从URL下载图像,将其显示为具有默认行为的圆形图像

时间:2016-08-08 13:24:05

标签: android android-asynctask android-imageview

在坚持这个问题几天之后,我只想和你分享我的解决方案并节省你的时间。

问题
1.从任何URL下载图像
2.将其显示为圆形图像(如果下载成功)
3.或者在同一ImageView 中显示默认图像(如果下载失败)

[编辑] 我删除了我的答案,因为来自@Budius的非常有用的提示以及他在下面提供的更好的工作解决方案

2 个答案:

答案 0 :(得分:1)

从问题中完成任务的最佳方法是使用Picasso进行循环转换。

与以下代码类似:

Picasso
  .with(context)
  .load(url)
  .placeholder(placeHolderDrawable)
  .error(errorDrawable)
  .transform(circleTransform)
  .into(imageView);

以及从此链接复制的circleTransform代码:https://gist.github.com/julianshen/5829333

public class CircleTransform implements Transformation {
    @Override
    public Bitmap transform(Bitmap source) {
        int size = Math.min(source.getWidth(), source.getHeight());

        int x = (source.getWidth() - size) / 2;
        int y = (source.getHeight() - size) / 2;

        Bitmap squaredBitmap = Bitmap.createBitmap(source, x, y, size, size);
        if (squaredBitmap != source) {
            source.recycle();
        }

        Bitmap bitmap = Bitmap.createBitmap(size, size, source.getConfig());

        Canvas canvas = new Canvas(bitmap);
        Paint paint = new Paint();
        BitmapShader shader = new BitmapShader(squaredBitmap, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP);
        paint.setShader(shader);
        paint.setAntiAlias(true);

        float r = size/2f;
        canvas.drawCircle(r, r, r, paint);

        squaredBitmap.recycle();
        return bitmap;
    }

    @Override
    public String key() {
        return "circle";
    }
}

答案 1 :(得分:0)

compile 'com.squareup.picasso:picasso:2.5.0'//for load image from URL
compile 'de.hdodenhof:circleimageview:1.3.0'//for circle imageview

//add view in xml file
<de.hdodenhof.circleimageview.CircleImageView
                    android:id="@+id/ivProfileImage"
                    android:layout_width="100dp"
                    android:layout_height="100dp"
                    android:layout_centerHorizontal="true"
                    android:layout_margin="10dp"
                    android:contentDescription="@null"
                    app:border_color="#ffffff"
                    app:border_width="2dp" />
//Load image from Java file
private CircleImageView mIvProfileImage;
mIvProfileImage = (CircleImageView) findViewById(R.id.ivProfileImage);    
Picasso.with(getApplicationContext()).load("IMAGE URL")//download URL
.placeholder(R.drawable.ic_user_class)//use defaul image
.error(R.drawable.ic_user_class)//if failed                           
.into(mIvProfileImage);//imageview