Android初级开发（八）——手机多媒体—弹窗选择照片或直接拍照的实现

一、效果图
实现的功能主要是主页一个Button,点击后弹出选择框，选择拍照还是从相册选取照片，不管哪种方式，最后将照片返回到主页面上显示出来。

二、实现
1、activity_main.xml布局

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="fill_parent"    android:layout_height="fill_parent"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >    <LinearLayout        android:id="@+id/btn_layout"        android:layout_width="fill_parent"        android:layout_height="wrap_content"        android:orientation="horizontal" >        <Button            android:id="@+id/btn"            android:layout_width="fill_parent"            android:layout_height="wrap_content"            android:layout_weight="1"            android:text="Choose picture" />    </LinearLayout>    <ImageView        android:id="@+id/img"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:layout_below="@+id/btn_layout" /></RelativeLayout>

2、创建一个图片的工具类，我这里用的是别人封装好的，如果以后对图片进行操作，可以直接调用
ImageTools.java

/** * Tools for handler picture * *  */public final class ImageTools {    /**     * Transfer drawable to bitmap     *      * @param drawable     * @return     */    public static Bitmap drawableToBitmap(Drawable drawable) {        int w = drawable.getIntrinsicWidth();        int h = drawable.getIntrinsicHeight();        Bitmap.Config config = drawable.getOpacity() != PixelFormat.OPAQUE ? Bitmap.Config.ARGB_8888                : Bitmap.Config.RGB_565;        Bitmap bitmap = Bitmap.createBitmap(w, h, config);        Canvas canvas = new Canvas(bitmap);        drawable.setBounds(0, 0, w, h);        drawable.draw(canvas);        return bitmap;    }    /**     * Bitmap to drawable     *      * @param bitmap     * @return     */    public static Drawable bitmapToDrawable(Bitmap bitmap) {        return new BitmapDrawable(bitmap);    }    /**     * Input stream to bitmap     *      * @param inputStream     * @return     * @throws Exception     */    public static Bitmap inputStreamToBitmap(InputStream inputStream)            throws Exception {        return BitmapFactory.decodeStream(inputStream);    }    /**     * Byte transfer to bitmap     *      * @param byteArray     * @return     */    public static Bitmap byteToBitmap(byte[] byteArray) {        if (byteArray.length != 0) {            return BitmapFactory                    .decodeByteArray(byteArray, 0, byteArray.length);        } else {            return null;        }    }    /**     * Byte transfer to drawable     *      * @param byteArray     * @return     */    public static Drawable byteToDrawable(byte[] byteArray) {        ByteArrayInputStream ins = null;        if (byteArray != null) {            ins = new ByteArrayInputStream(byteArray);        }        return Drawable.createFromStream(ins, null);    }    /**     * Bitmap transfer to bytes     *     * @return     */    public static byte[] bitmapToBytes(Bitmap bm) {        byte[] bytes = null;        if (bm != null) {            ByteArrayOutputStream baos = new ByteArrayOutputStream();            bm.compress(Bitmap.CompressFormat.PNG, 100, baos);            bytes = baos.toByteArray();        }        return bytes;    }    /**     * Drawable transfer to bytes     *      * @param drawable     * @return     */    public static byte[] drawableToBytes(Drawable drawable) {        BitmapDrawable bitmapDrawable = (BitmapDrawable) drawable;        Bitmap bitmap = bitmapDrawable.getBitmap();        byte[] bytes = bitmapToBytes(bitmap);        ;        return bytes;    }    /**     * Base64 to byte[]//   *///  public static byte[] base64ToBytes(String base64) throws IOException {//      byte[] bytes = Base64.decode(base64);//      return bytes;//  }////  /**//   * Byte[] to base64//   *///  public static String bytesTobase64(byte[] bytes) {//      String base64 = Base64.encode(bytes);//      return base64;//  }    /**     * Create reflection images     *      * @param bitmap     * @return     */    public static Bitmap createReflectionImageWithOrigin(Bitmap bitmap) {        final int reflectionGap = 4;        int w = bitmap.getWidth();        int h = bitmap.getHeight();        Matrix matrix = new Matrix();        matrix.preScale(1, -1);        Bitmap reflectionImage = Bitmap.createBitmap(bitmap, 0, h / 2, w,                h / 2, matrix, false);        Bitmap bitmapWithReflection = Bitmap.createBitmap(w, (h + h / 2),                Config.ARGB_8888);        Canvas canvas = new Canvas(bitmapWithReflection);        canvas.drawBitmap(bitmap, 0, 0, null);        Paint deafalutPaint = new Paint();        canvas.drawRect(0, h, w, h + reflectionGap, deafalutPaint);        canvas.drawBitmap(reflectionImage, 0, h + reflectionGap, null);        Paint paint = new Paint();        LinearGradient shader = new LinearGradient(0, bitmap.getHeight(), 0,                bitmapWithReflection.getHeight() + reflectionGap, 0x70ffffff,                0x00ffffff, TileMode.CLAMP);        paint.setShader(shader);        // Set the Transfer mode to be porter duff and destination in        paint.setXfermode(new PorterDuffXfermode(Mode.DST_IN));        // Draw a rectangle using the paint with our linear gradient        canvas.drawRect(0, h, w, bitmapWithReflection.getHeight()                + reflectionGap, paint);        return bitmapWithReflection;    }    /**     * Get rounded corner images     *      * @param bitmap     * @param roundPx     *            5 10     * @return     */    public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, float