Android新手开发之旅-选择标签实现点击选中再次点击取消

liu

先看下要实现的效果：


        


思路就是写一个数据用来存放每个item的状态(例如初始状态设置为0，点击后设置为1)，点击时通过item的状态来判断是否该选中还是取消




示例代码：

activity_main.xml：

[XML] 纯文本查看 复制代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <GridView
        android:id="@+id/gv"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:horizontalSpacing="15dp"
        android:verticalSpacing="15dp"
        android:numColumns="3" />

</LinearLayout>

item布局
item_gridview.xml:

[XML] 纯文本查看 复制代码

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
<TextView
    android:id="@+id/tv"
    android:layout_width="match_parent"
    android:layout_height="50dp"
    android:gravity="center"
    android:textColor="@android:color/black"/>
</LinearLayout>

MainActivity

[Java] 纯文本查看 复制代码

package com.company.helloworld.firstapplication;

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.GridView;

import java.util.ArrayList;
import java.util.List;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        initView();
    }

    private void initView() {
        List<Integer> list = new ArrayList<>();
        for (int i = 0; i < 10; i++) {
            list.add(i);
        }
        GridView gridView = (GridView) findViewById(R.id.gv);
        MyAdapter adapter = new MyAdapter(this, list);
        gridView.setAdapter(adapter);
    }

}

MyAdapter

[Java] 纯文本查看 复制代码

package com.company.helloworld.firstapplication;

import android.content.Context;
import android.graphics.Color;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.TextView;

import java.util.List;

/**
 * Created by Administrator on 2018/12/17.
 */

public class MyAdapter extends BaseAdapter {
    private Context context;
    private List<Integer> list;
    //这个数组用来存放item的点击状态
    private int[] statue;

    public MyAdapter(Context context, List<Integer> list) {
        this.context = context;
        this.list = list;
        statue = new int[list.size()];
        for (int i = 0; i < list.size(); i++) {
            statue[i] = 0;      //初始化item点击状态的数组  0:未选中  1：选中
        }
    }

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

    @Override
    public Object getItem(int i) {
        return list.get(i);
    }

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

    @Override
    public View getView(final int i, View view, ViewGroup viewGroup) {
        final ViewHolder holder;
        if (view == null) {
            holder = new ViewHolder();
            view = LayoutInflater.from(context).inflate(R.layout.item_gridview, null);
            holder.tv = view.findViewById(R.id.tv);
            view.setTag(holder);
        } else {
            holder = (ViewHolder) view.getTag();
        }
        holder.tv.setText(String.valueOf(list.get(i)));
        holder.tv.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if (statue[i] == 0) {
                    holder.tv.setBackgroundColor(Color.BLUE);
                    holder.tv.setTextColor(Color.WHITE);
                    //设置为选中状态
                    statue[i] = 1;
                } else {
                    holder.tv.setBackgroundColor(Color.WHITE);
                    holder.tv.setTextColor(Color.BLACK);
                    //设置为未选中状态
                    statue[i] = 0;
                }
            }
        });
        return view;
    }

    class ViewHolder {
        private TextView tv;
    }
}

站长苏飞

我只是路过打酱油的。

Amy

真是难得给力的帖子啊。