Camera.java??????????????????????????????????????????????????????????????????????????

• autoFocus()聚焦回調函數

@Overridepublic void autoFocus() {//記錄當前聚焦開始時間mFocusStartTime = System.currentTimeMillis();//設置Camera的回調聚焦 mCameraDevice.autoFocus(mAutoFocusCallback);//設置Camera的狀態為Focusing setCameraState(FOCUSING);}

• 設置相機狀態

private void setCameraState(int state) {mCameraState = state;switch (state) {case SNAPSHOT_IN_PROGRESS:case FOCUSING:enableCameraControls(false);break;case IDLE:case PREVIEW_STOPPED:enableCameraControls(true);break;}}

• enableCameraControls，設置enable，是否可以點擊

/*** 設置幾個button或者view不可點擊* @param enable*/private void enableCameraControls(boolean enable) {if (mIndicatorControlContainer != null) {mIndicatorControlContainer.setEnabled(enable);}if (mModePicker != null) mModePicker.setEnabled(enable);if (mZoomControl != null) mZoomControl.setEnabled(enable);if (mThumbnailView != null) mThumbnailView.setEnabled(enable);}

• mIndicatorControlContainer的enable的設置

Overridepublic void setEnabled(boolean enabled) {super.setEnabled(enabled);final int count = getChildCount();for (int i = 0; i < count; i++) {View v = getChildAt(i);// Zoom buttons and shutter button are controlled by the activity.if (v instanceof AbstractIndicatorButton) {v.setEnabled(enabled);// Show or hide the indicator buttons during recording.if (mCurrentMode == MODE_VIDEO) {v.setVisibility(enabled ? View.VISIBLE : View.INVISIBLE);}}}if (mCameraPicker != null) {mCameraPicker.setEnabled(enabled);if (mCurrentMode == MODE_VIDEO) {mCameraPicker.setVisibility(enabled ? View.VISIBLE : View.INVISIBLE);}}}

• mAutoFocusCallback中的處理

private final class AutoFocusCallbackimplements android.hardware.Camera.AutoFocusCallback {public void onAutoFocus(boolean focused, android.hardware.Camera camera) {//如果是暫停狀態，不聚焦if (mPausing) return;//算出當前到聚焦開始的時間差mAutoFocusTime = System.currentTimeMillis() - mFocusStartTime;Log.v(TAG, "mAutoFocusTime = " + mAutoFocusTime + "ms");//設置Camera狀態為 setCameraState(IDLE);//調用FocusManager中的AutoFocus mFocusManager.onAutoFocus(focused);}}

FocusManager.java??????????????????????????????????????????????????????????????????

/*** 聚焦* @param focused*/public void onAutoFocus(boolean focused) {Log.i(TAG, "focus used : " + (System.currentTimeMillis() - focusStart));//正在進行聚焦，拍照動作必須再聚焦完之后if (mState == STATE_FOCUSING_SNAP_ON_FINISH) {// 無論聚焦成功還是失敗，都會拍照。如果要進行拍照發聲，就無需AF發聲了if (focused) {//聚焦成功mState = STATE_SUCCESS;} else {//聚焦失敗mState = STATE_FAIL;}//更新聚焦框UI&&設置人臉識別UI已經各種狀態的設置 updateFocusUI();//拍照，mState的狀態變為STATE_IDLE capture();} else if (mState == STATE_FOCUSING) {//如果是聚焦中的狀態//此狀態的發生分為兩種，half-pressing按壓聚焦或者觸摸聚焦被觸發，這個時候不要發生拍照動作if (focused) {//聚焦成功mState = STATE_SUCCESS;//在連續聚焦狀態不要發聲，聚焦回調會在拍照前完成，所有狀態一直為STATE_FOCUSINGif (!Parameters.FOCUS_MODE_CONTINUOUS_PICTURE.equals(mFocusMode)) {mListener.playSound(CameraSound.FOCUS_COMPLETE);}} else {//聚焦失敗mState = STATE_FAIL;}//更新聚焦&&人臉UI updateFocusUI();// If this is triggered by touch focus, cancel focus after a// while.//如果是觸摸聚焦，需要延遲一下取消掉聚焦if (mFocusArea != null) {mHandler.sendEmptyMessageDelayed(RESET_TOUCH_FOCUS, RESET_TOUCH_FOCUS_DELAY);}} else if (mState == STATE_IDLE) {//空閑// User has released the focus key before focus completes.// Do nothing. }}

• 處理消息

private class MainHandler extends Handler {@Overridepublic void handleMessage(Message msg) {switch (msg.what) {case RESET_TOUCH_FOCUS: {//取消掉聚焦 cancelAutoFocus();//開始人臉識別 mListener.startFaceDetection();break;}}}} /*** 再重置tap area之前調用mListener.cancelAutofocus，否則，聚焦模式將一直是自動&tap聚焦，并且驅動也不會重置*/private void cancelAutoFocus() {//放置聚焦框到屏幕中間 resetTouchFocus();mListener.cancelAutoFocus();if (mFaceView != null) mFaceView.resume();mState = STATE_IDLE;updateFocusUI();mHandler.removeMessages(RESET_TOUCH_FOCUS);}

