Android自定义进度条

Android原生控件只有横向进度条一种，而且没法变换样式，比如原生rom的样子





很丑是吧，当伟大的产品设计要求更换前背景，甚至纵向，甚至圆弧状的，咋办，比如





ok，我们开始吧：

一）变换前背景

先来看看progressbar的属性：

1. <ProgressBar

2. android:id="@+id/progressBar"

3. style="?android:attr/progressBarStyleHorizontal"

4. android:layout_width="match_parent"

5. android:layout_height="wrap_content"

6. android:layout_margin="5dip"

7. android:layout_toRightOf="@+id/progressBarV"

8. android:indeterminate="false"

9. android:padding="2dip"

10. android:progress="50" />

根据style="?android:attr/progressBarStyleHorizontal"，我们找到源码中的style.xml

1. <style name="Widget.ProgressBar.Horizontal">

2. <item name="android:indeterminateOnly">false</item>

3. <item name="android:progressDrawable">@android:drawable/progress_horizontal</item>

4. <item name="android:indeterminateDrawable">@android:drawable/progress_indeterminate_horizontal</item>

5. <item name="android:minHeight">20dip</item>

6. <item name="android:maxHeight">20dip</item>

7. </style>

看到

<item name="android:progressDrawable">@android:drawable/progress_horizontal</item>

木有，继续发掘源码，找到drawable下面的progress_horizontal.xml，这就是我们今天的主角了：

1. <layer-list xmlns:android="http://schemas.android.com/apk/res/android">

2.

3. <item android:id="@android:id/background">

4. <shape>

5. <corners android:radius="5dip" />

6. <gradient

7. android:startColor="#ff9d9e9d"

8. android:centerColor="#ff5a5d5a"

9. android:centerY="0.75"

10. android:endColor="#ff747674"

11. android:angle="270"

12. />

13. </shape>

14. </item>

15.

16. <item android:id="@android:id/secondaryProgress">

17. <clip>

18. <shape>

19. <corners android:radius="5dip" />

20. <gradient

21. android:startColor="#80ffd300"

22. android:centerColor="#80ffb600"

23. android:centerY="0.75"

24. android:endColor="#a0ffcb00"

25. android:angle="270"

26. />

27. </shape>

28. </clip>

29. </item>

30.

31. <item android:id="@android:id/progress">

32. <clip>

33. <shape>

34. <corners android:radius="5dip" />

35. <gradient

36. android:startColor="#ffffd300"

37. android:centerColor="#ffffb600"

38. android:centerY="0.75"

39. android:endColor="#ffffcb00"

40. android:angle="270"

41. />

42. </shape>

43. </clip>

44. </item>

45.

46. </layer-list>

看到android:id="@android:id/progress"木有，看到android:id="@android:id/secondaryProgress"木有

把这个文件复制到自己工程下的drawable，就可以随心所欲的修改shape的属性，渐变，圆角等等

那么怎么放一个图片进去呢，ok，新建progress_horizontal1.xml：

1. <?xml version="1.0" encoding="utf-8"?>

2. <layer-list xmlns:android="http://schemas.android.com/apk/res/android">

3.

4. <item android:id="@android:id/progress" android:drawable="@drawable/progressbar" />

5.

6. </layer-list>

在android:drawable中指定你处理好的图片

然后回到布局中

1. <ProgressBar

2. android:id="@+id/progressBar1"

3. android:layout_width="match_parent"

4. android:layout_height="wrap_content"

5. android:layout_below="@+id/progressBar"

6. android:layout_margin="5dip"

7. android:layout_toRightOf="@+id/progressBarV"

8. android:background="@drawable/progress_bg"

9. android:indeterminate="false"

10. android:indeterminateOnly="false"

11. android:maxHeight="20dip"

12. android:minHeight="20dip"

13. android:padding="2dip"

14. android:progress="50"

15. android:progressDrawable="@drawable/progress_horizontal1" />

android:background="@drawable/progress_bg"指定背景

android:progressDrawable="@drawable/progress_horizontal1"前景使用上面的progress_horizontal1

ok，搞定





注意看，四角还是有圆倒角的，貌似是系统自己加上去的，总之我的图片里面是没有做这个倒角处理的

二）纵向进度条

还是得从源码入手，看回progress_horizontal.xml

1. <item android:id="@android:id/progress">

2. <clip>

3. <shape>

4. <corners android:radius="5dip" />

5. <gradient

6. android:startColor="#ffffd300"

7. android:centerColor="#ffffb600"

8. android:centerY="0.75"

9. android:endColor="#ffffcb00"

10. android:angle="270"

11. />

12. </shape>

13. </clip>

14. </item>

为什么shape外面要包一层clip呢，官方文档解释是clipdrawable是可以自我复制的，来看看定义

1. <?xml version="1.0" encoding="utf-8"?>

2. <clip

3. xmlns:android="http://schemas.android.com/apk/res/android"

4. android:drawable="@drawable/drawable_resource"

5. android:clipOrientation=["horizontal" | "vertical"]

6. android:gravity=["top" | "bottom" | "left" | "right" | "center_vertical" |

7. "fill_vertical" | "center_horizontal" | "fill_horizontal" |

8. "center" | "fill" | "clip_vertical" | "clip_horizontal"] />

android:clipOrientation有两个属性，默认为horizontal

android:gravity有两个属性，默认为left

那我们试试改成vertical和bottom会有什么效果，新建一个progress_vertical.xml，把源码progress_horizontal.xml的内容复制过来，这里去掉了secondaryProgress，修改了clip，shape的渐变中心centerY改为centerX

