Android 自定义GridLayout实现频道管理

前言

以前总是在CSDN上看各位前辈的精彩博客，从中也学习了很多东西。其实自己也一直想写博客，直到今天终于要踏出这一步了，有点小兴奋，哈哈！不足之处，还请各位同仁不吝赐教，拜谢！！！

话不多说，工作中我们时常会遇到频道管理的需求，不少博客使用GridView实现这一功能，个人喜欢用自定义的GridLayout实现，萝卜白菜各有所爱，嘿嘿。

功能

要实现的功能如上图所示（当然，左边只是一个参考，这里界面不是重点，我们要实现这个功能）

1.   分上下两部分

2.“我的频道”实现了长按拖拽排序功能；同时，点击某一子条目时，将该条目从“我的频道”中删除，添加到“更多频道”中。

3.“更多频道”实现了点击事件，当点击某一子条目时，该子条目从“更多频道”中删除，添加到“我的频道”中。

实现代码

主程序代码：

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;import java.util.ArrayList;
import java.util.List;public class MainActivity extends AppCompatActivity {private DragGridLayout showGridLayout;private DragGridLayout hideGridLayout;@Overrideprotected void onCreate(Bundle savedInstanceState) {super.onCreate(savedInstanceState);setContentView(R.layout.activity_main);initCustom();}private void initCustom() {showGridLayout = (DragGridLayout) findViewById(R.id.dgl_main_show);showGridLayout.setResource(R.drawable.selector_textbg, 10, 5);showGridLayout.setEnableDrag(true);List<String> items = new ArrayList<>();items.add("推荐");items.add("本地事");items.add("本地人");items.add("社区");items.add("图集");items.add("要闻");items.add("热点");items.add("旅游");items.add("健康");showGridLayout.setItems(items);hideGridLayout = (DragGridLayout) findViewById(R.id.dgl_main_bottom);hideGridLayout.setEnableDrag(false);hideGridLayout.setResource(R.drawable.selector_textbg, 10, 5);List<String> items1 = new ArrayList<>();items1.add("家居");items1.add("奇石");items1.add("螺蛳粉");items1.add("情感");items1.add("文化");items1.add("体育");items1.add("汽车");items1.add("本地号");items1.add("爆料");items1.add("时政");items1.add("美女");items1.add("公益");items1.add("公民榜样");items1.add("亲子");items1.add("社会");items1.add("舌尖柳州");items1.add("开心一刻");items1.add("居柳州");hideGridLayout.setItems(items1);//设置点击事件showGridLayout.setOnItemClickListener(new DragGridLayout.OnItemClickListener() {@Overridepublic void onItemClick(TextView tv) {//当点击时，将返回的TextView从showGridLayout容器中删除，在添加到hideGridLayout中showGridLayout.removeView(tv);hideGridLayout.addItem(tv.getText().toString());}});hideGridLayout.setOnItemClickListener(new DragGridLayout.OnItemClickListener() {@Overridepublic void onItemClick(TextView tv) {hideGridLayout.removeView(tv);showGridLayout.addItem(tv.getText().toString());}});}}

布局：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"xmlns:tools="http://schemas.android.com/tools"android:layout_width="match_parent"android:layout_height="match_parent"android:orientation="vertical"><LinearLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"android:orientation="vertical"><TextViewandroid:layout_width="match_parent"android:layout_height="wrap_content"android:background="@color/colorPry"android:text="点击增删频道，长按拖拽排序"/><com.example.customview.DragGridLayoutandroid:id="@+id/dgl_main_show"android:layout_width="match_parent"android:layout_height="wrap_content"></com.example.customview.DragGridLayout></LinearLayout><LinearLayoutandroid:layout_width="match_parent"android:layout_height="wrap_content"android:orientation="vertical"><TextViewandroid:layout_width="match_parent"android:layout_height="wrap_content"android:background="@color/colorPry"android:text="频道管理"/><com.example.customview.DragGridLayoutandroid:id="@+id/dgl_main_bottom"android:layout_width="match_parent"android:layout_height="wrap_content"></com.example.customview.DragGridLayout></LinearLayout></LinearLayout>