• 觸摸聚焦

/*** 觸摸，，這里會發生觸摸聚焦* @param e* @return*/public boolean onTouch(MotionEvent e) {//沒有初始化或者拍照前的聚焦的狀態，直接返回if (!mInitialized || mState == STATE_FOCUSING_SNAP_ON_FINISH) return false;//讓用戶可以取消掉之前未消失的觸摸聚焦if ((mFocusArea != null) && (mState == STATE_FOCUSING ||mState == STATE_SUCCESS || mState == STATE_FAIL)) {cancelAutoFocus();}// Initialize variables.int x = Math.round(e.getX());int y = Math.round(e.getY());int focusWidth = mFocusIndicatorRotateLayout.getWidth();int focusHeight = mFocusIndicatorRotateLayout.getHeight();int previewWidth = mPreviewFrame.getWidth();int previewHeight = mPreviewFrame.getHeight();if (mFocusArea == null) {mFocusArea = new ArrayList<Area>();mFocusArea.add(new Area(new Rect(), 1));mMeteringArea = new ArrayList<Area>();mMeteringArea.add(new Area(new Rect(), 1));}//將坐標轉換為驅動的格式。AE面積更大,因為曝光會敏感和容易，或者說曝光不足,如果面積太小了。 calculateTapArea(focusWidth, focusHeight, 1f, x, y, previewWidth, previewHeight,mFocusArea.get(0).rect);calculateTapArea(focusWidth, focusHeight, 1.5f, x, y, previewWidth, previewHeight,mMeteringArea.get(0).rect);// Use margin to set the focus indicator to the touched area.RelativeLayout.LayoutParams p =(RelativeLayout.LayoutParams) mFocusIndicatorRotateLayout.getLayoutParams();int left = Util.clamp(x - focusWidth / 2, 0, previewWidth - focusWidth);int top = Util.clamp(y - focusHeight / 2, 0, previewHeight - focusHeight);p.setMargins(left, top, 0, 0);// Disable "center" rule because we no longer want to put it in the center.int[] rules = p.getRules();rules[RelativeLayout.CENTER_IN_PARENT] = 0;mFocusIndicatorRotateLayout.requestLayout();//停止人臉識別，因為要進行識別聚焦和測量area mListener.stopFaceDetection();//設置聚焦區域&測量區域 mListener.setFocusParameters();//如果支持觸摸聚焦&&手指抬起if (mFocusAreaSupported && (e.getAction() == MotionEvent.ACTION_UP)) {autoFocus();} else { // Just show the indicator in all other cases. updateFocusUI();// Reset the metering area in 3 seconds. mHandler.removeMessages(RESET_TOUCH_FOCUS);mHandler.sendEmptyMessageDelayed(RESET_TOUCH_FOCUS, RESET_TOUCH_FOCUS_DELAY);}return true;}

聚焦各個狀態能做什么事不能做什么事&切換???????????????????????????????????????

• STATE_IDLE

doSnap()：空閑狀態可以執行拍照 onAutoFocus(boolean focused)：用戶再聚焦完成前放掉了聚焦按鈕，所以不做任何事。 onPreviewStarted()，onPreviewStopped()：狀態都變為空閑 cancelAutoFocus()：取消聚焦，狀態變為空閑 updateFocusUI()：如果空閑&有聚焦區域，顯示聚焦框框

• STATE_FOCUSING

onShutterUp()：如果是focusmode為自動聚焦，狀態為正在聚焦，則取消掉聚焦 doSnap()：如果是正在聚焦狀態，將狀態改為聚焦完拍照狀態 onAutoFocus(boolean focused)：判斷focused，為true變為聚焦成功狀態，為false變為聚焦失敗狀態 onTouch(MotionEvent e)：如果正在聚焦&之前有手動聚焦了，則取消掉之前的聚焦 autoFocus()：狀態變為聚焦狀態 updateFocusUI()：顯示聚焦的框框

• STATE_FOCUSING_SNAP_ON_FINISH

onShutterUp()：狀態不是聚焦完拍照，可以設置FocusParameters onAutoFocus(boolean focused)：判斷focused，為true變為聚焦成功狀態，為false變為聚焦失敗狀態，更新聚焦框UI onTouch(MotionEvent e)：直接不繼續操作下去 updateFocusUI()：顯示聚焦的框框

• STATE_SUCCESS

onShutterDown()：如果是自動聚焦mode，并且不為聚焦成功狀態，執行聚焦 onShutterUp()： 如果是自動聚焦mode，并且為聚焦成功狀態，執行取消聚焦 doSnap()：拍照 onTouch(MotionEvent e)：讓用戶可以取消掉之前未消失的觸摸聚焦 updateFocusUI()：聚焦框框顯示成功

• STATE_FAIL

onShutterDown()：如果是自動聚焦mode，并且不為聚焦失敗狀態，執行聚焦 onShutterUp()： 如果是自動聚焦mode，并且為聚焦失敗狀態，執行取消聚焦 doSnap()：拍照 onTouch(MotionEvent e)：讓用戶可以取消掉之前未消失的觸摸聚焦 updateFocusUI()：聚焦框框顯示失敗

我是天王蓋地虎的分割線?????????????????????????????????????????????????????????????

總結

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