拍照（二）得到全尺寸图片，并进行压缩

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <Button
        android:id="@+id/take_photo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="Take Photo" />

    <Button
        android:id="@+id/get_photo"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:text="get Photo" />

    <ImageView
        android:id="@+id/picture"
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:layout_gravity="center_horizontal" />

</LinearLayout>

 

package com.example.choosepictest;

import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.Date;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity implements OnClickListener {

    static final int REQUEST_IMAGE_CAPTURE = 1;


    private Button takePhoto;
    private Button getPhoto;
    private ImageView picture;
    private Uri imgUri;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        takePhoto = (Button) findViewById(R.id.take_photo);
        getPhoto = (Button) findViewById(R.id.get_photo);
        picture = (ImageView) findViewById(R.id.picture);
        takePhoto.setOnClickListener(this);
        getPhoto.setOnClickListener(this);

    }    

    @Override
    public void onClick(View v) {
        switch (v.getId()) {
        case R.id.take_photo:
            dispatchTakePictureIntent();
            break;
        
        default:
            break;
        }

    }
    
    // 保存全尺寸照片
    String mCurrentPhotoPath;
    private void dispatchTakePictureIntent() {
        
        File appDir = new File(Environment.getExternalStorageDirectory(),
                "/etoury/picCache");
        if (!appDir.exists()) {
         appDir.mkdirs();
        }
        String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
                .format(new Date());
        String fileName = timeStamp + ".jpg";
        
        File outputImage = new File(appDir, fileName);
        try {
            if (outputImage.exists()) {
                outputImage.delete();
            }
            outputImage.createNewFile();
        } catch (IOException e) {
            e.printStackTrace();
        }
        mCurrentPhotoPath = outputImage.getAbsolutePath();
        imgUri = Uri.fromFile(outputImage);
        // 意图 相机
        Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
        intent.putExtra(MediaStore.EXTRA_OUTPUT, imgUri);
        // 如果有相机
        if (intent.resolveActivity(getPackageManager()) != null) {
            startActivityForResult(intent, REQUEST_IMAGE_CAPTURE);
        }
    }
    
    //解码缩放图片(Decode a Scaled Image)
    private void setPic() {
        // Get the dimensions of the View
        int targetW = picture.getWidth();
        int targetH = picture.getHeight();
        // Get the dimensions of the bitmap
        BitmapFactory.Options bmOptions = new BitmapFactory.Options();
        // 该 值设为true那么将不返回实际的bitmap，也不给其分配内存空间这样就避免内存溢出了。但是允许我们查询图片的信息这其中就包括图片大小信息
        bmOptions.inJustDecodeBounds = true;
        BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
        int photoW = bmOptions.outWidth;
        int photoH = bmOptions.outHeight;
        // Determine how much to scale down the image
        // Math.min求最小值
        int scaleFactor = Math.min(photoW/targetW, photoH/targetH);
        // Decode the image file into a Bitmap sized to fill the View
        bmOptions.inJustDecodeBounds = false;
        // 设置恰当的inSampleSize可以使BitmapFactory分配更少的空间以消除该错误
        bmOptions.inSampleSize = scaleFactor;
        // 如果inPurgeable设为True的话表示使用BitmapFactory创建的Bitmap,用于存储Pixel的内存空间在系统内存不足时可以被回收
        bmOptions.inPurgeable = true;
        Bitmap bitmap = BitmapFactory.decodeFile(mCurrentPhotoPath, bmOptions);
        picture.setImageBitmap(bitmap);
    }
    
    @Override
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        if (resultCode == RESULT_OK) {
            switch (requestCode) {


            case REQUEST_IMAGE_CAPTURE:
            galleryAddPic();
                setPic();
                break;


            default:
                break;
            }
        }
    }
    //发送一条通知添加照片到相册
    private void galleryAddPic() {
        
        Intent mediaScanIntent = new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE);

        mediaScanIntent.setData(imgUri);
        this.sendBroadcast(mediaScanIntent);
        }

}