roundPx) {        int w = bitmap.getWidth();        int h = bitmap.getHeight();        Bitmap output = Bitmap.createBitmap(w, h, Config.ARGB_8888);        Canvas canvas = new Canvas(output);        final int color = 0xff424242;        final Paint paint = new Paint();        final Rect rect = new Rect(0, 0, w, h);        final RectF rectF = new RectF(rect);        paint.setAntiAlias(true);        canvas.drawARGB(0, 0, 0, 0);        paint.setColor(color);        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));        canvas.drawBitmap(bitmap, rect, rect, paint);        return output;    }    /**     * 缩小图片     *      * @param bitmap     * @param width     * @param height     * @return     */    public static Bitmap zoomBitmap(Bitmap bitmap, int width, int height) {        int w = bitmap.getWidth();        int h = bitmap.getHeight();        Matrix matrix = new Matrix();        float scaleWidth = ((float) width / w);        float scaleHeight = ((float) height / h);        matrix.postScale(scaleWidth, scaleHeight);        Bitmap newbmp = Bitmap.createBitmap(bitmap, 0, 0, w, h, matrix, true);        return newbmp;    }    /**     * Resize the drawable     * @param drawable     * @param w     * @param h     * @return     */    public static Drawable zoomDrawable(Drawable drawable, int w, int h) {        int width = drawable.getIntrinsicWidth();        int height = drawable.getIntrinsicHeight();        Bitmap oldbmp = drawableToBitmap(drawable);        Matrix matrix = new Matrix();        float sx = ((float) w / width);        float sy = ((float) h / height);        matrix.postScale(sx, sy);        Bitmap newbmp = Bitmap.createBitmap(oldbmp, 0, 0, width, height,                matrix, true);        return new BitmapDrawable(newbmp);    }    /**     * Get images from SD card by path and the name of image     * @param photoName     * @return     */    public static Bitmap getPhotoFromSDCard(String path,String photoName){        Bitmap photoBitmap = BitmapFactory.decodeFile(path + "/" +photoName +".png");        if (photoBitmap == null) {            return null;        }else {            return photoBitmap;        }    }    /**     * Check the SD card      * @return     */    public static boolean checkSDCardAvailable(){        return android.os.Environment.getExternalStorageState().equals(android.os.Environment.MEDIA_MOUNTED);    }    /**     * Get image from SD card by path and the name of image     * @return     */    public static boolean findPhotoFromSDCard(String path,String photoName){        boolean flag = false;        if (checkSDCardAvailable()) {            File dir = new File(path);            if (dir.exists()) {                File folders = new File(path);                File photoFile[] = folders.listFiles();                for (int i = 0; i < photoFile.length; i++) {                    String fileName = photoFile[i].getName().split("\\.")[0];                    if (fileName.equals(photoName)) {                        flag = true;                    }                }            }else {                flag = false;            }//          File file = new File(path + "/" + photoName  + ".jpg" );//          if (file.exists()) {//              flag = true;//          }else {//              flag = false;//          }        }else {            flag = false;        }        return flag;    }    /**     * 将图片保存到本地SD卡     * @param photoBitmap     * @param photoName     * @param path     */    public static void savePhotoToSDCard(Bitmap photoBitmap,String path,String photoName){        if (checkSDCardAvailable()) {            File dir = new File(path);            if (!dir.exists()){                dir.mkdirs();            }            File photoFile = new File(path , photoName + ".png");            FileOutputStream fileOutputStream = null;            try {                fileOutputStream = new FileOutputStream(photoFile);                if (photoBitmap != null) {                    if (photoBitmap.compress(Bitmap.CompressFormat.PNG, 100, fileOutputStream)) {                        fileOutputStream.flush();//                      fileOutputStream.close();                    }                }            } catch (FileNotFoundException e) {                photoFile.delete();                e.printStackTrace();            } catch (IOException e) {                photoFile.delete();                e.printStackTrace();            } finally{                try {                    fileOutputStream.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }     }    /**     * Delete the image from SD card     * @param path     * file:///sdcard/temp.jpg     */    public static void deleteAllPhoto(String path){        if (checkSDCardAvailable()) {            File folder = new File(path);            File[] files = folder.listFiles();            for (int i = 0; i < files.length; i++) {                files[i].delete();            }        }    }    //删除上一次截图的临时文件，包括图片路径和文件名称    public static void deletePhotoAtPathAndName(String path,String fileName){        if (checkSDCardAvailable()) {            File folder = new File(path);            File[] files = folder.listFiles();            for (int i = 0; i < files.length; i++) {                System.out.println(files[i].getName());                if (files[i].getName().equals(fileName)) {                    files[i].delete();                }            }        }    }}

