【发布时间】:2014-11-17 12:21:57
【问题描述】:
我需要将手机的摄像头用于应用程序,但我是一名新程序员,在任何地方都找不到提供完整答案的网站。
这是我的主要活动:
公共类 MainActivity 扩展 Activity {
private Camera cameraObject;
private ShowCamera showCamera;
public static Camera isCameraAvailiable(){
Camera object = null;
try {
object = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return object; // returns null if camera is unavailable
}
private PictureCallback capturedIt = new PictureCallback() {
@Override
public void onPictureTaken(byte[] data, Camera camera) {
Bitmap bitmap = BitmapFactory.decodeByteArray(data , 0, data .length);
if(bitmap==null){
Toast.makeText(getApplicationContext(), "not taken", Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(), "taken", Toast.LENGTH_SHORT).show();
}
cameraObject.release();
}
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cameraObject = isCameraAvailiable();
showCamera = new ShowCamera(this, cameraObject);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(showCamera);
}
public void snapIt(View view){
cameraObject.takePicture(null, null, capturedIt);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
【问题讨论】:
-
您可以运行一个循环,在一定时间后多次调用
cameraObject.takePicture(null, null, capturedIt);。 -
或者,您可以为您的
showCamera对象使用触摸处理程序,该对象在内部调用您的snapIt方法。 -
如果我有另一个按钮,如果我想拍一张新照片,你能给出更详细的答案吗?它会重新开始整个过程。