分类目录归档:Android

Android程序启动画面

public class SplashScreenTest extends Activity {
  /** Called when the activity is first created. */
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.splash);
    /** set time to splash out */
    final int welcomeScreenDisplay = 3000;
    new Handler().postDelayed(new Runnable(){
       @Override
       public void run() {
           Intent mainIntent = new Intent(SplashScreenTest.this,MainActivity.class);
           startActivity(mainIntent);
           finish();
       }
      }, welcomeScreenDisplay);
    }
}
public class MainActivity extends Activity {
  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    TextView textView = new TextView(this);
    textView.setText(“Main Activity”);
    setContentView(textView);
  }
}

svn checkout https://myandroidcode.googlecode.com/svn/trunk/SplashScreenTest

源代码
http://code.google.com/p/myandroidcode/source/browse/trunk/SplashScreenTest
 
 

Android创建sdcard详细图解

Android应用广泛,应用方式灵活,可以在模拟器中进行相应修改实现许多特定的功能需求。我们在这里就先来了解一下Android创建sdcard的具体方法,从中感受一下这一操作系统的相关特性。

Android创建sdcard步骤一、cmd进入tools目录输入mksdcard -l mycard 100M F:mysdcard.img

1. mycard命令可以使用三种尺寸:字节、K和M。如果只使用数字,表示字节。后面还可以跟K,如262144K,也表示256M。

2. mycard建立的虚拟文件最小为8M,也就是说,模拟器只支持大于8M的虚拟文件。

3. -l命令行参数表示虚拟磁盘的卷标,可以没有该参数。

4. 虚拟文件的扩展名可以是任意的,如mycard.abc。

5. mksdcard命令不会自动建立不存在的目录,因此,在执行上面命令之前,要先在当前目录中建立一个card目录。

6. mksdcard命令是按实际大小生成的sdcard虚拟文件。也就是说,生成256M的虚拟文件的尺寸就是256M,如果生成较大的虚拟文件,要看看自己的硬盘空间够不够哦!

Android创建sdcard步骤二、激活sdcard

1.命令行输入:emulator -avd my_android1.5 -sdcard F:mysdcard.img

我在命令行输入激活不了,不知为什么!待解决!

emulator: ERROR: the user data image is used by another emulator. aborting

2.如果在开发环境(Eclipse)中,可以在Run Configuration对话框中设置启动参数

或者在Preferences–>Android–>Launch加入

Android创建sdcard步骤三、sdcard中加入内容

F:android-sdk-windows-1.5_r3tools>adb push E:Xunleigive.mp3 /sdcard/give.mp3

android写Xml文件

废话少说,直接看代码

package cn.qing.xmltest;
import java.io.*;
import org.xmlpull.v1.XmlSerializer;
import android.app.Activity;
import android.os.*;
import android.util.*;
import android.widget.TextView;
public class wrXml extends Activity {
/** Called when the activity is first created. */
private String appDir;
private String xmlFileName;
StringBuilder sb;
TextView tv;
public wrXml(){
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
appDir = this.getApplicationContext().getFilesDir().getAbsolutePath();
xmlFileName = appDir + "/test.xml";
tv = new TextView(this);
sb = new StringBuilder();
writeXml();
tv.setText(sb.toString());
setContentView(tv);
}
private void writeXml() {
File xmlFile = new File(xmlFileName);
try {
xmlFile.createNewFile();
} catch (IOException e) {
Log.e("IOException", "exception in createNewFile() method");
}
FileOutputStream fileos = null;
try {
fileos = new FileOutputStream(xmlFile);
} catch (FileNotFoundException e) {
Log.e("FileNotFoundException", "can't create FileOutputStream");
}
XmlSerializer serializer = Xml.newSerializer();
try {
serializer.setOutput(fileos, "UTF-8");
serializer.startDocument(null, Boolean.valueOf(true));
serializer.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output",true);
serializer.startTag(null, "root");
serializer.startTag(null, "child1");
serializer.endTag(null, "child1");
serializer.startTag(null, "child2");
serializer.attribute(null, "attribute", "value");
serializer.endTag(null, "child2");
serializer.startTag(null, "child3");
serializer.text("some text inside child3");
serializer.endTag(null, "child3");
serializer.endTag(null, "root");
serializer.endDocument();
serializer.flush();
fileos.close();
sb.append("file has been created");
} catch (Exception e) {
Log.e("Exception", "error occurred while creating xml file");
sb.append("Create file error");
}
}
}