1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.example.android.apis.view;
18 
19 import android.content.Context;
20 import android.graphics.Bitmap;
21 import android.graphics.Canvas;
22 import android.graphics.Paint;
23 import android.util.AttributeSet;
24 import android.util.Log;
25 import android.view.MotionEvent;
26 import android.view.PointerIcon;
27 import android.widget.Button;
28 
29 public class LivePointerIconButton extends Button {
LivePointerIconButton(Context context)30     public LivePointerIconButton(Context context) {
31         this(context, null);
32     }
33 
LivePointerIconButton(Context context, AttributeSet attrs)34     public LivePointerIconButton(Context context, AttributeSet attrs) {
35         super(context, attrs);
36     }
37 
LivePointerIconButton(Context context, AttributeSet attrs, int defStyleAttr)38     public LivePointerIconButton(Context context, AttributeSet attrs, int defStyleAttr) {
39         super(context, attrs, defStyleAttr);
40     }
41 
LivePointerIconButton(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes)42     public LivePointerIconButton(Context context, AttributeSet attrs,
43                                   int defStyleAttr, int defStyleRes) {
44         super(context, attrs, defStyleAttr, defStyleRes);
45     }
46 
47     @Override
onResolvePointerIcon(MotionEvent event, int pointerIndex)48     public PointerIcon onResolvePointerIcon(MotionEvent event, int pointerIndex) {
49         int cursorSize = getHeight();
50 
51         Bitmap bitmap = Bitmap.createBitmap(cursorSize, cursorSize, Bitmap.Config.ARGB_8888);
52         Canvas canvas = new Canvas(bitmap);
53 
54         Paint paint = new Paint();
55         paint.setARGB(255, 255, 255, 255);
56         paint.setStyle(Paint.Style.STROKE);
57         final int strokeWidth = 4;
58         paint.setStrokeWidth(strokeWidth);
59 
60         // Draw a large circle filling the bitmap.
61         final int outerCenterX = cursorSize / 2;
62         final int outerCenterY = cursorSize / 2;
63         final int outerRadius = cursorSize / 2 - strokeWidth;
64         canvas.drawCircle(outerCenterX, outerCenterY, outerRadius, paint);
65 
66         // Compute relative offset of the mouse pointer from the view center.
67         // It should be between -0.5 and 0.5.
68         final float relativeX = (event.getX(pointerIndex) / getWidth()) - 0.5f;
69         final float relativeY = (event.getY(pointerIndex) / getHeight()) - 0.5f;
70 
71         // Draw a smaller circle inside the large circle, offset towards the center of the view.
72         final int innerCenterX = (int) (cursorSize * (1 - relativeX) / 2);
73         final int innerCenterY = (int) (cursorSize * (1 - relativeY) / 2);
74         final int innerRadius = cursorSize / 6;
75         if (event.getAction() == MotionEvent.ACTION_MOVE) {
76             // Fill the inner circle if the mouse button is down.
77             paint.setStyle(Paint.Style.FILL);
78         }
79         canvas.drawCircle(innerCenterX, innerCenterY, innerRadius, paint);
80 
81         final int hotSpotX = bitmap.getWidth() / 2;
82         final int hotSpotY = bitmap.getHeight() / 2;
83         return PointerIcon.create(bitmap, hotSpotX, hotSpotY);
84     }
85 }
86