This article describes the Android method to get the SD card path and SDCard memory. Share to everybody for everybody reference. The specific analysis is as follows:
Yesterday, after studying the problem of the storage path broken through after taking photos, the storage path began to be written dead as: private String folder = “/sdcard/DCIM/Camera/” (the image storage path of SD card camera program); It turns out that although 1 doesn’t make any mistakes, it’s not very good, because different cameras may cause problems with the path. A better way is to get the path through Environment. Finally, give me an example of how to get the memory of SDCard. The content is as follows:
0. Get the path of sd card. 1. Describe the Environment class. 2. Describe the StatFs class. 3. Complete example to read SDCard memory
0. Get the path of sd card
Method 1:
private String folder = "/sdcard/DCIM/Camera/" ( SD Image storage path of the camera program on the card) ; // Write dead absolute path, do not approve of useMethod 2:
public String getSDPath(){
File sdDir = null;
boolean sdCardExist = Environment.getExternalStorageState()
.equals(android.os.Environment.MEDIA_MOUNTED);// judge sd Whether the card exists
if(sdCardExist)
{
sdDir = Environment.getExternalStorageDirectory();// Get trace directory
}
return sdDir.toString();
}Then: Follow by a slash, followed by a file name
String fileName = getSDPath() +"/" + name;// In order to name Stored in the directory1. Describe the Environment class
Environment is a class that provides access to environment variables. Environment contains constants:
MEDIA_BAD_REMOVAL Explanation: Returns getExternalStorageState() to indicate that SDCard was removed before it was uninstalled MEDIA_CHECKING Explanation: Returns getExternalStorageState(), indicating that the object is being checked on disk. MEDIA_MOUNTED Explanation: Returns getExternalStorageState(), indicating whether the object exists and has read/write permissions MEDIA_MOUNTED_READ_ONLY Explanation: Returns getExternalStorageState(), indicating that object permissions are read-only MEDIA_NOFS Explanation: Returns getExternalStorageState(), indicating that the object is blank or using an unsupported file system. MEDIA_REMOVED Explanation: returns getExternalStorageState(), if no SDCard exists MEDIA_SHARED Explanation: returns getExternalStorageState() if SDCard is not installed and via USB mass storage share MEDIA_UNMOUNTABLE Explanation: Return getExternalStorageState(), return SDCard cannot be installed if SDCard exists but cannot be installed MEDIA_UNMOUNTED Explanation: Return getExternalStorageState(), return SDCard uninstalled if SDCard is present but not installed
Common methods of Environment:
Methods: getDataDirectory () Explanation: Return File for the Android data directory. Methods: getDownloadCacheDirectory () Explanation: Return File for the Android download/cache content directory. Methods: getExternalStorageDirectory () Explanation: Return File to get the external storage directory, SDCard Methods: getExternalStoragePublicDirectory(String type) Explanation: Back to File, take a high level common external storage directory to put some types of files in Methods: getExternalStorageState () Explanation: Returns File for the current state of the external storage device Methods: getRootDirectory () Explanation: Return File for the root directory of Android 2. Describe the StatFs class StatFs 1 class emulates linux’s df command to get SD card and phone memory usage StatFs Common methods:
getAvailableBlocks() Explanation: Returns Int for the currently available storage space getBlockCount() Explanation: Returns Int for the number of file systems available in this area getBlockSize() Explanation: Returns Int, size in bytes, 1 file system getFreeBlocks() Explanation: Returns Int, the remaining space in the block restat(String path) Explanation: Executes a file system referenced by the object 3. Complete example to read SDCard memory The memory card can be plugged and unplugged at any time on the Android mobile phone. Each action will cause ACTION_BROADCAST to the operating system. This example will use the method learned above to calculate the remaining capacity and total capacity of SDCard. The code is as follows:
package com.terry;
import java.io.File;
import java.text.DecimalFormat;
import android.R.integer;
import android.app.Activity;
import android.os.Bundle;
import android.os.Environment;
import android.os.StatFs;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ProgressBar;
import android.widget.TextView;
import android.widget.Toast;
public class getStorageActivity extends Activity {
private Button myButton;
/** Called when the activity is first created. */
@Override
public
void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
findView();
viewHolder.myButton.setOnClickListener(new OnClickListener() {
@Override
public
void onClick(View arg0) {
// TODO Auto-generated method stub
getSize();
}
});
}
void findView(){
viewHolder.myButton=(Button)findViewById(R.id.Button01);
viewHolder.myBar=(ProgressBar)findViewById(R.id.myProgressBar);
viewHolder.myTextView=(TextView)findViewById(R.id.myTextView);
}
void getSize(){
viewHolder.myTextView.setText("");
viewHolder.myBar.setProgress(0);
// Determine if there is an insert memory card
if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
File path =Environment.getExternalStorageDirectory();
// achieve sdcard The file path
StatFs statfs=new StatFs(path.getPath());
// To obtain block the SIZE
long blocSize=statfs.getBlockSize();
// To obtain BLOCK The number of
long totalBlocks=statfs.getBlockCount();
// F the use of Block The number of
long availaBlock=statfs.getAvailableBlocks();
String[] total=filesize(totalBlocks*blocSize);
String[] availale=filesize(availaBlock*blocSize);
// Sets the maximum value of the progress bar
int maxValue=Integer.parseInt(availale[0])
*viewHolder.myBar.getMax()/Integer.parseInt(total[0]);
viewHolder.myBar.setProgress(maxValue);
String Text=" A total of: "+total[0]+total[1]+"/n"
+" available :"+availale[0]+availale[1];
viewHolder.myTextView.setText(Text);
}else
if(Environment.getExternalStorageState().equals(Environment.MEDIA_REMOVED)){
Toast.makeText(getStorageActivity.this, " There is no sdCard",1000).show();
}
}
// Returns an array, subscript 1 It's the magnitude, the subscript 2 On behalf of the unit KB/MB
String[] filesize(long size){
String str="";
if(size>=1024){
str="KB";
size/=1024;
if(size>=1024){
str="MB";
size/=1024;
}
}
DecimalFormat formatter=new DecimalFormat();
formatter.setGroupingSize(3);
String result[] =new String[2];
result[0]=formatter.format(size);
result[1]=str;
return result;
}
}I hope this article has been helpful for your Android programming.