Android 动态创建控件

 1 package com.metrox.absolutelayoutdemo;
 2 
 3 import android.support.v7.app.AppCompatActivity;
 4 import android.os.Bundle;
 5 import android.view.Gravity;
 6 import android.widget.Button;
 7 import android.widget.GridLayout;
 8 
 9 public class MainActivity extends AppCompatActivity {
10 
11     String[] chars = new String[]{
12             "7","8","9","÷",
13             "4","5","6","×",
14             "1","2","3","-",
15             ".","0","=","+"
16     };
17     @Override
18     protected void onCreate(Bundle savedInstanceState) {
19         super.onCreate(savedInstanceState);
20         setContentView(R.layout.activity_main);
21         GridLayout demogrid = (GridLayout)findViewById(R.id.root);
22         for (int i = 0;i<chars.length;i++){
23             Button bn = new Button(this);
24             bn.setText(chars[i]);
25             bn.setTextSize(40);
26             bn.setPadding(5, 30, 5, 30);
27             GridLayout.Spec rowSpec = GridLayout.spec(i / 4 + 2);
28             GridLayout.Spec columnSpec = GridLayout.spec(i % 4);
29             GridLayout.LayoutParams params = new GridLayout.LayoutParams(rowSpec,columnSpec);
30             params.setGravity(Gravity.FILL);
31             demogrid.addView(bn,params);
32         }
33     }
34 }

 1 <?xml version="1.0" encoding="utf-8"?>
 2 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
 3     xmlns:tools="http://schemas.android.com/tools"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:paddingBottom="@dimen/activity_vertical_margin"
 7     android:paddingLeft="@dimen/activity_horizontal_margin"
 8     android:paddingRight="@dimen/activity_horizontal_margin"
 9     android:paddingTop="@dimen/activity_vertical_margin"
10     tools:context="com.metrox.absolutelayoutdemo.MainActivity">
11 
12     <GridLayout
13         android:layout_width="match_parent"
14         android:layout_height="match_parent"
15         android:columnCount="4"
16         android:rowCount="6"
17         android:id="@+id/root">
18 
19         <TextView
20             android:layout_width="match_parent"
21             android:layout_height="wrap_content"
22             android:text="0"
23             android:id="@+id/textView"
24             android:layout_columnSpan="4"
25             android:layout_marginLeft="2pt"
26             android:layout_marginRight="2pt"
27             android:padding="3pt"
28             android:gravity="right"
29             android:textSize="35sp"
30             android:background="#eee"
31             android:textColor="#000" />
32 
33         <Button
34             android:layout_width="match_parent"
35             android:layout_height="wrap_content"
36             android:text="清除"
37             android:layout_columnSpan="4"
38             android:id="@+id/button" />
39     </GridLayout>
40 </RelativeLayout>

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.metrox.absolutelayoutdemo">

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

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

</manifest>