Android自定义ImageView实现图片圆形 ，椭圆和矩形圆角显示

Posted 2020-08-20 切切歆语

android中的ImageView只能显示矩形的图片，为了用户体验更多，Android实现圆角矩形，圆形或者椭圆等图形，一般通过自定义ImageView来实现，首先获取到图片的Bitmap，然后通过Paint和onDraw（）进行圆形图片显示。

效果图：

             

代码：

 

 1 activity_image.xml
 2 <?xml version="1.0" encoding="utf-8"?>
 3 <LinearLayoutxmlns:android="http://schemas.android.com/apk/res/android"
 4     android:layout_width="match_parent"
 5     android:layout_height="match_parent"
 6     android:orientation="vertical">
 7  
 8     <com.example.imageviewdrawdemo.ZQImageViewRoundOval
 9         android:id="@+id/cicle"
10         android:layout_width="100dp"
11         android:layout_height="100dp"
12         android:src="@drawable/qie">
13     </com.example.imageviewdrawdemo.ZQImageViewRoundOval>
14  
15     <com.example.imageviewdrawdemo.ZQImageViewRoundOval
16         android:id="@+id/roundRect"
17         android:layout_width="286dp"
18         android:layout_height="190dp"
19         android:layout_marginTop="10dp"
20         android:src="@drawable/l1">
21     </com.example.imageviewdrawdemo.ZQImageViewRoundOval>
22  
23     <com.example.imageviewdrawdemo.ZQImageViewRoundOval
24         android:id="@+id/oval"
25         android:layout_width="wrap_content"
26         android:layout_height="wrap_content"
27         android:layout_marginTop="20dp"
28         android:src="@drawable/l2">
29     </com.example.imageviewdrawdemo.ZQImageViewRoundOval>
30  
31 </LinearLayout>

 

