Android 检测SD卡是否可用

做软件的时候 也许要存数据要用到SD卡 所以在用之前 最好检测下 SD卡是否可用
下面是java代码

import java.io.File;
import java.util.Date;
import android.content.BroadcastReceiver;
import android.content.Context;
import android.content.Intent;

public class SDCardListener extends BroadcastReceiver {

	private static boolean sdcardAvailable;
	private static boolean sdcardAvailabilityDetected;

	
	/**
	 * 
	 * @return SD is available ?
	 */
	public static synchronized boolean detectSDCardAvailability() {
		boolean result = false;
		try {
			Date now = new Date();
			long times = now.getTime();
			String fileName = "/sdcard/" + times + ".test";
			File file = new File(fileName);
			result = file.createNewFile();
			file.delete();
		} catch (Exception e) {
			// Can't create file, SD Card is not available
			e.printStackTrace();
		} finally {
			sdcardAvailabilityDetected = true;
			sdcardAvailable = result;
		}
		return result;
	}
	
	/**
	 * 
	 * @return SD is available ?
	 */
	public static boolean isSDCardAvailable() {
		if(!sdcardAvailabilityDetected) {
			sdcardAvailable = detectSDCardAvailability();
			sdcardAvailabilityDetected = true;
		}
		return  sdcardAvailable;
	}
	
	/* (non-Javadoc)
	 * @see android.content.BroadcastReceiver#onReceive(android.content.Context, android.content.Intent)
	 */	
	public void onReceive(Context context, Intent intent) {
		sdcardAvailabilityDetected = false;
		sdcardAvailable = detectSDCardAvailability();
		sdcardAvailabilityDetected = true;
	}

}

然后在 AndroidManifest.xml中写下以下的话

<receiver android:name=".SDCardListener">
			<intent-filter>
				<action android:name="android.intent.action.MEDIA_EJECT" />
				<action android:name="android.intent.action.MEDIA_MOUNTED" />
				<action android:name="android.intent.action.MEDIA_REMOVED" />
				<action android:name="android.intent.action.MEDIA_UNMOUNTED" />
				<data android:scheme="file" />
			</intent-filter>
		</receiver>

搞定

如果觉得上面那种方法太麻烦了 我给出一个超简单的判断方法
代码如下

if (Environment.getExternalStorageState().equals(
					Environment.MEDIA_MOUNTED)) {
				// sd card 可用
					
				}else {
// 当前不可用
}