Ricordarsi di aggiungere su manifest le seguenti righe per abilitare l'uso della fotocamera:
<uses-permission android:name="android.permission.CAMERA" />
<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />
CE_Fake_Reveal.java :
package com.example.marco.cefakereveal;
import java.io.IOException;
import android.app.Activity;
import android.content.pm.ActivityInfo;
import android.graphics.PixelFormat;
import android.hardware.Camera;
import android.os.Bundle;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.graphics.Matrix;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.widget.ImageView;
import android.widget.TextView;
public class CE_Fake_Reveal extends Activity implements SurfaceHolder.Callback{
ImageView img;
private Matrix matrix = new Matrix();
private float scale = 0.2f;
private ScaleGestureDetector SGD;
Camera camera;
SurfaceView surfaceView;
SurfaceHolder surfaceHolder;
boolean previewing = false;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_ce__fake__reveal);
setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
img = (ImageView)findViewById(R.id.imageView1);
getWindow().setFormat(PixelFormat.UNKNOWN);
surfaceView = (SurfaceView)findViewById(R.id.camerapreview);
surfaceHolder = surfaceView.getHolder();
surfaceHolder.addCallback(this);
SGD = new ScaleGestureDetector(this,new ScaleListener());
scale = 1.0f;
img.addOnLayoutChangeListener(new View.OnLayoutChangeListener() {
@Override
public void onLayoutChange(View v, int left, int top, int right, int bottom, int oldLeft, int oldTop, int oldRight, int oldBottom)
{
updateScale();
}
});
}
@Override
public boolean onTouchEvent(MotionEvent ev) {
SGD.onTouchEvent(ev);
return true;
}
void updateScale()
{
final float imageWidth = (float)img.getDrawable().getIntrinsicWidth();
final float imageHeight = (float)img.getDrawable().getIntrinsicHeight();
float frameHeight = img.getHeight();
float frameWidth = img.getWidth();
matrix.reset();
matrix.postTranslate(-imageWidth / 2.0f, -imageHeight / 2.0f);
matrix.postScale(scale, scale);
matrix.postTranslate(frameWidth / 2.0f, frameHeight / 2.0f );
img.setImageMatrix(matrix);
}
private class ScaleListener extends ScaleGestureDetector.
SimpleOnScaleGestureListener {
@Override
public boolean onScale(ScaleGestureDetector detector) {
scale *= detector.getScaleFactor();
scale = Math.max(0.03f, Math.min(scale, 0.5f));
updateScale();
return true;
}
}
/* *************************************************/
/* Ora inizia il codice che riguarda la fotocamera */
/* *************************************************/
@Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
if(previewing){
camera.stopPreview();
previewing = false;
}
if (camera != null){
try {
camera.setPreviewDisplay(surfaceHolder);
Camera.Parameters parameters = camera.getParameters();
parameters.setFocusMode(Camera.Parameters.FOCUS_MODE_CONTINUOUS_PICTURE);
camera.setParameters(parameters);
camera.startPreview();
previewing = true;
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
@Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
camera = Camera.open();
}
@Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
camera.stopPreview();
camera.release();
camera = null;
previewing = false;
}
}
activity_ce_fake_reveal.xml :
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:weightSum="1">
<SurfaceView
android:id="@+id/camerapreview"
android:layout_width="fill_parent"
android:layout_height="fill_parent" />
<ImageView
android:id="@+id/imageView1"
android:scaleType="matrix"
android:layout_height="fill_parent"
android:layout_width="fill_parent"
android:src="@drawable/ce"
android:layout_centerInParent="true"
android:alpha="0.4" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Confrontare la scritta CE per verificarne la validità"
android:id="@+id/textView"
android:textStyle="bold"
android:textColor="#fffdff12"
android:layout_alignParentTop="true"
android:textAlignment="center"
android:layout_centerHorizontal="true" />
</RelativeLayout>
