Android开发：AS开发圆形图片外框设计
图片以圆形外框的形式显示的方式目前也已经非常普遍了，做为一个应用开发者来说，用户界面的圆形图片外框要求是必不可少的，接下来我就来介绍下我所掌握的几种基本的方法：
1、使用第三方资源Fresco
第三方资源用起来是最方便的，很适合新手，跟着做就行了：
第一步：添加依赖文件(com.facebook.fresco:fresco:0.14.1) 网上添加的手段很多，我就不一一介绍了，你可以直接在build.gradle文件下添加以下代码即可： dependencies { compile ‘com.facebook.fresco:fresco:0.14.1’ } 注意：版本可能有更新，操作是差不多的。第二步：实例化，执行以下指令： Fresco.initialize(this);（在onCreate()方法下执行）第三步：授权 <uses-permission android:name=“android.permission.INTERNET”/>第四步：申请空间： <com.facebook.drawee.view.SimpleDraweeView android:id="@+id/drawee_img" fresco:roundAsCircle=“true” fresco:roundedCornerRadius=“20dp” android:layout_width=“80dp” android:layout_height=“80dp” />第五步：调用： SimpleDraweeView draweeView = (SimpleDraweeView) findViewById(R.id.drawee_img); Uri uri = Uri.parse(“https://img-blog.csdnimg.cn/20190613104157382.jpg”); draweeView.setImageURI(uri);注意： 该方法操作简单但是豪流量，哈哈！不离线
2、自定义ImageView控件
自定义类，新建CircleImageView.java文件
public class CircleImageView extends ImageView {
private Paint mPaint
;
private int mRadius
;
private float mScale
;
public CircleImageView(Context context
) {
super(context
);
}
public CircleImageView(Context context
, AttributeSet attrs
) {
super(context
, attrs
);
}
public CircleImageView(Context context
, AttributeSet attrs
, int defStyleAttr
) {
super(context
, attrs
, defStyleAttr
);
}
@Override
protected void onMeasure(int widthMeasureSpec
, int heightMeasureSpec
) {
super.onMeasure(widthMeasureSpec
, heightMeasureSpec
);
int size
= Math
.min(getMeasuredWidth(), getMeasuredHeight());
mRadius
= size
/ 2;
setMeasuredDimension(size
, size
);
}
@Override
protected void onDraw(Canvas canvas
) {
mPaint
= new Paint();
mPaint
.setAntiAlias(true);
Bitmap bitmap
= drawableToBitmap(getDrawable());
BitmapShader bitmapShader
= new BitmapShader(bitmap
, Shader
.TileMode
.CLAMP
, Shader
.TileMode
.CLAMP
);
mScale
= (mRadius
* 2.0f) / Math
.min(bitmap
.getHeight(), bitmap
.getWidth());
Matrix matrix
= new Matrix();
matrix
.setScale(mScale
, mScale
);
bitmapShader
.setLocalMatrix(matrix
);
mPaint
.setShader(bitmapShader
);
canvas
.drawCircle(mRadius
, mRadius
, mRadius
, mPaint
);
}
private Bitmap
drawableToBitmap(Drawable drawable
) {
if (drawable
instanceof BitmapDrawable) {
BitmapDrawable bd
= (BitmapDrawable
) drawable
;
return bd
.getBitmap();
}
int w
= drawable
.getIntrinsicWidth();
int h
= drawable
.getIntrinsicHeight();
Bitmap bitmap
= Bitmap
.createBitmap(w
, h
, Bitmap
.Config
.ARGB_8888
);
Canvas canvas
= new Canvas(bitmap
);
drawable
.setBounds(0, 0, w
, h
);
drawable
.draw(canvas
);
return bitmap
;
}
}
调用：
<com
.sylanty
.test
.CircleImageView
android
:id
="@+id/image"
android
:layout_width
="200dp"
android
:layout_height
="200dp"
android
:layout_centerInParent
="true"
android
:scaleType
="centerCrop"
android
:src
="@drawable/xt"
/>
3、裁剪成圆框
思路1：
public static Bitmap
createCircleImage(Bitmap source
) {
int length
= source
.getWidth() < source
.getHeight() ? source
.getWidth() : source
.getHeight();
Paint paint
= new Paint();
paint
.setAntiAlias(true);
Bitmap target
= Bitmap
.createBitmap(length
, length
, Bitmap
.Config
.ARGB_8888
);
Canvas canvas
= new Canvas(target
);
canvas
.drawCircle(length
/ 2, length
/ 2, length
/ 2, paint
);
paint
.setXfermode(new PorterDuffXfermode(PorterDuff
.Mode
.SRC_IN
));
canvas
.drawBitmap(source
, 0, 0, paint
);
return target
;
}
思路2：
public static Bitmap
createCircleImage(Bitmap source
) {
int width
= source
.getWidth();
int height
= source
.getHeight();
float raduis
= Math
.min(width
, height
) * 0.5f;
Paint paint
= new Paint(Paint
.ANTI_ALIAS_FLAG
);
paint
.setShader(new BitmapShader(source
, Shader
.TileMode
.CLAMP
, Shader
.TileMode
.CLAMP
));
Bitmap bitmap
= Bitmap
.createBitmap(width
, height
, source
.getConfig());
Canvas canvas
= new Canvas(bitmap
);
canvas
.drawCircle(width
* 0.5f, height
*0.5f, raduis
, paint
);
return bitmap；
}
与Picasso结合使用：
Picasso
.with(mContext
).load(Constant
.format(headUrl
)).transform(new Transformation() {
@Override
public Bitmap
transform(Bitmap source
) {
source
=createCircleImage（source）；
source
.recycle();
return bitmap
;
}
@Override
public String
key() {
Log
.d(TAG
, "key() called");
return "key";
}
}).into(meHeader
);
总结：
以前没有做笔记，现在把笔记补全，学习快乐！！！
为了那个轻易许下的梦
