安卓中关于相机的一些知识点

代码块

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);

Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
Uri uri = Uri.fromFile(new File(path));
intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
startActivityForResult(intent, Photo_Big);

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {

super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == Photo_Small) {
Bundle bundle = data.getExtras();
Bitmap bitmap = (Bitmap) bundle.get("data");
iv.setImageBitmap(bitmap);

}
if (requestCode == Photo_Big) {
FileInputStream is = null;
try {
is = new FileInputStream(path);
Bitmap bitmap = BitmapFactory.decodeStream(is);
iv.setImageBitmap(bitmap);
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
}
}

自定义相机

<?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:orientation="vertical" >

<SurfaceView
android:id="@+id/sfv"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:layout_alignParentLeft="true"
android:layout_alignParentTop="true" />

<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:onClick="Click"
android:text="Click!"
android:layout_alignParentBottom="true"/>

</RelativeLayout>

public class mCamera extends Activity implements SurfaceHolder.Callback {

private Camera mCamera;
private SurfaceView preview;
private SurfaceHolder mholder;

@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.camera);
preview = (SurfaceView) findViewById(R.id.sfv);
mholder = preview.getHolder();
mholder.addCallback(this);
}

@Override
protected void onResume() {
super.onResume();
if (mCamera == null) {
mCamera = GetCamera();
if (mholder != null) {
StartPreview(mCamera, mholder);
}
}
}

@Override
protected void onPause() {
super.onPause();
ReleaseCamera();
}

public void Click(View v) {

}

// 获取硬件相机资源
private Camera GetCamera() {
Camera camera = Camera.open();
return camera;
}

// 开启预览
private void StartPreview(Camera camera, SurfaceHolder holder) {
try {
camera.setPreviewDisplay(holder);
camera.setDisplayOrientation(90);
camera.startPreview();
} catch (IOException e) {
e.printStackTrace();
}
}

// 释放硬件相机资源
private void ReleaseCamera() {
if (mCamera != null) {
mCamera.setPreviewCallback(null);
mCamera.stopPreview();
mCamera.release();
mCamera = null;
}
}

/* 重写方法 */
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
StartPreview(mCamera, mholder);
}

@Override
public void surfaceCreated(SurfaceHolder holder) {
mCamera.stopPreview();
StartPreview(mCamera, mholder);
}

@Override
public void surfaceDestroyed(SurfaceHolder holder) {
ReleaseCamera();
}
/* 重写方法 */
}

<intent-filter >
<action android:name="android.media.action.IMAGE_CAPTURE"/>

<category android:name="android.intent.category.DEFAULT"/>
</intent-filte`
>

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>
<uses-permission android:name="android.permission.CAMERA"/>