在Android中,ImageView默认是一个矩形。如何使它成为一个圆角矩形(剪辑我的位图的所有4个角为圆角矩形)在ImageView?


请注意,从2021年起,只需使用ShapeableImageView


当前回答

这里要回答的问题是: 如何在Android中创建一个圆形ImageView ?

public static Bitmap getRoundBitmap(Bitmap bitmap) {

    int min = Math.min(bitmap.getWidth(), bitmap.getHeight());

    Bitmap bitmapRounded = Bitmap.createBitmap(min, min, bitmap.getConfig());

    Canvas canvas = new Canvas(bitmapRounded);
    Paint paint = new Paint();
    paint.setAntiAlias(true);
    paint.setShader(new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP));
    canvas.drawRoundRect((new RectF(0.0f, 0.0f, min, min)), min/2, min/2, paint);

    return bitmapRounded;
}

其他回答

    /**
 * Background Async task to load user profile picture from url
 */
private class LoadProfileImage extends AsyncTask<String, Void, RoundedBitmapDrawable> {
    ImageView profileImageView;

    public LoadProfileImage(ImageView profileImageView) {
        this.profileImageView = profileImageView;
    }

    protected RoundedBitmapDrawable doInBackground(String... urls) {
        String photoUrl = urls[0];
        RoundedBitmapDrawable profileRoundedDrawable = null;
        try {
            InputStream inputStream = new java.net.URL(photoUrl).openStream();
            Resources res = getResources();

            profileRoundedDrawable = RoundedBitmapDrawableFactory.create(res, inputStream);
            profileRoundedDrawable.setCircular(true);
        } catch (Exception e) {
            Log.e("Error", e.getMessage());
            e.printStackTrace();
        }
        return profileRoundedDrawable;
    }

    protected void onPostExecute(RoundedBitmapDrawable result) {
        profileImageView.setImageDrawable(result);
    }
}

如果你的图片在互联网上,最好的方法是使用glide和RoundedBitmapDrawableFactory(来自API 21 -但在支持库中可用),如下所示:

 Glide.with(ctx).load(url).asBitmap().centerCrop().into(new BitmapImageViewTarget(imageView) {
    @Override
    protected void setResource(Bitmap res) {
        RoundedBitmapDrawable bitmapDrawable =
             RoundedBitmapDrawableFactory.create(ctx.getResources(), res);
        bitmapDrawable.setCircular(true);//comment this line and uncomment the next line if you dont want it fully cricular
        //circularBitmapDrawable.setCornerRadius(cornerRadius);
        imageView.setImageDrawable(bitmapDrawable);
    }
});

这里使用ImageLoader

创建DisplayImageOptions:

DisplayImageOptions options = new DisplayImageOptions.Builder()
    // this will make circle, pass the width of image 
    .displayer(new RoundedBitmapDisplayer(getResources().getDimensionPixelSize(R.dimen.image_dimen_menu))) 
    .cacheOnDisc(true)
    .build();

imageLoader.displayImage(url_for_image,ImageView,options);

或者你也可以从Square上使用毕加索图书馆。

Picasso.with(mContext)
    .load(com.app.utility.Constants.BASE_URL+b.image)
    .placeholder(R.drawable.profile)
    .error(R.drawable.profile)
    .transform(new RoundedTransformation(50, 4))
    .resizeDimen(R.dimen.list_detail_image_size, R.dimen.list_detail_image_size)
    .centerCrop()
    .into(v.im_user);

你可以在这里下载RoundedTransformation文件 在这里

我知道这个问题已经过时了,但这里有另一种更简单的四舍五入图像的方法:

这是一种编程方法。

创造你的空白……

} public static Bitmap getRoundedCornerBitmap(Bitmap bitmap, int pixels) { Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Bitmap.Config.ARGB_8888);
Canvas canvas = new Canvas(output); final int color = 0xff424242;
final Paint paint = new Paint(); final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight());
final RectF rectF = new RectF(rect);
final float roundPx = pixels; paint.setAntiAlias(true); 
canvas.drawARGB(0, 0, 0, 0); paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(bitmap, rect, rect, paint); return output;

加载图像,然后设置圆角

imageview1.setImageResource(R.drawable.yourimage);

Bitmap bm = ((android.graphics.drawable.BitmapDrawable) imageview1.getDrawable()).getBitmap();
imageview1.setImageBitmap(getRoundedCornerBitmap(bm, 30)); 

以30为半径,你会得到这样的结果:

不管我的图像看起来如何,它只是一个放大的小图标

如果你们中有人面临这个问题

大多数情况下,你使用的是Android Studio。由于图像大小的调整和所有在Android工作室,你可能会遇到这个问题。解决这个问题的一个简单方法是减小drawCircle()中的圆的半径。在我的情况下,我使用这个修复

使用画布。drawCircle(100,100,90, paint);而不是帆布。drawCircle(100,100,100, paint);这绝对能解决你的问题。

下面是最终编辑的代码:-

  public class Profile extends ActionBarActivity {


    TextView username;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.profile);


        username= (TextView) findViewById(R.id.txt);

        String recievedusername=getIntent().getExtras().getString("toname");
        username.setText(recievedusername);


        Bitmap bm = BitmapFactory.decodeResource(getResources(),
                R.mipmap.gomez);

        Bitmap resizedBitmap = Bitmap.createScaledBitmap(bm, 200,200, false);
        Bitmap conv_bm=getCircleBitmap(resizedBitmap,100);
        // set circle bitmap
        ImageView mImage = (ImageView) findViewById(R.id.profile_image);
        mImage.setImageBitmap(conv_bm);
        // TODO Auto-generated method stub
    }
    private Bitmap getCircleBitmap(Bitmap bitmap , int pixels) {
        final Bitmap output = Bitmap.createBitmap(bitmap.getWidth(),
                bitmap.getHeight(), Bitmap.Config.ARGB_8888);
        final Canvas canvas = new Canvas(output);
        final int color = 0xff424242;
        final Paint paint = new Paint();
        final Rect rect = new Rect(0, 0, bitmap.getWidth(),bitmap.getHeight());
        final RectF rectF = new RectF(rect);
        paint.setAntiAlias(true);
        canvas.drawARGB(0, 0, 0, 0);
        paint.setColor(color);
        canvas.drawCircle(100,100, 90, paint);
        paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
        canvas.drawBitmap(bitmap, rect, rect, paint);
        bitmap.recycle();
        return output;
    }
    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        MenuInflater inflater = getMenuInflater();
        inflater.inflate(R.menu.menu_apploud, menu);
        return super.onCreateOptionsMenu(menu);
    }
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        //noinspection SimplifiableIfStatement
        if (id == R.id.action_addnew) {
            Intent i;
            i=new Intent(Profile.this,ApplaudSomeone.class);
            startActivity(i);
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}