使用內容提供者讀取短信內容，寫入XML文件，進度條ProgressDialog更新備份進度。
新知識點：子線程如何在在不使用Handler的情況下更新UI
/** * 進行短信備份的工具類，支持進度條顯示 * @author lian * */ public class SmsBackupUtils { private static class Data{ int progress; } /** * * @param context * 調用此工具類的Activity * @param pd * 顯示備份進度的進度條 */ public static void smsBackup(Activity context,final ProgressDialog pd){ Uri uri = Uri.parse("content://sms/"); ContentResolver cr = context.getContentResolver(); //取出短信 final Cursor cursor = cr.query(uri, new String[]{"address","date","body","type"}, null, null, null); final int count = cursor.getCount(); final Data data = new Data(); data.progress = 0; //存儲路徑 File file = new File(Environment.getExternalStorageDirectory(), "sms.xml"); try { FileOutputStream fos = new FileOutputStream(file); PrintWriter pw = new PrintWriter(fos); //按照XML格式進行寫入 pw.println("<smses count='" + cursor.getCount() +"'>"); //在主線程中更新UI context.runOnUiThread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub pd.setMax(count); pd.show(); } }); //寫入XML文件 while(cursor.moveToNext()){ data.progress ++; String address = cursor.getString(0); String date = cursor.getString(1); String body = cursor.getString(2); String type = cursor.getString(3); //SystemClock.sleep(150); pw.println("<sms>"); pw.println("<address>"+ address +"</address>"); pw.println("<date>"+ date +"</date>"); pw.println("<body>"+ body +"</body>"); pw.println("<type>"+ type +"</type>"); pw.println("</sms>"); context.runOnUiThread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub pd.setProgress(data.progress); } }); } pw.println("</smses>"); pw.flush(); pw.close(); cursor.close(); //備份完成，關閉進度條 context.runOnUiThread(new Runnable() { @Override public void run() { // TODO Auto-generated method stub pd.dismiss(); } }); } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } } } 調用
pd = new ProgressDialog(this); pd.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); SmsBackupUtils.smsBackup(SuperToolActivity.this, pd);
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