我终于解决了这个问题。下面是一些代码,供想要了解如何截取布局屏幕截图、从相机获取图片(无需意图)、在SurfaceView内容上进行截屏(类似于)并将截屏保存到文件夹中的人参考:
public class Cam_View extends Activity implements SurfaceHolder.Callback {
protected static final int CAPTURE_IMAGE_ACTIVITY_REQUEST_CODE = 0;
private SurfaceView SurView;
private SurfaceHolder camHolder;
private boolean previewRunning;
final Context context = this;
public static Camera camera = null;
private RelativeLayout CamView;
private Bitmap inputBMP = null, bmp, bmp1;
private ImageView mImage;
@SuppressWarnings("deprecation")
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.camera);
CamView = (RelativeLayout) findViewById(R.id.camview);
SurView = (SurfaceView)findViewById(R.id.sview);
camHolder = SurView.getHolder();
camHolder.addCallback(this);
camHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
camera_image = (ImageView) findViewById(R.id.camera_image);
Button btn = (Button) findViewById(R.id.button1);
btn.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
camera.takePicture(null, null, mPicture);
}
});
}
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,//NEEDED FOR THE PREVIEW
int height) {
if(previewRunning) {
camera.stopPreview();
}
Camera.Parameters camParams = camera.getParameters();
Camera.Size size = camParams.getSupportedPreviewSizes().get(0);
camParams.setPreviewSize(size.width, size.height);
camera.setParameters(camParams);
try {
camera.setPreviewDisplay(holder);
camera.startPreview();
previewRunning=true;
} catch(IOException e) {
e.printStackTrace();
}
}
public void surfaceCreated(SurfaceHolder holder) {
try {
camera=Camera.open();
} catch(Exception e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
finish();
}
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
camera.stopPreview();
camera.release();
camera=null;
}
public void TakeScreenshot(){
Random num = new Random();
int nu=num.nextInt(1000);
CamView.setDrawingCacheEnabled(true);
CamView.buildDrawingCache(true);
Bitmap bmp = Bitmap.createBitmap(CamView.getDrawingCache());
CamView.setDrawingCacheEnabled(false);
ByteArrayOutputStream bos = new ByteArrayOutputStream();
bmp.compress(CompressFormat.JPEG, 100, bos);
byte[] bitmapdata = bos.toByteArray();
ByteArrayInputStream fis = new ByteArrayInputStream(bitmapdata);
String picId=String.valueOf(nu);
String myfile="Ghost"+picId+".jpeg";
File dir_image = new File(Environment.getExternalStorageDirectory()+
File.separator+"Ultimate Entity Detector");
dir_image.mkdirs();
try {
File tmpFile = new File(dir_image,myfile);
FileOutputStream fos = new FileOutputStream(tmpFile);
byte[] buf = new byte[1024];
int len;
while ((len = fis.read(buf)) > 0) {
fos.write(buf, 0, len);
}
fis.close();
fos.close();
Toast.makeText(getApplicationContext(),
"The file is saved at :SD/Ultimate Entity Detector",Toast.LENGTH_LONG).show();
bmp1 = null;
camera_image.setImageBitmap(bmp1);
camera.startPreview();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
private PictureCallback mPicture = new PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
File dir_image2 = new File(Environment.getExternalStorageDirectory()+
File.separator+"Ultimate Entity Detector");
dir_image2.mkdirs();
File tmpFile = new File(dir_image2,"TempGhost.jpg");
try {
FileOutputStream fos = new FileOutputStream(tmpFile);
fos.write(data);
fos.close();
} catch (FileNotFoundException e) {
Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
} catch (IOException e) {
Toast.makeText(getApplicationContext(),"Error",Toast.LENGTH_LONG).show();
}
String path = (Environment.getExternalStorageDirectory()+
File.separator+"Ultimate EntityDetector"+
File.separator+"TempGhost.jpg");
BitmapFactory.Options options = new BitmapFactory.Options();
options.inPreferredConfig = Bitmap.Config.ARGB_8888;
bmp1 = BitmapFactory.decodeFile(path, options);
camera_image.setImageBitmap(bmp1);
tmpFile.delete();
TakeScreenshot();
}
};
public Bitmap decodeFile(File f) {
Bitmap b = null;
try {
BitmapFactory.Options o = new BitmapFactory.Options();
o.inJustDecodeBounds = true;
FileInputStream fis = new FileInputStream(f);
BitmapFactory.decodeStream(fis, null, o);
fis.close();
int IMAGE_MAX_SIZE = 1000;
int scale = 1;
if (o.outHeight > IMAGE_MAX_SIZE || o.outWidth > IMAGE_MAX_SIZE) {
scale = (int) Math.pow(
2,
(int) Math.round(Math.log(IMAGE_MAX_SIZE
/ (double) Math.max(o.outHeight, o.outWidth))
/ Math.log(0.5)));
}
BitmapFactory.Options o2 = new BitmapFactory.Options();
o2.inSampleSize = scale;
fis = new FileInputStream(f);
b = BitmapFactory.decodeStream(fis, null, o2);
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
return b;
}
}
如果您想要简单地截屏(不需要摄像头),则可以仅使用TakeScreenshot方法。
如果您想要对SurfaceView进行截屏,但直接从SurfaceView上无法实现,则使用mPicture,将捕获的图片设置为背景,然后调用TakeScreenshot来截屏。(如上所示)
如果您想要使用相机拍照而无需调用其他相机应用程序,则使用上面代码中的takePicture、mPicture和SurfaceView。
如果按原样使用上述代码,则会截取布局内容(按钮、图像视图等)并将相机中的图像设置为背景。
下面还提供了用于上述代码的基本布局XML:
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/camview">
<SurfaceView
android:id="@+id/sview"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
<ImageView
android:id="@+id/camera_image"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:contentDescription="@string/app_name" />
<Button
android:id="@+id/button1"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />
</RelativeLayout>
不要忘记导入需要导入的内容。