/**
* A single preview frame will be returned to the handler supplied. The data will arrive as byte[]
* in the message.obj field, with width and height encoded as message.arg1 and message.arg2,
* respectively.
*
* @param handler The handler to send the message to.
* @param message The what field of the message to be sent.
*/
public void requestPreviewFrame(Handler handler, int message) {
Camera theCamera = camera;
if (theCamera != null && previewing) {
previewCallback.setHandler(handler, message);
theCamera.setOneShotPreviewCallback(previewCallback);
}
}
/**
* A single preview frame will be returned to the handler supplied. The data will arrive as byte[]
* in the message.obj field, with width and height encoded as message.arg1 and message.arg2,
* respectively.
*
* @param handler The handler to send the message to.
* @param message The what field of the message to be sent.
*/
public synchronized void requestOcrDecode(Handler handler, int message) {
Camera theCamera = camera;
if (theCamera != null && previewing) {
previewCallback.setHandler(handler, message);
theCamera.setOneShotPreviewCallback(previewCallback);
}
}
/**
* executes <br>
* <code>camera.setOneShotPreviewCallback(callback)</code> if <br>
* <code>camera != null</code>
*
* @param callback callback to provide
*/
public synchronized void requestNextFrame(Camera.PreviewCallback callback) {
try {
if (camera != null) {
camera.setOneShotPreviewCallback(callback);
}
} catch (Exception e) {
}
}
/**
* A single preview frame will be returned to the handler supplied. The data will arrive as byte[]
* in the message.obj field, with width and height encoded as message.arg1 and message.arg2,
* respectively. <br>
* 两个绑定操作：<br>
* 1：将handler与回调函数绑定；<br>
* 2：将相机与回调函数绑定<br>
* 综上，该函数的作用是当相机的预览界面准备就绪后就会调用hander向其发送传入的message
*
* @param handler The handler to send the message to.
* @param message The what field of the message to be sent.
*/
public synchronized void requestPreviewFrame(Handler handler, int message) {
Camera theCamera = camera;
if (theCamera != null && previewing) {
previewCallback.setHandler(handler, message);
// 绑定相机回调函数，当预览界面准备就绪后会回调Camera.PreviewCallback.onPreviewFrame
theCamera.setOneShotPreviewCallback(previewCallback);
}
}
/**
* A single preview frame will be returned to the handler supplied. The data will arrive as byte[]
* in the message.obj field, with width and height encoded as message.arg1 and message.arg2,
* respectively.
*
* @param handler The handler to send the message to.
* @param message The what field of the message to be sent.
*/
public void requestPreviewFrame(Handler handler, int message) {
if (camera != null && previewing) {
previewCallback.setHandler(handler, message);
if (useOneShotPreviewCallback) {
camera.setOneShotPreviewCallback(previewCallback);
} else {
camera.setPreviewCallback(previewCallback);
}
}
}
public void stopCameraPreview() {
if (mCamera != null) {
try {
mPreviewing = false;
mCamera.cancelAutoFocus();
mCamera.setOneShotPreviewCallback(null);
mCamera.stopPreview();
} catch (Exception e) {
Log.e(TAG, e.toString(), e);
}
}
}
public void showCameraPreview() {
if (mCamera != null) {
try {
mPreviewing = true;
setupCameraParameters();
mCamera.setPreviewDisplay(getHolder());
mCamera.setDisplayOrientation(getDisplayOrientation());
mCamera.setOneShotPreviewCallback(mPreviewCallback);
mCamera.startPreview();
if (mAutoFocus) {
if (mSurfaceCreated) { // check if surface created before using autofocus
safeAutoFocus();
} else {
scheduleAutoFocus(); // wait 1 sec and then do check again
}
}
} catch (Exception e) {
Log.e(TAG, e.toString(), e);
}
}
}
public void setOneShotPreviewCallback(PreviewCallback callback) {
if (camera != null) {
camera.setOneShotPreviewCallback(callback);
}
}
public void requestPreviewFrame(final PreviewCallback callback) {
camera.setOneShotPreviewCallback(callback);
}
@Override
public void setOneShotPreviewCallback(Camera.PreviewCallback cb) {
camera.setOneShotPreviewCallback(cb);
}