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我目前正在創建一個程序，遞歸搜索android手機上的視頻的SD卡，然後生成每個視頻的散列。Android UI不更新
一切工作正常，但是當我試圖創建一個progress bar，在progress bar不更新，直到結束。
所以基本上進度條的進度似乎從0轉到最大，但我可以從日誌輸出告訴值被髮送到進度條進行更新，進度條只是不upating。
我的代碼如下：
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
progress = (ProgressBar) findViewById(R.id.progressBar1);
text = (TextView) findViewById(R.id.tv1);
Button btnStart = (Button) findViewById(R.id.btnStart);
btnStart.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
recursiveVideoFinder(new File("/sdcard"));
String strDB3File = getFilesDir().getPath()
+ "/VideoHashes.db3";
sql3 = SQLiteDatabase.openDatabase(strDB3File, null,
SQLiteDatabase.CREATE_IF_NECESSARY);
try {
String mysql = "CREATE TABLE videohashes (id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT, path TEXT NOT NULL, hash TEXT NOT NULL, date TEXT NOT NULL, size INTEGER)";
sql3.execSQL(mysql);
} catch (SQLiteException e) {
// TODO: handle exception
}
progress.setProgress(0);
progress.setMax(myFiles.size());
for (String path : myFiles) {
try {
String hash = getMD5Checksum(path);
ContentValues myInsertData = new ContentValues();
myInsertData.put("path", path);
myInsertData.put("hash", hash);
Date date = new Date();
myInsertData.put("date", dateFormat.format(date));
myInsertData.put("size", getFileSize(path));
sql3.insert("videohashes", null, myInsertData);
currVid++;
updateProgress();
Log.i("Progress", "CurrVid:" + currVid + " Max:"
+ progress.getMax());
text.append(currVid + " ");
} catch (Exception e) {
Log.i("File", "File not Found");
}
}
Cursor cur = sql3.query("videohashes", null, null, null, null,
null, null);
cur.moveToFirst();
while (!cur.isAfterLast()) {
/*
* ((TextView) findViewById(R.id.tv1)).append("\n" +
* cur.getString(1) + "\n" + cur.getString(2) + "\n" +
* cur.getString(3) + "\n" + cur.getString(4) + "\n");
*/
cur.moveToNext();
}
cur.close();
}
});
}
public long getFileSize(String path) {
File file = new File(path);
return file.length();
}
private void recursiveVideoFinder(File _dir) {
File[] files = _dir.listFiles();
if (files == null) {
return;
}
for (File currentFile : files) {
if (currentFile.isDirectory()) {
recursiveVideoFinder(currentFile);
continue;
} else {
for (String aEnd : getResources().getStringArray(
R.array.VideoExtensions)) {
if (currentFile.getName().endsWith(aEnd)) {
Log.d("PS:", currentFile.getPath().toString());
String videoFileName = currentFile.getPath().toString();
myFiles.add(videoFileName);
}
}
}
}
}
// Code based off this example:
// http://stackoverflow.com/questions/304268/getting-a-files-md5-checksum-in-java
public static byte[] createCheckSum(String filename) throws Exception {
InputStream fis = new FileInputStream(filename);
byte[] buffer = new byte[1024];
MessageDigest complete = MessageDigest.getInstance("MD5");
int numRead;
do {
numRead = fis.read(buffer);
if (numRead > 0) {
complete.update(buffer, 0, numRead);
}
} while (numRead != -1);
fis.close();
// Return MD5 Hash
return complete.digest();
}
public String getMD5Checksum(String filename) throws Exception {
byte[] b = createCheckSum(filename);
String result = "";
for (int i = 0; i < b.length; i++) {
result += Integer.toString((b[i] & 0xff) + 0x100, 16).substring(1);
}
return result;
}
public void updateProgress() {
progress.setProgress(currVid);
progress.invalidate();
Log.i("Updating", "Updating Progress Bar");
}
}
此問題不僅限於進度條。我無法更新textview的。它們在這裏包含的代碼上方聲明，但我沒有包含該部分。我確信他們宣佈正確。 – johns4ta 2012-04-13 02:35:45
'for循環'在ui線程中運行，它可能會阻塞ui，所以不能更新ui，你可以在後臺線程中做'for循環'嗎？ – idiottiger 2012-04-13 02:46:02
在我的原始代碼中，我將它放在單獨的線程中，但不是後臺線程，它仍然存在相同的問題。我會嘗試後臺線程，並讓你知道它是怎麼回事。謝謝。 – johns4ta 2012-04-13 12:01:09