  1 /**
  2  * 实现圆形、圆角，椭圆等自定义图片View。
  3  * @author zq
  4  *
  5  */
  6 public class  ZQImageViewRoundOval extends ImageView {
  7  
  8     private Paint mPaint;
  9  
 10     private int mWidth;
 11  
 12     private int mHeight;
 13  
 14     private int mRadius;//圆半径
 15  
 16     private RectF mRect;//矩形凹行大小
 17  
 18     private int mRoundRadius;//圆角大小
 19  
 20     private BitmapShader mBitmapShader;//图形渲染
 21  
 22     private Matrix mMatrix;
 23  
 24     private int mType;//记录是圆形还是圆角矩形
 25  
 26     public static final int TYPE_CIRCLE = 0;//圆形
 27     public static final int TYPE_ROUND = 1;//圆角矩形
 28     public static final int TYPE_OVAL = 2;//椭圆形
 29     public static final int DEFAUT_ROUND_RADIUS = 10;//默认圆角大小
 30  
 31     public ZQImageViewRoundOval(Context context) {
 32         this(context, null);
 33         // TODOAuto-generated constructor stub
 34     }
 35  
 36     public ZQImageViewRoundOval(Context context, AttributeSet attrs) {
 37         this(context,attrs, 0);
 38         // TODOAuto-generated constructor stub
 39     }
 40  
 41     public ZQImageViewRoundOval(Context context, AttributeSet attrs,int defStyle){
 42         super(context,attrs, defStyle);
 43         initView();
 44     }
 45  
 46     private void initView() {
 47         mPaint = new Paint();
 48         mPaint.setAntiAlias(true);
 49         mMatrix = new Matrix();
 50         mRoundRadius = DEFAUT_ROUND_RADIUS;
 51     }
 52  
 53     @Override
 54     protected void onMeasure(int widthMeasureSpec,intheightMeasureSpec) {
 55         // TODOAuto-generated method stub
 56         super.onMeasure(widthMeasureSpec,heightMeasureSpec);
 57         // 如果是绘制圆形，则强制宽高大小一致
 58         if (mType ==TYPE_CIRCLE) {
 59             mWidth = Math.min(getMeasuredWidth(),getMeasuredHeight());
 60             mRadius = mWidth / 2;
 61             setMeasuredDimension(mWidth, mWidth);
 62         }
 63  
 64     }
 65  
 66     @Override
 67     protected void onDraw(Canvas canvas) {
 68  
 69         if (null ==getDrawable()) {
 70             return;
 71         }
 72         setBitmapShader();
 73         if (mType ==TYPE_CIRCLE) {
 74             canvas.drawCircle(mRadius, mRadius, mRadius, mPaint);
 75         } else if (mType == TYPE_ROUND) {
 76             mPaint.setColor(Color.RED);
 77             canvas.drawRoundRect(mRect, mRoundRadius, mRoundRadius, mPaint);
 78         }else if(mType == TYPE_OVAL){
 79             canvas.drawOval(mRect, mPaint);
 80         }
 81     }
 82  
 83     @Override
 84     protected void onSizeChanged(int w,int h, int oldw,int oldh) {
 85         // TODOAuto-generated method stub
 86         super.onSizeChanged(w,h, oldw, oldh);
 87         mRect = new RectF(0,0, getWidth(), getHeight());
 88     }
 89  
 90     /**
 91      * 设置BitmapShader
 92      */
 93     private void setBitmapShader() {
 94         Drawable drawable = getDrawable();
 95         if (null ==drawable) {
 96             return;
 97         }
 98         Bitmap bitmap = drawableToBitmap(drawable);
 99         // 将bitmap作为着色器来创建一个BitmapShader
100         mBitmapShader = newBitmapShader(bitmap, TileMode.CLAMP, TileMode.CLAMP);
101         float scale =1.0f;
102         if (mType ==TYPE_CIRCLE) {
103             // 拿到bitmap宽或高的小值
104             int bSize =Math.min(bitmap.getWidth(), bitmap.getHeight());
105             scale = mWidth * 1.0f /bSize;
106  
107         } else if (mType == TYPE_ROUND ||mType == TYPE_OVAL) {
108             // 如果图片的宽或者高与view的宽高不匹配，计算出需要缩放的比例；缩放后的图片的宽高，一定要大于我们view的宽高；所以我们这里取大值；
109             scale = Math.max(getWidth() * 1.0f/ bitmap.getWidth(), getHeight() * 1.0f / bitmap.getHeight());
110         }
111         // shader的变换矩阵，我们这里主要用于放大或者缩小
112         mMatrix.setScale(scale,scale);
113         // 设置变换矩阵
114         mBitmapShader.setLocalMatrix(mMatrix);
115         mPaint.setShader(mBitmapShader);
116  
117     }
118  
119     /**
120      * drawable转bitmap
121      *
122      * @paramdrawable
123      * @return
124      */
125     private Bitmap drawableToBitmap(Drawable drawable) {
126         if (drawableinstanceof BitmapDrawable) {
127             BitmapDrawable bitmapDrawable =(BitmapDrawable) drawable;
128             returnbitmapDrawable.getBitmap();
129         }
130         int w =drawable.getIntrinsicWidth();
131         int h =drawable.getIntrinsicHeight();
132         Bitmap bitmap = Bitmap.createBitmap(w,h, Config.ARGB_8888);
133         Canvas canvas = newCanvas(bitmap);
134         drawable.setBounds(0, 0, w, h);
135         drawable.draw(canvas);
136         return bitmap;
137     }
138     /**
139      * 单位dp转单位px
140      */
141     public int dpTodx(int dp){
142        
143         return (int)TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, 
144                 dp,getResources().getDisplayMetrics()); 
145     }
146    
147     public int getType(){
148         return mType;
149     }
150     /**
151      * 设置图片类型：圆形、圆角矩形、椭圆形
152      * @param mType
153      */
154     public void setType(int mType) {
155         if(this.mType !=mType){
156             this.mType = mType;
157             invalidate();
158         }
159        
160     }
161     public int getRoundRadius() {
162         return mRoundRadius;
163     }
164     /**
165      * 设置圆角大小
166      * @parammRoundRadius
167      */
168     public void setRoundRadius(int mRoundRadius) {
169         if(this.mRoundRadius !=mRoundRadius){
170             this.mRoundRadius =mRoundRadius;
171             invalidate();
172         }
173        
174     }
175 }

 

 1 MainActivity类
 2 /****
 3  *
 4  * 自定义ImageView实现圆形图片，圆角矩形图片 椭圆图片
 5  *
 6  * @authorzq
 7  *
 8  */
 9 public class MainActivity extends Activity {
10  
11   
12     private  ZQImageViewRoundOvaliv_circle;//圆形图片
13     private ZQImageViewRoundOvaliv_roundRect;//圆角矩形图片
14     private ZQImageViewRoundOvaliv_oval;//椭圆图片
15     @Override
16     protected void onCreate(Bundle savedInstanceState) {
17         super.onCreate(savedInstanceState);
18       setContentView(R.layout.activity_image);
19       initViews();
20    }
21    /**
22     * 初始化Views
23     */
24    private void initViews(){
25       iv_circle =(ZQImageViewRoundOval)findViewById(R.id.cicle);
26       iv_roundRect =(ZQImageViewRoundOval)findViewById(R.id.roundRect);
27       iv_oval =(ZQImageViewRoundOval)findViewById(R.id.oval);
28       
29      
30       iv_roundRect.setType(ZQImageViewRoundOval.TYPE_ROUND);
31       iv_roundRect.setRoundRadius(6);//矩形凹行大小
32       
33        iv_oval.setType(ZQImageViewRoundOval.TYPE_OVAL);
34        iv_oval.setRoundRadius(45);//圆角大小
35    }
36 }

 

源码下载：

 

Eclipse下载：http://download.csdn.net/detail/dickyqie/9621330

AndroidStudio下载： https://github.com/DickyQie/ImageViewDrawDemo