3、MainActivity.java

public class MainActivity extends Activity {    private static final int TAKE_PICTURE = 0;  //拍照    private static final int CHOOSE_PICTURE = 1;  //从相册中选择照片    private static final int CROP = 2;    private static final int CROP_PICTURE = 3;    private static final int SCALE = 5;//照片缩小比例    private ImageView iv_image = null;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        iv_image = (ImageView) this.findViewById(R.id.img);        this.findViewById(R.id.btn).setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                //弹出对话框，选择要直接拍照还是从相册中选择照片                showPicturePicker(MainActivity.this,false);            }        });    }    //弹出Dialog选择窗口    public void showPicturePicker(Context context,boolean isCrop){        final boolean crop = isCrop;        AlertDialog.Builder builder = new AlertDialog.Builder(context);        //设置弹出框标题        builder.setTitle("图片来源");        builder.setNegativeButton("取消", null);        builder.setItems(new String[]{"拍照","相册"}, new DialogInterface.OnClickListener() {            //类型码            int REQUEST_CODE;            @Override            public void onClick(DialogInterface dialog, int which) {                switch (which) {                case TAKE_PICTURE:                    Uri imageUri = null;                    String fileName = null;                    //发送启动相机程序请求                    Intent openCameraIntent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);                    if (crop) {                        REQUEST_CODE = CROP;                        //删除上一次截图的临时文件                        SharedPreferences sharedPreferences = getSharedPreferences("temp",Context.MODE_WORLD_WRITEABLE);                        ImageTools.deletePhotoAtPathAndName(Environment.getExternalStorageDirectory().getAbsolutePath(), sharedPreferences.getString("tempName", ""));                        //保存本次截图临时文件名字                        fileName = String.valueOf(System.currentTimeMillis()) + ".jpg";                        Editor editor = sharedPreferences.edit();                        editor.putString("tempName", fileName);                        editor.commit();                    }else {                        REQUEST_CODE = TAKE_PICTURE;                        fileName = "image.jpg";                    }                    //从文件中创建URI                    imageUri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(),fileName));                    //指定照片保存路径（SD卡），image.jpg为一个临时文件，每次拍照后这个图片都会被替换                    openCameraIntent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri);                    //开启一个带有返回值的Activity，请求吗为REQUEST_CODE                    startActivityForResult(openCameraIntent, REQUEST_CODE);                    break;                case CHOOSE_PICTURE:                    //发送打开相册程序器请求                    Intent openAlbumIntent = new Intent(Intent.ACTION_GET_CONTENT);                    if (crop) {                        REQUEST_CODE = CROP;                    }else {                        REQUEST_CODE = CHOOSE_PICTURE;                    }                    openAlbumIntent.setDataAndType(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, "image/*");                    startActivityForResult(openAlbumIntent, REQUEST_CODE);                    break;                default:                    break;                }            }        });        builder.create().show();    }    //截取图片    public void cropImage(Uri uri, int outputX, int outputY, int requestCode){        Intent intent = new Intent("com.android.camera.action.CROP");          intent.setDataAndType(uri, "image/*");          intent.putExtra("crop", "true");          intent.putExtra("aspectX", 1);          intent.putExtra("aspectY", 1);          intent.putExtra("outputX", outputX);           intent.putExtra("outputY", outputY);         intent.putExtra("outputFormat", "JPEG");        intent.putExtra("noFaceDetection", true);        intent.putExtra("return-data", true);          startActivityForResult(intent, requestCode);    }    @Override    protected void onActivityResult(int requestCode, int resultCode, Intent data) {        super.onActivityResult(requestCode, resultCode, data);        if (resultCode == RESULT_OK) {            switch (requestCode) {                case TAKE_PICTURE:                    //将保存在本地的图片取出并缩小后显示在界面上                    Bitmap bitmap = BitmapFactory.decodeFile(Environment.getExternalStorageDirectory()+"/image.jpg");                    Bitmap newBitmap = ImageTools.zoomBitmap(bitmap, bitmap.getWidth() / SCALE, bitmap.getHeight() / SCALE);                    //由于Bitmap内存占用较大，这里需要回收内存，否则会报out of memory异常                    bitmap.recycle();                    //将处理过的图片显示在界面上，并保存到本地                    iv_image.setImageBitmap(newBitmap);                    ImageTools.savePhotoToSDCard(newBitmap, Environment.getExternalStorageDirectory().getAbsolutePath(), String.valueOf(System.currentTimeMillis()));                    break;                case CHOOSE_PICTURE:                    ContentResolver resolver = getContentResolver();                    //照片的原始资源地址                    Uri originalUri = data.getData();                    try {                        //使用ContentProvider通过URI获取原始图片                        Bitmap photo = MediaStore.Images.Media.getBitmap(resolver, originalUri);                        if (photo != null) {                            //为防止原始图片过大导致内存溢出，这里先缩小原图显示，然后释放原始Bitmap占用的内存                            Bitmap smallBitmap = ImageTools.zoomBitmap(photo, photo.getWidth() / SCALE, photo.getHeight() / SCALE);                            //释放原始图片占用的内存，防止out of memory异常发生                            photo.recycle();                            iv_image.setImageBitmap(smallBitmap);                        }                    } catch (FileNotFoundException e) {                        e.printStackTrace();                    } catch (IOException e) {                        e.printStackTrace();                    }                    break;                case CROP:                    Uri uri = null;                    if (data != null) {                        uri = data.getData();                        System.out.println("Data");                    }else {                        System.out.println("File");                        String fileName = getSharedPreferences("temp",Context.MODE_WORLD_WRITEABLE).getString("tempName", "");                        uri = Uri.fromFile(new File(Environment.getExternalStorageDirectory(),fileName));                    }                    cropImage(uri, 500, 500, CROP_PICTURE);                    break;                case CROP_PICTURE:                    Bitmap photo = null;                    Uri photoUri = data.getData();                    if (photoUri != null) {                        photo = BitmapFactory.decodeFile(photoUri.getPath());                    }                    if (photo == null) {                        Bundle extra = data.getExtras();                        if (extra != null) {                            photo = (Bitmap)extra.get("data");                            ByteArrayOutputStream stream = new ByteArrayOutputStream();                            photo.compress(Bitmap.CompressFormat.JPEG, 100, stream);                        }                    }                    iv_image.setImageBitmap(photo);                    break;                default:                    break;            }        }    }}