1. <item android:id="@android:id/progress">

2. <clip

3. android:clipOrientation="vertical"

4. android:gravity = "bottom">

5. <shape>

6. <corners android:radius="5dip" />

7. <gradient

8. android:startColor="#ffffd300"

9. android:centerColor="#ffffb600"

10. android:centerX="0.75"

11. android:endColor="#ffffcb00"

12. android:angle="90"

13. />

14. </shape>

15. </clip>

16. </item>

布局中android:progressDrawable="@drawable/progress_vertical"

ok，搞定，就是这么简单：





三）弧形bar

这个也许算不上是进度条，用的也不多，最多也就仪表盘用用，不然谁会把进度条整成圆弧的呢。好吧这个可不是改改源码就能搞定的，看代码

1. public class Arcs extends View {

2. private Paint mArcPaint;

3. private Paint mArcBGPaint;

4.

5. private RectF mOval;

6. private float mSweep = 0;

7. private int mSpeedMax = 200;

8. private int mThreshold = 100;

9. private int mIncSpeedValue = 0;

10. private int mCurrentSpeedValue = 0;

11. private float mCenterX;

12. private float mCenterY;

13. private float mSpeedArcWidth;

14.

15. private final float SPEED_VALUE_INC = 2;

16.

17. ..........

18.

19. }

首先是一堆成员变量，两个Paint用来画圆弧一个前景一个背景，一个RectF圆弧就画在上面，然后是一些控制参数比如sweep圆弧扫过的角度，xy坐标等等

1. mArcPaint = new Paint(Paint.ANTI_ALIAS_FLAG);

2. mArcPaint.setStyle(Paint.Style.STROKE);

3. mArcPaint.setStrokeWidth(mSpeedArcWidth);

4. // mPaint.setStrokeCap(Paint.Cap.ROUND);

5. mArcPaint.setColor(0xff81ccd6);

6. BlurMaskFilter mBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.INNER);

7. mArcPaint.setMaskFilter(mBlur);

8.

9. mArcBGPaint = new Paint(Paint.ANTI_ALIAS_FLAG);

10. mArcBGPaint.setStyle(Paint.Style.STROKE);

11. mArcBGPaint.setStrokeWidth(mSpeedArcWidth+8);

12. mArcBGPaint.setColor(0xff171717);

13.

14. BlurMaskFilter mBGBlur = new BlurMaskFilter(8, BlurMaskFilter.Blur.INNER);

15. mArcBGPaint.setMaskFilter(mBGBlur);

设置两个画笔，颜色，宽度，样式等等，BlurMaskFilter笔是边缘模糊效果，有几种，可以自己尝试

1. @Override

2. protected void onSizeChanged(int w, int h, int ow, int oh) {

3. super.onSizeChanged(w, h, ow, oh);

4. Log.i("onSizeChanged w", w+"");

5. Log.i("onSizeChanged h", h+"");

6. mCenterX = w * 0.5f; // remember the center of the screen

7. mCenterY = h - mSpeedArcWidth;

8. mOval = new RectF(mCenterX - mCenterY, mSpeedArcWidth, mCenterX + mCenterY, mCenterY * 2);

9. }

重写父类View的onSizeChanged，为的是自己根据布局中的大小做居中处理

1. @Override

2. protected void onDraw(Canvas canvas) {

3. drawSpeed(canvas);

4. calcSpeed();

5. }

6.

7. private void drawSpeed(Canvas canvas) {

8. canvas.drawArc(mOval, 179, 181, false, mArcBGPaint);

9.

10. mSweep = (float) mIncSpeedValue / mSpeedMax * 180;

11. if (mIncSpeedValue > mThreshold) {

12. mArcPaint.setColor(0xFFFF0000);

13. }

14. else {

15. mArcPaint.setColor(0xFF00B0F0);

16. }

17.

18. canvas.drawArc(mOval, 180, mSweep, false, mArcPaint);

19. }

20.

21. private void calcSpeed() {

22. if (mIncSpeedValue < mCurrentSpeedValue) {

23. mIncSpeedValue += SPEED_VALUE_INC;

24. if (mIncSpeedValue > mCurrentSpeedValue) {

25. mIncSpeedValue = mCurrentSpeedValue;

26. }

27. invalidate();

28. }

29. else if (mIncSpeedValue > mCurrentSpeedValue) {

30. mIncSpeedValue -= SPEED_VALUE_INC;

31. if (mIncSpeedValue < mCurrentSpeedValue) {

32. mIncSpeedValue = mCurrentSpeedValue;

33. }

34. invalidate();

35. }

36. }

重写onDraw以便重绘canvas

drawSpeed里面

通过计算mSweep = (float) mIncSpeedValue / mSpeedMax * 180;

然后canvas.drawArc(mOval, 180, mSweep, false, mArcPaint);

会根据mSweep的变化，画出相应长度的弧度来

根据与阈值的对比，还可以设定不同的 颜色：

if (mIncSpeedValue > mThreshold) {

mArcPaint.setColor(0xFFFF0000);

}

else {

mArcPaint.setColor(0xFF00B0F0);

}

calcSpeed通过一个步进来控制增量或减量，以使弧度自然过渡，减少跳跃

ok，大功告成





摘自 winwyf 的BLOG