39.Glide图片加载框架的使用

dependencies {
...
//图片加载
compile 'com.github.bumptech.glide:glide:3.7.0'
...
}

Glide.with(this)//上下文
.load(url)//下载地址
.placeholder(R.drawable.holder)//占位图
//.transform(new GlideCircleTransform(this))//转圆形
.into(mImageView);//控件对象

public class GlideCircleTransform extends BitmapTransformation {

public GlideCircleTransform(Context context) {
super(context);
}

@Override
protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
return circleCrop(pool, toTransform);
}

private static Bitmap circleCrop(BitmapPool pool, Bitmap source) {
if (source == null)
return null;

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

Bitmap squared = Bitmap.createBitmap(source, x, y, size, size);

Bitmap result = pool.get(size, size, Bitmap.Config.ARGB_8888);
if (result == null) {
result = Bitmap.createBitmap(size, size, Bitmap.Config.ARGB_8888);
}

Canvas canvas = new Canvas(result);
Paint paint = new Paint();
paint.setShader(new BitmapShader(squared, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
paint.setAntiAlias(true);
float r = size / 2f;
canvas.drawCircle(r, r, r, paint);
return result;
}

@Override
public String getId() {
return getClass().getName();
}
}

public class GlideRoundTransform extends BitmapTransformation {
private static float radius = 0f;

public GlideRoundTransform(Context context) {
this(context, 4);
}

public GlideRoundTransform(Context context, int dp) {
super(context);
this.radius = Resources.getSystem().getDisplayMetrics().density * dp;
}

@Override
protected Bitmap transform(BitmapPool pool, Bitmap toTransform, int outWidth, int outHeight) {
return roundCrop(pool, toTransform);
}

private static Bitmap roundCrop(BitmapPool pool, Bitmap source) {
if (source == null)
return null;

Bitmap result = pool.get(source.getWidth(), source.getHeight(), Bitmap.Config.ARGB_8888);
if (result == null) {
result = Bitmap.createBitmap(source.getWidth(), source.getHeight(), Bitmap.Config.ARGB_8888);
}

Canvas canvas = new Canvas(result);
Paint paint = new Paint();
paint.setShader(new BitmapShader(source, BitmapShader.TileMode.CLAMP, BitmapShader.TileMode.CLAMP));
paint.setAntiAlias(true);
RectF rectF = new RectF(0f, 0f, source.getWidth(), source.getHeight());
canvas.drawRoundRect(rectF, radius, radius, paint);
return result;
}

@Override
public String getId() {
return getClass().getName() + Math.round(radius);
}
}