Android实现今日头条订阅频道效果

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
tools:context="com.example.a2_.MainActivity">

<TextView
  android:background="@android:color/holo_blue_dark"
  android:gravity="center_horizontal"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:text="已订阅频道" />

<com.example.a2_.MyGridLayout
  android:id="@+id/gl1"
  android:columnCount="4"
  android:layout_gravity="center_horizontal"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">
</com.example.a2_.MyGridLayout>

<TextView
  android:gravity="center_horizontal"
  android:background="@android:color/darker_gray"
  android:layout_width="match_parent"
  android:layout_height="wrap_content"
  android:text="未订阅频道" />

<com.example.a2_.MyGridLayout
  android:columnCount="4"
  android:id="@+id/gl2"
  android:layout_gravity="center_horizontal"
  android:layout_width="wrap_content"
  android:layout_height="wrap_content">
</com.example.a2_.MyGridLayout>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<corners android:radius="5dp"/>
<stroke android:color="#000"
  android:width="1dp"/>
</shape>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android">
<corners android:radius="5dp"/>
<stroke android:color="#ff0000"
  android:dashGap="1dp"
  android:dashWidth="3dp"
  android:width="1dp"/>
</shape>

package com.example.a2_;

import android.animation.LayoutTransition;
import android.content.Context;
import android.graphics.Color;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.DragEvent;
import android.view.View;
import android.widget.GridLayout;
import android.widget.TextView;

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

/**
 * Created by Administrator on 2017.06.08.0008.
 */

public class MyGridLayout extends GridLayout implements View.OnDragListener {

private OnItemClickListener listener;
private List<Rect> rects;
private View DragItem = null;
private boolean dragable;

public MyGridLayout(Context context, AttributeSet attrs) {
  super(context, attrs);
  //添加动画
  setLayoutTransition(new LayoutTransition());
  //舰艇拖拽事件
  setOnDragListener(this);
}

//根据传递进来的数据,动态地添加控件
public void setData(List<String> list) {
  for (int i = 0; i < list.size(); i++) {
    addItem(list.get(i));
  }
}

public void addItem(String s) {
  final TextView textView = new TextView(getContext());
  textView.setText(s);
  textView.setTextColor(Color.BLACK);
  textView.setPadding(15, 5, 15, 5);
  //设置背景
  textView.setBackgroundResource(R.drawable.selector_item_bg);
  textView.setTextSize(25);
  //将控件添加到页面中
  addView(textView);

  LayoutParams layoutParams = (LayoutParams) textView.getLayoutParams();
  //设置外边距
  layoutParams.setMargins(5, 5, 5, 5);

  //监听textview点击事件
  textView.setOnClickListener(new OnClickListener() {
    @Override
    public void onClick(View v) {

      if (listener != null) {
        listener.onItemClick(v);
      }
    }
  });

  //监听控件的长按事件
  textView.setOnLongClickListener(new OnLongClickListener() {

    @Override
    public boolean onLongClick(View v) {

      if (!dragable) {
        return true;
      }
      //把当前长按的控件变红,并且有虚线
      v.setBackgroundResource(R.drawable.selector_item_red_bg);
      //开始拖拽控件
      v.startDrag(null, new DragShadowBuilder(v), null, 0);
      DragItem = v;
      //获取所有空间的矩形区域
      getAllRect();

      return true;
    }
  });
}

//获取所有的矩形区域
private void getAllRect() {
  rects = new ArrayList<>();
  for (int i = 0; i < getChildCount(); i++) {
    View view = getChildAt(i);
    //获取每个控件的坐标点,并存在集合中
    rects.add(new Rect(view.getLeft(), view.getTop(), view.getRight(), view.getBottom()));
  }
}

public void setOnClickListener(OnItemClickListener listener) {
  this.listener = listener;
}

@Override
public boolean onDrag(View v, DragEvent event) {

  if (!dragable) {
    return true;
  }

  switch (event.getAction()) {
    case DragEvent.ACTION_DRAG_STARTED:
      System.out.println("ACTION_DRAG_STARTED");
      break;
    case DragEvent.ACTION_DRAG_ENTERED:
      System.out.println("ACTION_DRAG_ENTERED");
      break;
    case DragEvent.ACTION_DRAG_EXITED:
      System.out.println("ACTION_DRAG_EXITED");
      break;
    case DragEvent.ACTION_DRAG_LOCATION:
      System.out.println("ACTION_DRAG_LOCATION");
      //拖拽移动时,位置发生变化
      //根据当前的位置,判断应该插入到哪个位置
      int dragItemIndex = findDragItem(event);
      if (dragItemIndex != -1 && DragItem != null && getChildAt(dragItemIndex) != DragItem) {
        //先删除原来的控件
        removeView(DragItem);
        //吧新的控件拖拽到新的位置
        addView(DragItem, dragItemIndex);

      }
      break;
    case DragEvent.ACTION_DROP:
      System.out.println("ACTION_DROP");
      break;
    case DragEvent.ACTION_DRAG_ENDED:
      System.out.println("ACTION_DRAG_ENDED");

      if (DragItem != null) {
        DragItem.setBackgroundResource(R.drawable.selector_item_bg);
      }
      break;
  }
  return true;
}

private int findDragItem(DragEvent event) {
  if (rects == null) {
    return -1;
  }
  for (int i = 0; i < rects.size(); i++) {
    //如果鼠标当前的坐标包含在某个控件的坐标内部,那就说明,当前在该空间内部
    if (rects.get(i).contains((int) event.getX(), (int) event.getY())) {
      return i;
    }
  }
  return -1;
}

public interface OnItemClickListener {
  void onItemClick(View v);
}

// 设置控件是否可以拖拽
public void setDragable(boolean dragable) {
  this.dragable = dragable;
}
}

package com.example.a2_;

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.LinearLayout;
import android.widget.TextView;

import java.util.Arrays;
import java.util.List;

import butterknife.ButterKnife;
import butterknife.InjectView;

public class MainActivity extends Activity {


@InjectView(R.id.gl1)
MyGridLayout gl1;
@InjectView(R.id.gl2)
MyGridLayout gl2;
@InjectView(R.id.activity_main)
LinearLayout activityMain;
//创建已订阅和为订阅的集合
private List<String> select = Arrays.asList("北京", "中国", "国际", "体育", "生活", "旅游", "科技", "军事", "时尚", "财经", "育儿", "汽车");
private List<String> unselect = Arrays.asList("娱乐", "服饰", "音乐", "视频", "段子", "搞笑", "科学", "房产", "名站");

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

  //初始化数据
  initData();
}


private void initData() {

  gl1.setData(select);
  gl2.setData(unselect);

  gl1.setDragable(true);

  //设置监听
  gl1.setOnClickListener(new MyGridLayout.OnItemClickListener() {
    @Override
    public void onItemClick(View v) {
      gl1.removeView(v);
      //设置中间人
      String s = ((TextView) v).getText().toString();
      gl2.addItem(s);
    }
  });

  gl2.setOnClickListener(new MyGridLayout.OnItemClickListener() {
    @Override
    public void onItemClick(View v) {
      gl2.removeView(v);
      //设置中间人
      String s = ((TextView) v).getText().toString();
      gl1.addItem(s);
    }
  });
}

}