今天來總結下,掃碼槍遇到的一些問題。(ps:參考了http://blog.csdn.net/czhpxl007/article/details/50363766 博主的文章)
剛開始掃碼用的是EditText
EditText editText = (EditText) findViewById(R.id.edittext);
editText.addTextChangedListener(watcher);
private TextWatcher watcher = new TextWatcher() {
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
// TODO Auto-generated method stub
//在這個實現掃碼
//固定s的長度,侷限了掃碼,而且還有一個問題就是掃的太快,條形碼亂碼了~之後百度了很久,好不容易找到一篇參考的
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
// TODO Auto-generated method stub
}
@Override
public void afterTextChanged(Editable s) {
// TODO Auto-generated method stub
}
};
因爲我不需要用到藍牙 ,就參考博主的修改了~~
/*掃碼搶解析類/
public class ScanGunKeyEventHelper {
private final static long MESSAGE_DELAY = 50; // 延遲50ms,判斷掃碼是否完成。
private StringBuffer mStringBufferResult; // 掃碼內容
private boolean mCaps; // 大小寫區分
private final Handler mHandler;
private final Runnable mScanningFishedRunnable;
private OnScanSuccessListener mOnScanSuccessListener;
public ScanGunKeyEventHelper(OnScanSuccessListener onScanSuccessListener) {
mOnScanSuccessListener = onScanSuccessListener;
mStringBufferResult = new StringBuffer();
mHandler = new Handler();
mScanningFishedRunnable = new Runnable() {
@Override
public void run() {
performScanSuccess();
}
};
}
/**
* 返回掃碼成功後的結果
*/
private void performScanSuccess() {
String barcode = mStringBufferResult.toString();
if (mOnScanSuccessListener != null) {
mOnScanSuccessListener.onScanSuccess(barcode);
}
mStringBufferResult.setLength(0);
}
/**
* 掃碼槍事件解析
*
* @param event
*/
public void analysisKeyEvent(KeyEvent event) {
int keyCode = event.getKeyCode();
// 字母大小寫判斷
checkLetterStatus(event);
if (event.getAction() == KeyEvent.ACTION_DOWN) {
char aChar = getInputCode(event);
if (aChar != 0) {
mStringBufferResult.append(aChar);
}
if (keyCode == KeyEvent.KEYCODE_ENTER) {
// 若爲回車鍵,直接返回
mHandler.removeCallbacks(mScanningFishedRunnable);
mHandler.post(mScanningFishedRunnable);
} else {
// 延遲post,若50ms內,有其他事件
mHandler.removeCallbacks(mScanningFishedRunnable);
mHandler.postDelayed(mScanningFishedRunnable, MESSAGE_DELAY);
}
}
}
// 檢查shift鍵
private void checkLetterStatus(KeyEvent event) {
int keyCode = event.getKeyCode();
if (keyCode == KeyEvent.KEYCODE_SHIFT_RIGHT || keyCode == KeyEvent.KEYCODE_SHIFT_LEFT) {
// 按着shift鍵,表示大寫
// 鬆開shift鍵,表示小寫
mCaps = (event.getAction() == KeyEvent.ACTION_DOWN);
}
}
// 獲取掃描內容
private char getInputCode(KeyEvent event) {
int keyCode = event.getKeyCode();
char aChar;
if (keyCode >= KeyEvent.KEYCODE_A && keyCode <= KeyEvent.KEYCODE_Z) {
// 字母
aChar = (char) ((mCaps ? 'A' : 'a') + keyCode - KeyEvent.KEYCODE_A);
} else if (keyCode >= KeyEvent.KEYCODE_0 && keyCode <= KeyEvent.KEYCODE_9) {
// 數字
aChar = (char) ('0' + keyCode - KeyEvent.KEYCODE_0);
} else {
// 其他符號
switch (keyCode) {
case KeyEvent.KEYCODE_PERIOD:
aChar = '.';
break;
case KeyEvent.KEYCODE_MINUS:
aChar = mCaps ? '_' : '-';
break;
case KeyEvent.KEYCODE_SLASH:
aChar = '/';
break;
case KeyEvent.KEYCODE_BACKSLASH:
aChar = mCaps ? '|' : '\\';
break;
default:
aChar = 0;
break;
}
}
return aChar;
}
public interface OnScanSuccessListener {
void onScanSuccess(String barcode);
}
public void onDestroy() {
mHandler.removeCallbacks(mScanningFishedRunnable);
mOnScanSuccessListener = null;
}
}
在activity
public class MainActivity extends Activity implements ScanGunKeyEventHelper.OnScanSuccessListener {
private ScanGunKeyEventHelper scanGunKeyEventHelper = null;//掃碼
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main_layout);
scanGunKeyEventHelper = new ScanGunKeyEventHelper(this);
}
@Override
public boolean dispatchKeyEvent(KeyEvent event) {
scanGunKeyEventHelper.analysisKeyEvent(event);
return super.dispatchKeyEvent(event);
}
@Override
protected void onDestroy() {
super.onDestroy();
scanGunKeyEventHelper.onDestroy();
}
@Override
public void onScanSuccess(String barcode) {
//barcode 條形碼
//在這裏實現相關操作
}
}