每次点击图片一次，图片旋转90°

第一步：自定义ImageView

 1 /**
 2  * @author Sigal
 3  * on 2018/12/17
 4  * note: 每次点击旋转90度的ImageView
 5  */
 6 @SuppressLint("AppCompatCustomView")
 7 public class RotateImageView extends ImageView {
 8     int mdegree =0;
 9 
10     public RotateImageView(Context context, AttributeSet attrs) {
11         super(context, attrs);
12     }
13 
14     public RotateImageView(Context context) {
15         super(context);
16     }
17 
18     @Override
19     protected void onDraw(Canvas canvas) {
20         int top = getTop();
21         int left = getLeft();
22         int right = getRight();
23         int bottom = getBottom();
24         float centralX = (right - left) / 2.0f;
25         float centralY = (bottom - top) / 2.0f;
26         //保存旋转前画布状态
27         canvas.save();
28         canvas.rotate(mdegree, centralX, centralY);
29         super.onDraw(canvas);
30         //取去出旋转前保存的状态
31         canvas.restore();
32     }
33     public void setDegree(int degree) {
34         mdegree = degree;
35         invalidate();
36     }
37 }

第二步：调用RotateImageView 

1 　　　　　RotateImageView imageView = findViewById(R.id.img);
2         imageView.setOnClickListener(new View.OnClickListener() {
3             @Override
4             public void onClick(View v) {
5                 count++;
6                 imageView.setDegree(90*count);
7             }
8         });

第三步：布局文件

<com.sun.test01.RotateImageView
        android:id="@+id/img"
        android:layout_width="200dp"
        android:layout_height="300dp"
        android:scaleType="centerInside"
        android:src="@drawable/img_02" />

 

posted on 2018-12-17 21:34  HarperSun  阅读(343)  评论(0)  编辑  收藏  举报

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