4、修改AndroidManifest.xml

<manifest xmlns:android="http://schemas.android.com/apk/res/android"    package="com.ryantang.picture"    android:versionCode="1"    android:versionName="1.0" >    <uses-sdk        android:minSdkVersion="8"        android:targetSdkVersion="17" />    <uses-feature android:name="android.hardware.camera" />    <uses-feature android:name="android.hardware.camera.autofocus" />    <uses-permission android:name="android.permission.CAMERA" />    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />    <application        android:allowBackup="true"        android:icon="@drawable/ic_launcher"        android:label="@string/app_name"        android:theme="@style/AppTheme" >        <activity            android:name="com.ryantang.picture.MainActivity"            android:label="@string/app_name" >            <intent-filter>                <action android:name="android.intent.action.MAIN" />                <category android:name="android.intent.category.LAUNCHER" />            </intent-filter>        </activity>    </application></manifest>

上面的代码是借鉴别人的，我之前没考虑到用Dialog。之前做的是仿微信的底部弹窗，用的是popupwindow，遇到的问题是我们创建了一个popupwindow活动，在活动中监听按钮进入图片或者相机，这样最后得到的图片返回到popupwindow，并没有传到MainActivity。我尝试过将图片bitmap传到MainActivity，或者图片URI传过去，也尝试用startActivityForResult传值，都没有成功，，，问题可能还是对于三个问题理解不深入：1、对于文件存储和读取的理解；2、对于一个Activity传值给另一个Activity，或者说一个Activity控制另一个Activity的UI更新；3、对与startActivityForResult和onActivityResult的理解。。。。继续努力吧！！！