android - 将自动对焦放在android相机类中的位置

Question

我正在尝试使用自动对焦我不知道将自动对焦放在哪里有人知道如何实现自动对焦吗？

------------预习类------------

 package com.marakana;

 import java.io.IOException;

 import android.content.Context;
 import android.hardware.Camera;
 import android.hardware.Camera.PreviewCallback;
 import android.util.Log;
 import android.view.SurfaceHolder;
 import android.view.SurfaceView;

class Preview extends SurfaceView implements SurfaceHolder.Callback { // <1>
private static final String TAG = "Preview";

SurfaceHolder mHolder;  // <2>
public Camera camera; // <3>

Preview(Context context) {
super(context);

// Install a SurfaceHolder.Callback so we get notified when the
// underlying surface is created and destroyed.
mHolder = getHolder();  // <4>
mHolder.addCallback(this);  // <5>
mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); // <6>
}

 // Called once the holder is ready
public void surfaceCreated(SurfaceHolder holder) {  // <7>
// The Surface has been created, acquire the camera and tell it where
// to draw.
camera = Camera.open(); // <8>
try {
  camera.setPreviewDisplay(holder);  // <9>

  camera.setPreviewCallback(new PreviewCallback() { // <10>
    // Called for each frame previewed
    public void onPreviewFrame(byte[] data, Camera camera) {  // <11>
      Log.d(TAG, "onPreviewFrame called at: " + System.currentTimeMillis());
      Preview.this.invalidate();  // <12>
     }
   });
 } catch (IOException e) { // <13>
  e.printStackTrace();
   }
  }

 // Called when the holder is destroyed
public void surfaceDestroyed(SurfaceHolder holder) {  // <14>
camera.stopPreview();
camera = null;
}

// Called when holder has changed
public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { // <15>
  camera.startPreview();
 }

}

----------------相机 Activity ------------------------

preview = new Preview(this); // <3>
((FrameLayout) findViewById(R.id.preview)).addView(preview); // <4>

buttonClick = (Button) findViewById(R.id.buttonClick);
buttonClick.setOnClickListener(new OnClickListener() {
  public void onClick(View v) { // <5>

      preview.camera.takePicture(shutterCallback, rawCallback, jpegCallback);
  }
});

// Handles data for jpeg picture
PictureCallback jpegCallback = new PictureCallback() { // <8>
public void onPictureTaken(byte[] data, Camera camera) {
  FileOutputStream outStream = null;
  try {
    // Write to SD Card

    outStream = new FileOutputStream(imgPath); // <9>
    outStream.write(data);
    outStream.close();
    intImg = new Intent(CameraActivity.this, DisplayImg.class);
    intImg.putExtra("imgPath",imgPath);
    startActivity(intImg);
    Log.d(TAG, "onPictureTaken - wrote bytes: " + data.length);
  } catch (FileNotFoundException e) { // <10>
    e.printStackTrace();
  } catch (IOException e) {
    e.printStackTrace();
  } finally {
  }
  Log.d(TAG, "onPictureTaken - jpeg");
}
};

Answer 1

如果你设置了自动对焦，你应该这样做:

camera.autoFocus(new AutoFocusCallback() {
        @Override
        public void onAutoFocus(boolean success, Camera camera) {
            if(success){
                camera.takePicture(shutterCallback, rawCallback, jpegCallback);
            }
        }
    });

这就是相机等待自动对焦的方式;)