The basic use of Android's GridView (grid view)

Introduction to this section:

This section introduces you to the second Adapter class control—GridView (grid view), as the name suggests, ListView is a list, and GridView is a display grid! He is a subclass of AbsListView like ListView! Many things are similar to ListView, in this section we will learn its basic usage~

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1. Related attributes:

Here are some properties in GridView:

• android:columnWidth : set the width of the column
• android:gravity : the way components align
• android:horizontalSpacing : the spacing of each cell in the horizontal direction
• android:verticalSpacing : the spacing of each cell in the vertical direction
• android:numColumns : set the number of columns
• android:stretchMode : Set the stretching mode, the optional values ​​are as follows:  none : No stretching; spacingWidth : Stretch the space between elements  columnWidth : Stretch only the table elements themselves  spacingWidthUniform : Stretch both the spacing between elements and the space between them Interval air strikes

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2. Example of use:

Let's use a simple example to familiarize yourself with the use of this control: (The Adapter we use here is the reusable BaseAdapter that we taught you to write in 2.5.0~)

Realized renderings :

Code implementation :

The first is the layout of the Item of the GridView: 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="hehe"
        android:textSize="18sp" />
        
</RelativeLayout>

Then we write an entity entity class: 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;
    }
}

Finally, the layout of MainActivity and Java code

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 sets how many to display per row -->
    <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, "Icon 1"));
        mData.add(new Icon(R.mipmap.iv_icon_2, "Icon 2"));
        mData.add(new Icon(R.mipmap.iv_icon_3, "Icon 3"));
        mData.add(new Icon(R.mipmap.iv_icon_4, "Icon 4"));
        mData.add(new Icon(R.mipmap.iv_icon_5, "Icon 5"));
        mData.add(new Icon(R.mipmap.iv_icon_6, "Icon 6"));
        mData.add(new Icon(R.mipmap.iv_icon_7, "Icon 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, "You clicked~" + position + "~item", Toast.LENGTH_SHORT).show();
            }
        });

    }

}