用GridLayout实现计算器的布局

package com.kale.gridlayout;

import android.app.Activity;
import android.os.Bundle;
import android.support.v7.widget.GridLayout;
import android.view.Gravity;
import android.widget.Button;

public class MainActivity extends Activity {
String [] chars = new String[]{
"7","8","9","÷",
"4","5","6","x",
"1","2","3","-",
".","0","=","+"
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);

GridLayout gLayout = (GridLayout)findViewById(R.id.root_gridLayout_id);
for (int i = 0; i < chars.length; i++) {
Button bt = new Button(this);
bt.setText(chars[i]);
bt.setTextSize(40);

//指定该组件所占的行
GridLayout.Spec rowSpec = GridLayout.spec(i/4 + 2);
//指定该组件所占的列
GridLayout.Spec columnSpec = GridLayout.spec(i % 4);
//按照设置好的行和列来建立对象
GridLayout.LayoutParams params = new GridLayout.LayoutParams(rowSpec,columnSpec);
//指定该组件占满父控件
params.setGravity(Gravity.FILL);
gLayout.addView(bt,params);
}

}
}

<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"
tools:context="${relativePackage}.${activityClass}"
xmlns:app="http://schemas.android.com/apk/res/com.kale.gridlayout">

<!-- 六行四列 -->
<android.support.v7.widget.GridLayout
android:id="@+id/root_gridLayout_id"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:rowCount="6"
app:columnCount="4">

<TextView
android:layout_width="match_parent"
android:layout_height="100dp"
app:layout_columnSpan="4"
android:text="Large Text"
android:textAppearance="?android:attr/textAppearanceLarge" />

<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:layout_gravity="center_horizontal|top"
app:layout_columnSpan="4"
android:text="Button" />
</android.support.v7.widget.GridLayout>

</RelativeLayout>