gridlaylout 简单布局

package com.example.gridlayout;


import android.app.Activity;
import android.os.Bundle;
import android.view.Gravity;
import android.widget.Button;
import android.widget.GridLayout;


public class MainGrid extends Activity {
    GridLayout grd;
    String[] chas=new String[]
            {
              "7","8","9","*"
              ,"4","5","6","/"
              ,"1","2","3","+"
              ,"0",".","=","-"
            
            };
    
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
       setContentView(R.layout.activity_main_grid);
        grd=(GridLayout)findViewById(R.id.root);
        for(int i=0;i<chas.length;i++)
        {
            Button bt=new Button(this);
             bt.setText(chas[i]);
             bt.setTextSize(40);
             bt.setHeight(200);
                GridLayout.Spec rowSpec = GridLayout.spec(i / 4 + 2);
                // 指定该组件所在列
                GridLayout.Spec columnSpec = GridLayout.spec(i % 4);
                GridLayout.LayoutParams params = new GridLayout.LayoutParams(
                        rowSpec , columnSpec);
                // 指定该组件占满父容器
                params.setGravity(Gravity.FILL);        
                grd.addView(bt , params);

        }
    }
}

<?xml version="1.0" encoding="utf-8" ?>
<GridLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" 
    android:rowCount="6"
    android:columnCount="4"
    android:id="@+id/root"
    >
<!-- 定义一个横跨4列的文本框，
并设置该文本框的前景色、背景色等属性  -->
<TextView 
    android:layout_width="match_parent"
    android:layout_height="wrap_content" 
    android:layout_columnSpan="4"
    android:textSize="50sp"
    android:layout_marginLeft="4px"
    android:layout_marginRight="4px"
    android:padding="5px"
    android:layout_gravity="right"
    android:background="#eee"
    android:textColor="#000"
    android:text="0"/>
<!-- 定义一个横跨4列的按钮 -->
<Button 
    android:layout_width="match_parent"
    android:layout_height="wrap_content" 
    android:layout_columnSpan="4"
    android:text="清除"/>
</GridLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.gridlayout"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk
        android:minSdkVersion="17"
        android:targetSdkVersion="21" />

    <application
        android:allowBackup="true"
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <activity
            android:name=".MainGrid"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>