UI和View 三种控制方式

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.hanqi.test6">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".Activity1">

        </activity>

        <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>

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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="com.hanqi.test6.MainActivity"

    android:orientation="vertical"><!--orientation改方向   vertical垂直-->

    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="按钮一"
        />
    <Button
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="按钮二"
        android:id="@+id/button2"
        />

</LinearLayout>

MainActivity

package com.hanqi.test6;

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        //获取文件findViewById
        Button button2 = (Button)findViewById(R.id.button2);
        //设置setText
        button2.setText("新按钮名");
    }
}

Activity1

package com.hanqi.test6;

import android.os.Bundle;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.AppCompatActivity;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.LinearLayout;

/**
 * Created by Administrator on 2016/3/22.
 */
public class Activity1 extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        //创建布局管理器  LinearLayout线性布局
        LinearLayout linearLayout = new LinearLayout(this);
        //setOrientation 布局方向   VERTICAL垂直
        linearLayout.setOrientation(LinearLayout.VERTICAL);
        //setLayoutParams属性   创建属性集合
        linearLayout.setLayoutParams(
                new DrawerLayout.LayoutParams(
                        ViewGroup.LayoutParams.MATCH_PARENT,
                        ViewGroup.LayoutParams.MATCH_PARENT));

        Button button = new Button(this);
        //设置显示的内容
        button.setText("按钮二");
        //setLayoutParams属性   创建属性集合
        button.setLayoutParams(
                new DrawerLayout.LayoutParams(
                    ViewGroup.LayoutParams.WRAP_CONTENT,
                    ViewGroup.LayoutParams.WRAP_CONTENT));

        //把View放到布局里去   addView添加布局
        linearLayout.addView(button);
        button.setText("按钮三");
        //setLayoutParams属性   创建属性集合
        button.setLayoutParams(
                new DrawerLayout.LayoutParams(
                        ViewGroup.LayoutParams.WRAP_CONTENT,
                        ViewGroup.LayoutParams.WRAP_CONTENT));

        //把View放到布局里去   addView添加布局
        linearLayout.addView(button);
        //关联布局管理器  setContentView关联
        setContentView(linearLayout);
    }
}