搭建Android工程的步骤及其第一个安卓程序

JAVA_HOME=D:\Java\jdk1.8.0_91

CLASSPATH=.;%JAVA_HOME%\lib\dt.jar;%JAVA_HOME%\lib\tools.jar;%JAVA_HOME%\jre\lib\rt.jar

PATH=D:\Java\jdk1.8.0_91\bin;

校验

随便目录运行  java -version

1.配置一个环境变量ANDROID_HOME=D:\Java\adt-bundle-windows-x86_64-20140702\sdk

2.直接运行eclipse.exe

总结: eclipse不需要安装,我们使用安卓自带的eclipse即可

package com.example.androidhelloword;

import android.app.Activity;

import android.os.Bundle;

import android.view.Menu;

import android.view.MenuItem;

import android.widget.TextView;

public class MainActivity extends Activity {//继承了安卓API中的Activity类

@Override

protected void onCreate(Bundle savedInstanceState) {

super.onCreate(savedInstanceState);

setContentView(R.layout.activity_main); //加载布局

/**

* 查找控件通过Id

* this.findViewById(activity_main.xml文件中的某一控件的id)

*/

  TextView v =  (TextView) this.findViewById(R.id.textView1);

//修改指定id的控件的内容

  v.setText(“呵呵”);

}

@Override

public boolean onCreateOptionsMenu(Menu menu) {

// Inflate the menu; this adds items to the action bar if it is present.

getMenuInflater().inflate(R.menu.main, menu);

return true;

}

@Override

public boolean onOptionsItemSelected(MenuItem item) {

// Handle action bar item clicks here. The action bar will

// automatically handle clicks on the Home/Up button, so long

// as you specify a parent activity in AndroidManifest.xml.

int id = item.getItemId();

if (id == R.id.action_settings) {

return true;

}

return super.onOptionsItemSelected(item);

}

}

<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:paddingBottom=“@dimen/activity_vertical_margin”

android:paddingLeft=“@dimen/activity_horizontal_margin”

android:paddingRight=“@dimen/activity_horizontal_margin”

android:paddingTop=“@dimen/activity_vertical_margin”

tools:context=“com.example.androidhelloword.MainActivity” >

<TextView

android:id=“@+id/textView1”

android:layout_width=“wrap_content”

android:layout_height=“wrap_content”

android:text=“@string/hello_world” />

<Button

android:id=“@+id/button1”

android:layout_width=“wrap_content”

android:layout_height=“wrap_content”

android:layout_alignLeft=“@+id/textView1”

android:layout_below=“@+id/textView1”

android:layout_marginLeft=“23dp”

android:layout_marginTop=“57dp”

android:text=“Button” />

<Button

android:id=“@+id/button2”

android:layout_width=“wrap_content”

android:layout_height=“wrap_content”

android:layout_alignBaseline=“@+id/button1”

android:layout_alignBottom=“@+id/button1”

android:layout_marginLeft=“37dp”

android:layout_toRightOf=“@+id/button1”

android:text=“Button” />

</RelativeLayout>

总结: 当每次对控件进行操作的时候,都会在这个文件中自动的生成控件的代码,而每一个控件的代码都有一个id,而这个id唯一的标识了每一个控件

package com.example.androidhelloword;

public final class R {

public static final class attr {

}

public static final class dimen {

/**  Default screen margins, per the Android Design guidelines.

Example customization of dimensions originally defined in res/values/dimens.xml

(such as screen margins) for screens with more than 820dp of available width. This

would include 7″ and 10″ devices in landscape (~960dp and ~1280dp respectively).

*/

public static final int activity_horizontal_margin=0x7f040000;

public static final int activity_vertical_margin=0x7f040001;

}

public static final class drawable {

public static final int ic_launcher=0x7f020000;

}

/**

*

* 当每添加一个控件的时候,都会在R.java文件的id内部类中添加一个控件的id

* 用于标识activity_main.xml文件中的控件

*/

 public static final class id {

        public static final int action_settings=0x7f080003;

        public static final int button1=0x7f080001;

        public static final int button2=0x7f080002;

        public static final int textView1=0x7f080000;

}

public static final class layout {

public static final int activity_main=0x7f030000;

}

public static final class menu {

public static final int main=0x7f070000;

}

public static final class string {

public static final int action_settings=0x7f050002;

public static final int app_name=0x7f050000;

public static final int hello_world=0x7f050001;

}

public static final class style {

/**

Base application theme, dependent on API level. This theme is replaced

by AppBaseTheme from res/values-vXX/styles.xml on newer devices.

Theme customizations available in newer API levels can go in

res/values-vXX/styles.xml, while customizations related to

backward-compatibility can go here.

Base application theme for API 11+. This theme completely replaces

AppBaseTheme from res/values/styles.xml on API 11+ devices.

API 11 theme customizations can go here.

Base application theme for API 14+. This theme completely replaces

AppBaseTheme from BOTH res/values/styles.xml and

res/values-v11/styles.xml on API 14+ devices.

API 14 theme customizations can go here.

*/

public static final int AppBaseTheme=0x7f060000;

/**  Application theme.

All customizations that are NOT specific to a particular API-level can go here.

*/

public static final int AppTheme=0x7f060001;

}

}