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
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
你可以在你的布局中只使用ImageView,使用滑动,你可以使用这个方法应用圆角。
首先在你的gradle里写上,
compile 'com.github.bumptech.glide:glide:3.7.0'
对于有圆角的图像,
public void loadImageWithCorners(String url, ImageView view) {
Glide.with(context)
.load(url)
.asBitmap()
.centerCrop()
.placeholder(R.color.gray)
.error(R.color.gray)
.diskCacheStrategy(DiskCacheStrategy.SOURCE)
.into(new BitmapImageViewTarget(view) {
@Override
protected void setResource(Bitmap resource) {
RoundedBitmapDrawable circularBitmapDrawable =
RoundedBitmapDrawableFactory.create(context.getResources(), resource);
circularBitmapDrawable.setCornerRadius(32.0f); // radius for corners
view.setImageDrawable(circularBitmapDrawable);
}
});
}
调用方法:
loadImageWithCorners("your url","your imageview");
其他回答
我发现这两种方法在提出可行的解决方案时都非常有用。这是我的合成版本,它与像素无关,允许你有一些正方形的角,其余的角具有相同的半径(这是通常的用例)。 感谢以上两种解决方案:
public static Bitmap getRoundedCornerBitmap(Context context, Bitmap input, int pixels , int w , int h , boolean squareTL, boolean squareTR, boolean squareBL, boolean squareBR ) {
Bitmap output = Bitmap.createBitmap(w, h, Config.ARGB_8888);
Canvas canvas = new Canvas(output);
final float densityMultiplier = context.getResources().getDisplayMetrics().density;
final int color = 0xff424242;
final Paint paint = new Paint();
final Rect rect = new Rect(0, 0, w, h);
final RectF rectF = new RectF(rect);
//make sure that our rounded corner is scaled appropriately
final float roundPx = pixels*densityMultiplier;
paint.setAntiAlias(true);
canvas.drawARGB(0, 0, 0, 0);
paint.setColor(color);
canvas.drawRoundRect(rectF, roundPx, roundPx, paint);
//draw rectangles over the corners we want to be square
if (squareTL ){
canvas.drawRect(0, h/2, w/2, h, paint);
}
if (squareTR ){
canvas.drawRect(w/2, h/2, w, h, paint);
}
if (squareBL ){
canvas.drawRect(0, 0, w/2, h/2, paint);
}
if (squareBR ){
canvas.drawRect(w/2, 0, w, h/2, paint);
}
paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
canvas.drawBitmap(input, 0,0, paint);
return output;
}
我重写了ImageView,把这个放进去,这样我就可以用xml定义它了。 您可能想在这里添加一些super调用所做的逻辑,但我已经对其进行了注释,因为它对我的情况没有帮助。
@Override
protected void onDraw(Canvas canvas) {
//super.onDraw(canvas);
Drawable drawable = getDrawable();
Bitmap b = ((BitmapDrawable)drawable).getBitmap() ;
Bitmap bitmap = b.copy(Bitmap.Config.ARGB_8888, true);
int w = getWidth(), h = getHeight();
Bitmap roundBitmap = CropImageView.getRoundedCornerBitmap( getContext(), bitmap,10 , w, h , true, false,true, false);
canvas.drawBitmap(roundBitmap, 0,0 , null);
}
希望这能有所帮助!
虽然上面的答案是可行的,Romain Guy(核心Android开发人员)在他的博客中展示了一个更好的方法,通过使用着色器而不是创建位图的副本来使用更少的内存。该功能的一般要点如下:
BitmapShader shader;
shader = new BitmapShader(bitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(shader);
RectF rect = new RectF(0.0f, 0.0f, width, height);
// rect contains the bounds of the shape
// radius is the radius in pixels of the rounded corners
// paint contains the shader that will texture the shape
canvas.drawRoundRect(rect, radius, radius, paint);
与其他方法相比,这种方法的优点是:
不创建一个单独的位图副本,对于大图像使用大量内存[相对于这里的大多数其他答案] 支持反锯齿[vs clipPath方法] 支持alpha [vs xfermode+porterduff方法] 支持硬件加速[vs clipPath方法] 只在画布上绘制一次[相对于xfermode和clippath方法]
我创建了一个基于这段代码的RoundedImageView,它将这个逻辑包装到一个ImageView中,并添加了适当的ScaleType支持和可选的圆角边框。
使用这个得到圆形图像与边界
public static Bitmap getCircularBitmapWithBorder(Bitmap bitmap, int bordercolor) {
if (bitmap == null || bitmap.isRecycled()) {
return null;
}
int borderWidth=(int)(bitmap.getWidth()/40);
final int width = bitmap.getWidth() + borderWidth;
final int height = bitmap.getHeight() + borderWidth;
Bitmap canvasBitmap = Bitmap.createBitmap(width, height,
Bitmap.Config.ARGB_8888);
BitmapShader shader = new BitmapShader(bitmap, TileMode.CLAMP,
TileMode.CLAMP);
Paint paint = new Paint();
paint.setAntiAlias(true);
paint.setShader(shader);
Canvas canvas = new Canvas(canvasBitmap);
float radius = width > height ? ((float) height) / 2f
: ((float) width) / 2f;
canvas.drawCircle(width / 2, height / 2, radius, paint);
paint.setShader(null);
paint.setStyle(Paint.Style.STROKE);
paint.setColor(bordercolor);
paint.setStrokeWidth(borderWidth);
canvas.drawCircle(width / 2, height / 2, radius - borderWidth / 2,
paint);
return canvasBitmap;
}
有一个很酷的库可以让你塑造imageviews。
这里有一个例子:
<com.github.siyamed.shapeimageview.mask.PorterShapeImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
app:siShape="@drawable/shape_rounded_rectangle"
android:src="@drawable/neo"
app:siSquare="true"/>
形状定义:
<shape android:shape="rectangle" xmlns:android="http://schemas.android.com/apk/res/android">
<corners
android:topLeftRadius="18dp"
android:topRightRadius="18dp"
android:bottomLeftRadius="18dp"
android:bottomRightRadius="18dp" />
<solid android:color="@color/black" />
</shape>
结果:
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);
}
}