android - 如何保存在android ImageView中显示的图像？

Question

我的要求是，

1. 为可绘制文件夹加载图像，然后在图像周围添加圆角。
2. 在图像周围填充白色/绿色描边。

我在这里完成了它们，这里我的问题是，当我存储显示在 ImageView 中的图像时，它没有存储。

对于圆角，我使用了下面的代码。

   private BitmapDrawable roundCornered(BitmapDrawable scaledBitmap, int i) {

        Bitmap bitmap = scaledBitmap.getBitmap();

        result = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(),
                Bitmap.Config.ARGB_8888);
        canvas = new Canvas(result);

        color = 0xff424242;
        paint = new Paint();
        rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        rectF = new RectF(rect);
        roundPx = i;
        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);

               //Add Stroke code Snippet here

        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        BitmapDrawable finalresult = new BitmapDrawable(result);
        saveImage_Rotate_white(finalresult.getBitmap());
        return finalresult;
    }

在我的 ma​​in.xml 中:

     <?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/finalLayout"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:background="@android:color/black"
    android:orientation="vertical" >

    <ImageView
        android:id="@+id/imageView1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerHorizontal="true"
        android:layout_centerVertical="true"
        android:background="@drawable/roundcorner"
        android:src="@drawable/test" />

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentLeft="true"
        android:layout_centerVertical="true"
        android:layout_marginLeft="20dp"
        android:text="Click here to Rotate" />

</RelativeLayout>

要使 ImageView 成为圆边，

<shape xmlns:android="http://schemas.android.com/apk/res/android" >

    <stroke
        android:width="6dp"
        android:color="#FFFFFF" />

    <padding
        android:bottom="3dp"
        android:left="3dp"
        android:right="3dp"
        android:top="3dp" />

    <corners android:radius="12dp" />

</shape>

代码的最终结果如下所示

在这里，我必须将此图像保存在我的 SdCard 中。我怎样才能做到这一点。我尝试在 roundCornered() 方法中使用以下代码 fragment ，而不是 xml。这也行不通。

          // for stroke

     final Rect rect1 = new Rect((rect.left - 10), (rect.top - 10),
     (rect.right + 10), (rect.bottom + 10));
     final RectF rectF1 = new RectF(rect1);

     Paint p = new Paint();
     p.setStrokeWidth(1.0f);
     p.setColor(Color.GREEN);
     p.setStyle(Style.STROKE);
     paint.setXfermode(new PorterDuffXfermode(Mode.SRC_OUT));
     canvas.drawRoundRect(rectF1, 12, 12, p);

我的整个 Activity 是，

public class BorderDraw extends Activity {
    ImageView rec_image;
    String rec_path;
    RelativeLayout mLayout;
    private Bitmap result;
    private int color;
    private Paint paint;
    private Rect rect;
    private RectF rectF;
    private Canvas canvas;
    private float roundPx;
    RelativeLayout innerLayout;
    static File rotated_File, bordered_file;
    Button b1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        // TODO Auto-generated method stub
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
        b1 = (Button) findViewById(R.id.button1);
        b1.setVisibility(View.GONE);
        mLayout = (RelativeLayout) findViewById(R.id.finalLayout);
        rec_image = (ImageView) findViewById(R.id.imageView1);
        rec_path = getIntent().getExtras().getString("image_file");
        Log.v("Image Path", rec_path);
        // rec_image.setDrawingCacheEnabled(true);
        String fname = "RoundCorner.jpg";
        rotated_File = new File("/sdcard/" + fname);
        bordered_file = new File("/sdcard/cornered_image.png");
        BitmapDrawable scaledBitmap = resizeBitmap(rec_path, 200, 200,
                rec_image);

        BitmapDrawable cornered_bitmap = roundCornered(scaledBitmap, 12);

        // saveImage_Rotate_white(cornered_bitmap.getBitmap());
        rec_image.setImageDrawable(cornered_bitmap);

        System.out.println("ImageView Height" + rec_image.getHeight());
        System.out.println("ImageView Width" + rec_image.getWidth());

    }

    private BitmapDrawable roundCornered(BitmapDrawable scaledBitmap, int i) {

        Bitmap bitmap = scaledBitmap.getBitmap();

        result = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(),
                Bitmap.Config.ARGB_8888);
        canvas = new Canvas(result);

        color = 0xff424242;
        paint = new Paint();
        rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
        rectF = new RectF(rect);
        roundPx = i;
        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);

        canvas.drawRoundRect(rectF, roundPx, roundPx, paint);

        paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);

        BitmapDrawable finalresult = new BitmapDrawable(result);
        saveImage_Rotate_white(finalresult.getBitmap());
        return finalresult;
    }

    private void saveImage_Rotate_white(Bitmap bitmap) {
        rec_image.setImageBitmap(bitmap);
        final Bitmap myRoundedImage = rec_image.getDrawingCache();

        if (bordered_file.exists())
            bordered_file.delete();
        try {
            FileOutputStream out = new FileOutputStream(bordered_file);
            myRoundedImage.compress(Bitmap.CompressFormat.PNG, 90, out);
            out.flush();
            out.close();

        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    private BitmapDrawable resizeBitmap(String rec_path2, int wantedWidth,
            int wantedHeight, ImageView view) {
        // TODO Auto-generated method stub
        BitmapFactory.Options options = new BitmapFactory.Options();
        options.inTempStorage = new byte[16 * 1024];

        Bitmap rec_bitmap = BitmapFactory.decodeFile(rec_path2, options);

        int width = rec_bitmap.getWidth();
        int height = rec_bitmap.getHeight();
        float xScale = ((float) wantedWidth) / width;
        float yScale = ((float) wantedHeight) / height;
        float scale = (xScale <= yScale) ? xScale : yScale;
        Matrix matrix = new Matrix();
        matrix.postScale(scale, scale);
        Bitmap scaledBitmap = Bitmap.createBitmap(rec_bitmap, 0, 0, width,
                height, matrix, true);
        BitmapDrawable finalImage = new BitmapDrawable(scaledBitmap);
        width = scaledBitmap.getWidth();
        height = scaledBitmap.getHeight();

        return finalImage;

    }

    static void saveImage_Rotate(Bitmap dest2) {

        if (rotated_File.exists())
            rotated_File.delete();
        try {
            FileOutputStream out = new FileOutputStream(rotated_File);
            dest2.compress(Bitmap.CompressFormat.PNG, 100, out);
            out.flush();
            out.close();

        } catch (Exception e) {
            e.printStackTrace();
        }

    }
}

Answer 1

好吧，您可以执行以下操作: 在您的 Activity、Fragment 中，或任何您正在膨胀 XML 的地方，为您的 View 启用缓存，如下所示:

ImageView myImageView= (ImageView)findViewById(R.id.imageView1);
myImageView.setDrawingCacheEnabled(true);

每当你想检索位图时，你只需像这样调用获取绘图缓存:

final Bitmap myRoundedImage = myImageView.getDrawingCache();

或者你可以这样做:

final Bitmap myRoundedImage = Bitmap.createBitmap( 
    myImageView.getWidth(), myImageView.getHeight(), Bitmap.Config.ARGB_8888 ); 
final Canvas canvas = new Canvas( myRoundedImage ); 
myImageView.draw( canvas );

一旦你有了你的位图，你所要做的就是将它保存到 SD 卡中，像这样:

try {
       FileOutputStream out = new FileOutputStream(filename);
       myRoundedImage.compress(Bitmap.CompressFormat.PNG, 90, out);
} catch (Exception e) {
       e.printStackTrace();
}