android 小例之两列菜单关联

Posted 2020-06-24

因为项目需要，做了个简单的菜单关联，其实很简单 左侧是个listview 选中的时候刷新右侧关联数据，类似网易新闻选择订阅页面

这里需要注意的是 在点击完左侧菜单列表的时候 直接右侧刷新会不一定出来数据，这个时候 将刷新放到adapter里面处理就可以了

废话不说 直接代码，代码里面有详细备注

// 总数据来源 选中颜色 左右列表适配器
	List<TwoListData> twoListDatas = new ArrayList<TwoListData>();
	private ColorStateList red;
	private ColorStateList black;
	private MyAdapter leftMyAdapter;
	private MyAdapter rightMyAdapter;

	// 左侧和右侧关联数据
	List<String> leftString = new ArrayList<String>();
	List<String> rightString = new ArrayList<String>();
	// 右侧列表
	private ListView lv_right;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		// TODO Auto-generated method stub
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_two_list);
		Resources resource = (Resources) getResources();
		red = (ColorStateList) resource.getColorStateList(R.color.color_ff0000);
		black = (ColorStateList) resource
				.getColorStateList(R.color.color_000000);

		ListView lv_left = (ListView) this.findViewById(R.id.lv_regison);
		lv_right = (ListView) this.findViewById(R.id.lv_block);
		for (int i = 0; i < 10; i++) {
			twoListDatas.add(new TwoListData("left" + i));
		}
		leftString = getLeftData();
		rightString = twoListDatas.get(0).getRightDataList();
		leftMyAdapter = new MyAdapter(getLeftData());
		rightMyAdapter = new MyAdapter(rightString);
		lv_left.setAdapter(leftMyAdapter);
		lv_right.setAdapter(rightMyAdapter);

		// 左侧列表选中时候 及时刷新右侧列表关联数据
		lv_left.setOnItemClickListener(new OnItemClickListener() {
			@Override
			public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
					long arg3) {
				leftMyAdapter.setSelected(arg2);
				rightString = twoListDatas.get(arg2).getRightDataList();
				rightMyAdapter.setMydata(rightString);
			}
		});

		// 右侧列表选中 显示对应关联数据
		lv_right.setOnItemClickListener(new OnItemClickListener() {

			@Override
			public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
					long arg3) {
				rightMyAdapter.setSelected(arg2);
				Toast.makeText(
						TwoListActivity.this,
						"选中了左边第" + leftMyAdapter.selectedPos + "位置   右侧的第" + arg2+"位置",
						Toast.LENGTH_LONG).show();
			}
		});

	}

	/**
	 * 获取左侧数据
	 * 
	 * @return
	 */
	public List<String> getLeftData() {
		List<String> leftDataList = new ArrayList<String>();
		for (TwoListData mTwoListData : twoListDatas) {
			leftDataList.add(mTwoListData.getName());
		}
		return leftDataList;
	}

	/**
	 * 适配器
	 * 
	 * @author zxc
	 * 
	 */
	public class MyAdapter extends BaseAdapter {
		int selectedPos = 0;// 标识选中
		public List<String> getMydata() {
			return mydata;
		}
		public void setMydata(List<String> mydata) {
			this.mydata = mydata;
			notifyDataSetChanged();
		}

		private List<String> mydata;

		public MyAdapter(List<String> mydata) {
			this.mydata = mydata;
		}

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

		@Override
		public Object getItem(int position) {
			// TODO Auto-generated method stub
			return mydata.get(position);
		}

		@Override
		public long getItemId(int position) {
			// TODO Auto-generated method stub
			return position;
		}

		@Override
		public View getView(int position, View convertView, ViewGroup parent) {
			ViewHolder holder;
			if (convertView == null) {
				holder = new ViewHolder();
				convertView = LayoutInflater.from(TwoListActivity.this)
						.inflate(R.layout.adp_two_list, null);
				holder.iv_title = (TextView) convertView
						.findViewById(R.id.adptv_title);
				convertView.setTag(holder);
			} else {
				holder = (ViewHolder) convertView.getTag();
			}
			holder.iv_title.setText(mydata.get(position));
			if (selectedPos == position) {
				holder.iv_title.setTextColor(red);
			} else {
				holder.iv_title.setTextColor(black);
			}
			return convertView;
		}

		private class ViewHolder {
			private TextView iv_title;
		}

		/**
		 * 标识选中并刷新
		 * 
		 * @param po
		 */
		public void setSelected(int po) {
			selectedPos = po;
			notifyDataSetChanged();
		}
	}

　　数据模型如下

public class TwoListData {
	private String name;// 标注
	private List<String> rightDataList;
	public TwoListData(String name) {
		this.name = name;
		setRightData(name, new Random().nextInt(15) + 1);// 随机1到15
	}

	/**
	 * 根据标注 添加右侧关联数据
	 * 
	 * @param name
	 * @param num
	 */
	public void setRightData(String name, int num) {
		List<String> rightDataList = new ArrayList<String>();
		for (int i = 0; i < num; i++) {
			rightDataList.add(name + i);
		}
		setRightDataList(rightDataList);
	}
	
	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public List<String> getRightDataList() {
		return rightDataList;
	}
	public void setRightDataList(List<String> rightDataList) {
		this.rightDataList = rightDataList;
	}
	
}

　　

效果