本节引言:
本节给大家介绍的是第二个Adapter类的控件——GridView(网格视图),见名知义,ListView是列表, GridView就是显示网格!他和ListView一样是AbsListView的子类!很多东西和ListView都是相通的, 本节我们就来学习他的基本用法~
1.相关属性:
下面是GridView中的一些属性:
- android:columnWidth:设置列的宽度
- android:gravity:组件对其方式
- android:horizontalSpacing:水平方向每个单元格的间距
- android:verticalSpacing:垂直方向每个单元格的间距
- android:numColumns:设置列数
- android:stretchMode:设置拉伸模式,可选值如下: none:不拉伸;spacingWidth:拉伸元素间的间隔空隙 columnWidth:仅仅拉伸表格元素自身 spacingWidthUniform:既拉元素间距又拉伸他们之间的间隔空袭
2.使用示例:
下面通过一个简单的例子来熟悉这个控件的使用: (这里用的Adapter我们直接用之2.5.0中教大家写的可复用的BaseAdapter~)
实现的效果图:
代码实现:
首先是GridView 的 Item的布局:item_grid_icon.xml:
<?xml version="1.0" encoding="utf-8"?> <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" android:padding="5dp"> <ImageView android:id="@+id/img_icon" android:layout_width="64dp" android:layout_height="64dp" android:layout_centerInParent="true" android:src="@mipmap/iv_icon_1" /> <TextView android:id="@+id/txt_icon" android:layout_width="wrap_content" android:layout_height="wrap_content" android:layout_below="@id/img_icon" android:layout_centerHorizontal="true" android:layout_marginTop="30dp" android:text="呵呵" android:textSize="18sp" /> </RelativeLayout>
接着我们写个entity实体类:Icon.java:
/** * Created by Jay on 2015/9/24 0024. */ public class Icon { private int iId; private String iName; public Icon() { } public Icon(int iId, String iName) { this.iId = iId; this.iName = iName; } public int getiId() { return iId; } public String getiName() { return iName; } public void setiId(int iId) { this.iId = iId; } public void setiName(String iName) { this.iName = iName; } }
最后是MainActivity的布局以及Java代码
activity_main.xml:
<RelativeLayout xmlns: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:padding="5dp" tools:context=".MainActivity"> <!--numColumns设置每行显示多少个--> <GridView android:id="@+id/grid_photo" android:layout_width="match_parent" android:layout_height="match_parent" android:numColumns="3" /> </RelativeLayout>
MainActivity.java:
public class MainActivity extends AppCompatActivity { private Context mContext; private GridView grid_photo; private BaseAdapter mAdapter = null; private ArrayList<Icon> mData = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); mContext = MainActivity.this; grid_photo = (GridView) findViewById(R.id.grid_photo); mData = new ArrayList<Icon>(); mData.add(new Icon(R.mipmap.iv_icon_1, "图标1")); mData.add(new Icon(R.mipmap.iv_icon_2, "图标2")); mData.add(new Icon(R.mipmap.iv_icon_3, "图标3")); mData.add(new Icon(R.mipmap.iv_icon_4, "图标4")); mData.add(new Icon(R.mipmap.iv_icon_5, "图标5")); mData.add(new Icon(R.mipmap.iv_icon_6, "图标6")); mData.add(new Icon(R.mipmap.iv_icon_7, "图标7")); mAdapter = new MyAdapter<Icon>(mData, R.layout.item_grid_icon) { @Override public void bindView(ViewHolder holder, Icon obj) { holder.setImageResource(R.id.img_icon, obj.getiId()); holder.setText(R.id.txt_icon, obj.getiName()); } }; grid_photo.setAdapter(mAdapter); grid_photo.setOnItemClickListener(new AdapterView.OnItemClickListener() { @Override public void onItemClick(AdapterView<?> parent, View view, int position, long id) { Toast.makeText(mContext, "你点击了~" + position + "~项", Toast.LENGTH_SHORT).show(); } }); } }
嗯,代码非常简单~
3.示例代码下载:
本节小结:
本节给大家介绍了第二个需要使用Adapter的UI控件——网格视图GridView,用法很简单~ 大家可以根据自己的需求进行扩展,比如用GridView显示手机相册~嗯,就说这么多, 谢谢~