组越界的。然后getViewTypeCount这个方法就是用来返回你布局的总数的。

5.在getView中根据getItemViewType的返回值，进行判断加载不同的布局

废话不多说，直接上代码：

package com.bc.listviewlayouts;
    
    import android.content.Context;
    import android.graphics.Color;
    import android.view.LayoutInflater;
    import android.view.View;
    import android.view.ViewGroup;
    import android.widget.BaseAdapter;
    
    /**
     * 作者：lyh on 2017/8/30 14:41
     * QQ：129929684
     * 邮箱：1299259684@qq.com
     */
    
    public class ListViewAdapter extends BaseAdapter {
    
        private Context mContext;
        private final int TYPE_1 = 0;
        private final int TYPE_2 = 1;
        private final int TYPE_3 = 2;
        private final int TYPE_DEFAULT = 3;
        private final int TYPE_COUNT = 4;
    
        public ListViewAdapter(Context mContext) {
            this.mContext = mContext;
        }
    
        @Override
        public int getCount() {
            return 10;
        }
    
        @Override
        public Object getItem(int i) {
            return "";
        }
    
        @Override
        public long getItemId(int i) {
            return 0;
        }
    
        @Override
        public int getItemViewType(int position) {
            switch (position) {
                case 0:
                    return TYPE_1;
                case 1:
                case 3:
                case 5:
                    return TYPE_2;
                case 2:
                case 4:
                case 8:
                case 9:
                    return TYPE_3;
                default:
                    return TYPE_DEFAULT;
            }
        }
    
        /**
         *
         * @return 一共有几个布局就返回几
         */
        @Override
        public int getViewTypeCount() {
            return TYPE_COUNT;
        }
    
        @Override
        public View getView(int i, View view, ViewGroup viewGroup) {
            ViewHolderOne viewHolderOne = null;
            ViewHolderTwo viewHolderTwo = null;
            ViewHolderThree viewHolderThree = null;
            ViewHolderDefault viewHolderDefault = null;
            int type = getItemViewType(i);//获取返回结果，用来判断加载哪个布局
            if (view == null) {
                LayoutInflater inflater = LayoutInflater.from(mContext);
                switch (type) {
                    case TYPE_1:
                        viewHolderOne = new ViewHolderOne();
                        view = inflater.inflate(R.layout.listview_main_item01, viewGroup, false);
                        viewHolderOne.tv_listView_item01 = view.findViewById(R.id.tv_listView_item01);
                        viewHolderOne.iv_listView_item01 = view.findViewById(R.id.iv_listView_item01);
                        view.setTag(viewHolderOne);
                        break;
                    case TYPE_2:
                        viewHolderTwo = new ViewHolderTwo();
                        view = inflater.inflate(R.layout.listview_main_item02, viewGroup, false);
                        viewHolderTwo.tv_listView_item02 = view.findViewById(R.id.tv_listView_item02);
                        viewHolderTwo.tv2_listView_item02 = view.findViewById(R.id.tv2_listView_item02);
                        view.setTag(viewHolderTwo);
                        break;
                    case TYPE_3:
                        viewHolderThree = new ViewHolderThree();
                        view = inflater.inflate(R.layout.listview_main_item03, viewGroup, false);
                        viewHolderThree.tv_listView_item03 = view.findViewById(R.id.tv_listView_item03);
                        viewHolderThree.iv_listView_item03 = view.findViewById(R.id.iv_listView_item03);
                        viewHolderThree.iv2_listView_item03 = view.findViewById(R.id.iv2_listView_item03);
                        view.setTag(viewHolderThree);
                        break;
                    default:
                        viewHolderDefault = new ViewHolderDefault();
                        view = inflater.inflate(R.layout.listview_main_item_default, viewGroup, false);
                        viewHolderDefault.tv_listView_item_default = view.findViewById(R.id.tv_listView_item_default);
                        view.setTag(viewHolderDefault);
                }
            } else {
                switch (type) { //获取对应的tag
                    case TYPE_1:
                        viewHolderOne = (ViewHolderOne) view.getTag();
                        break;
                    case TYPE_2:
                        viewHolderTwo = (ViewHolderTwo) view.getTag();
                        break;
                    case TYPE_3:
                        viewHolderThree = (ViewHolderThree) view.getTag();
                        break;
                    default:
                        viewHolderDefault = (ViewHolderDefault) view.getTag();
                }
            }
            switch (type) { //装载数据
                case TYPE_1:
                    viewHolderOne.tv_listView_item01.setText("我是第一种布局");
                    viewHolderOne.tv_listView_item01.setTextColor(Color.RED);
                    break;
                case TYPE_2:
                    viewHolderTwo.tv_listView_item02.setText("我是第二种布局的头部");
                    viewHolderTwo.tv_listView_item02.setTextColor(Color.GREEN);
                    viewHolderTwo.tv2_listView_item02.setText("我是第二种布局的尾部");
                    viewHolderTwo.tv2_listView_item02.setTextColor(Color.GREEN);
                    break;
                case TYPE_3:
                    viewHolderThree.tv_listView_item03.setText("我是第三种布局");
                    viewHolderThree.tv_listView_item03.setTextColor(Color.BLUE);
                    break;
                default:
                    viewHolderDefault.tv_listView_item_default.setText("我是默认布局，默认样式");
            }
            return view;
        }
    }

[Center]: /images/20220609/cacf204aee414fe88f456db6a8615803.png