注释比较详细了，直接上代码，其中的一些参数，例如margin和padding，可根据项目需求，具体定制。

import android.animation.LayoutTransition;
import android.content.Context;
import android.graphics.Rect;
import android.util.AttributeSet;
import android.view.DragEvent;
import android.view.Gravity;
import android.view.View;
import android.widget.GridLayout;
import android.widget.TextView;import java.util.List;/*** Created by ZLM on 2017/4/3.*/public class DragGridLayout extends GridLayout {private boolean ableDrag;private Rect[] rects;private View dragView;private OnItemClickListener itemClickListener;//拖拽监听private View.OnDragListener odl = new View.OnDragListener() {@Overridepublic boolean onDrag(View view, DragEvent dragEvent) {switch (dragEvent.getAction()) {case DragEvent.ACTION_DRAG_STARTED://当拖拽事件产生时，给每个子控件创建出对应的矩形initRects();break;case DragEvent.ACTION_DRAG_LOCATION://当手指移动时，判断当前进入了哪一个子控件范围内，并返回对应子控件的索引int touchIndex = getTouchIndex(dragEvent);if (touchIndex > -1 && dragView != null && dragView != DragGridLayout.this.getChildAt(touchIndex)) {//先把拖拽的view从当前位置删除，再添加到touchIndex上DragGridLayout.this.removeView(dragView);DragGridLayout.this.addView(dragView, touchIndex);}break;case DragEvent.ACTION_DRAG_ENDED:if (dragView != null) {dragView.setEnabled(true);}break;default:break;}return true;}};//长按监听private View.OnLongClickListener olcl = new View.OnLongClickListener() {@Overridepublic boolean onLongClick(View view) {//长按事件发生时，即给dragView赋值dragView = view;//拖拽事件view.startDrag(null, new View.DragShadowBuilder(view), null, 0);view.setEnabled(false);return false;}};private int getTouchIndex(DragEvent dragEvent) {for (int i = 0; i < rects.length; i++) {Rect rect = rects[i];if (rect.contains((int) dragEvent.getX(), (int) dragEvent.getY())) {return i;}}return -1;}//创建子控件对应的矩形private void initRects() {//给容器中的每一个子控件都新建一个矩形rects = new Rect[getChildCount()];for (int i = 0; i < getChildCount(); i++) {View childAt = getChildAt(i);rects[i] = new Rect(childAt.getLeft(), childAt.getTop(), childAt.getRight(), childAt.getBottom());}}public DragGridLayout(Context context) {this(context, null);}public DragGridLayout(Context context, AttributeSet attrs) {super(context, attrs);setColumnCount(4);setLayoutTransition(new LayoutTransition());}//定义方法，由外部传递一个栏目的数据集合进来，在这里根据数据集合动态创建表格界面public void setItems(List<String> items) {for (String item : items) {addItem(item);}}//定义方法，设置是否允许拖拽public void setEnableDrag(boolean EnableDrag) {ableDrag = EnableDrag;if (ableDrag) {setOnDragListener(odl);} else {setOnDragListener(null);}}//定义接口回调public interface OnItemClickListener {public void onItemClick(TextView tv);}public void setOnItemClickListener(OnItemClickListener listener) {this.itemClickListener = listener;}public void addItem(String item) {TextView tv = getNewTextView();tv.setText(item);this.addView(tv);}//定义方法，外部传入子条目的背景资源Id,外边距margin（px）,tv内边距padding（px）private final float scale = getContext().getResources().getDisplayMetrics().density;private int resId;private int margin;private int padding;public void setResource(int ResourceId, int margin, int padding) {this.resId = ResourceId;this.margin = (int) (margin * scale + 0.5f);this.padding = (int) (padding * scale + 0.5f);}public TextView getNewTextView() {GridLayout.LayoutParams layoutParams = new GridLayout.LayoutParams();layoutParams.width = getResources().getDisplayMetrics().widthPixels / 4 - 2 * margin;layoutParams.height = GridLayout.LayoutParams.WRAP_CONTENT;layoutParams.setMargins(margin, margin, margin, margin);TextView tv = new TextView(getContext());tv.setLayoutParams(layoutParams);tv.setGravity(Gravity.CENTER);tv.setBackgroundResource(resId);tv.setPadding(padding, padding, padding, padding);if (ableDrag) {tv.setOnLongClickListener(olcl);} else {tv.setOnLongClickListener(null);}tv.setOnClickListener(new OnClickListener() {@Overridepublic void onClick(View view) {if (itemClickListener != null) {itemClickListener.onItemClick((TextView) view);}}});return tv;}
}

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android"><item android:state_enabled="true" android:drawable="@drawable/shape_textbg_nomal"/><item android:state_enabled="false" android:drawable="@drawable/shape_textbg_pressed"/></selector>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"><stroke android:width="1dp" android:color="@color/colorBlack"/><corners android:radius="@dimen/dp8"/><solid android:color="@color/colorWhite"/>
</shape>

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"><stroke android:width="1dp"android:dashWidth="2dp"android:dashGap="3dp"android:color="@color/colorRed"/><corners android:radius="@dimen/dp8"/><solid android:color="@color/colorWhite"/>
</shape>