android 打造不同的Seekbar

最近项目需要用到双向的seekbar，网上找了好多野不能达到要求，偶然一次机会看到了大众点评的例子，然后我最他做了优化，并对常用的seekbar做了总结.

向上两张图：





比如双向seekbar

public class SimpleRangeSeekBar extends View {

private int lineWidth = 5;
private int textSize = 25;

private int inRangeColor = 0xff26b5f5;
private int outRangeColor = 0xffC2C2C2;
private int textColor = 0xff0000ff;

private int textMarginBottom = 10;
private int lowerCenterX;
private int upperCenterX;

private int bmpWidth;
private int bmpHeight;

private Bitmap lowerBmp;
private Bitmap upperBmp;

private boolean isLowerMoving = false;
private boolean isUpperMoving = false;

private OnRangeChangedListener onRangeChangedListener;

private int paddingLeft = 50;
private int paddingRight = 50;
private int paddingTop = 10;
private int paddingBottom = 10;

private int lineHeight=20;
private int lineLength = Utils.getScreenWidth(getContext())-paddingLeft-paddingRight-50;
private int lineStart = paddingLeft;
private int lineEnd = lineLength + paddingLeft;

private int smallRange = 0;
private int maxRange = 100;

private int textHeight;

public SimpleRangeSeekBar(Context context, AttributeSet attrs) {
this(context, attrs,-1);
}

public SimpleRangeSeekBar(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
init(context, attrs, defStyle);
}

private void init(Context context, AttributeSet attrs, int defStyle) {
initAttr(context, attrs, defStyle);
initView();
}

private void initView() {
lowerBmp = BitmapFactory.decodeResource(getResources(),
R.drawable.seekbar_n);
upperBmp = BitmapFactory.decodeResource(getResources(),
R.drawable.seekbar_n);
bmpWidth = upperBmp.getWidth();
bmpHeight = upperBmp.getHeight();

lowerCenterX = lineStart;
upperCenterX = lineEnd;

lineHeight = getHeight() - paddingBottom - lowerBmp.getHeight() / 2;
textHeight = lineHeight + lowerBmp.getHeight() / 2 + 10;
}

private void initAttr(Context context, AttributeSet attrs, int defStyle) {
TypedArray typedArray = getContext().obtainStyledAttributes(attrs, R.styleable.RangeSeekBar, defStyle, 0);
//        lineWidth = typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_layout_width, UIUtils.getScreenWidth(getContext())-paddingLeft-paddingRight-50);
//        lineHeight=typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_layout_height,15);

paddingLeft = typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_paddingLeft, 50);
paddingRight= typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_paddingRight, 50);
paddingTop= typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_paddingTop, 30);
paddingBottom= typedArray.getDimensionPixelSize(R.styleable.RangeSeekBar_paddingBottom, 20);

smallRange = typedArray.getInt(R.styleable.RangeSeekBar_line_small_range,0);
maxRange = typedArray.getInt(R.styleable.RangeSeekBar_line_max_range,100);
typedArray.recycle();
}

private int measureWidth(int measureSpec) {
int result = 0;
int specMode = MeasureSpec.getMode(measureSpec);
int specSize = MeasureSpec.getSize(measureSpec);
if (specMode == MeasureSpec.EXACTLY) {
result = specSize;
} else {
result = paddingLeft + paddingRight + bmpWidth * 2;
if (specMode == MeasureSpec.AT_MOST) {
result = Math.min(result, specSize);
}
}
return result;
}

private int measureHeight(int measureHeight) {
int result = 0;

int specMode = MeasureSpec.getMode(measureHeight);
int specSize = MeasureSpec.getSize(measureHeight);

if (specMode == MeasureSpec.EXACTLY) {
result = bmpHeight * 2;
} else {
result = bmpHeight + paddingTop;
if (specMode == MeasureSpec.AT_MOST) {
result = Math.min(result, specSize);
}
}
return result;
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
widthMeasureSpec = measureWidth(widthMeasureSpec);
heightMeasureSpec = measureHeight(heightMeasureSpec);
setMeasuredDimension(widthMeasureSpec, heightMeasureSpec);
}

@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);

bmpWidth = upperBmp.getWidth();
bmpHeight = upperBmp.getHeight();
lineHeight = getHeight() - paddingBottom - lowerBmp.getHeight() / 2;
textHeight = lineHeight - bmpHeight / 2 - textMarginBottom;
// 画线
Paint linePaint = new Paint();
linePaint.setAntiAlias(true);
linePaint.setStrokeWidth(lineWidth);
// 绘制处于图片滑块之间线段
linePaint.setColor(inRangeColor);
canvas.drawLine(lowerCenterX, lineHeight, upperCenterX, lineHeight,
linePaint);
// 绘制处于图片滑块两端的线段
linePaint.setColor(outRangeColor);
canvas.drawLine(lineStart, lineHeight, lowerCenterX, lineHeight,
linePaint);
canvas.drawLine(upperCenterX, lineHeight, lineEnd, lineHeight,
linePaint);
// 画图片滑块
Paint bmpPaint = new Paint();
canvas.drawBitmap(lowerBmp, lowerCenterX - bmpWidth / 2, lineHeight
- bmpHeight / 2, bmpPaint);
canvas.drawBitmap(lowerBmp, upperCenterX - bmpWidth / 2, lineHeight
- bmpHeight / 2, bmpPaint);

// 画范围文字
drawText(canvas);
}

private void drawText(Canvas canvas) {
Paint textPaint = new Paint();
textPaint.setColor(textColor);
textPaint.setTextSize(textSize);
textPaint.setAntiAlias(true);
textPaint.setStrokeWidth(lineWidth);
canvas.drawText(String.valueOf(smallRange), lowerCenterX
- bmpWidth / 2, textHeight, textPaint);
canvas.drawText(String.valueOf(maxRange), upperCenterX
- bmpWidth / 2, textHeight, textPaint);
}

@Override
public boolean onTouchEvent(MotionEvent event) {
super.onTouchEvent(event);

float xPos = event.getX();
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
// 如果按下的位置在垂直方向没有与图片接触，则不会滑动滑块
float yPos = event.getY();
if (Math.abs(yPos - lineHeight) > bmpHeight / 2) {
return false;
}
// 表示当前按下的滑块是左边的滑块
if (Math.abs(xPos - lowerCenterX) < bmpWidth / 2) {
isLowerMoving = true;
}

// //表示当前按下的滑块是右边的滑块
if (Math.abs(xPos - upperCenterX) < bmpWidth / 2) {
isUpperMoving = true;
}

// 单击左边滑块的左边线条时，左边滑块滑动到对应的位置
if (xPos >= lineStart && xPos <= lowerCenterX - bmpWidth / 2) {
lowerCenterX = (int) xPos;
updateRange();
postInvalidate();
}

// 单击右边滑块的右边线条时， 右边滑块滑动到对应的位置
if (xPos <= lineEnd && xPos >= upperCenterX + bmpWidth / 2) {
upperCenterX = (int) xPos;
updateRange();
postInvalidate();
}
break;
case MotionEvent.ACTION_MOVE:
if (isLowerMoving) {
if (xPos >= lineStart && xPos < upperCenterX - bmpWidth) {
lowerCenterX = (int) xPos;
updateRange();
postInvalidate();
}
}
if (isUpperMoving) {
if (xPos > lowerCenterX + bmpWidth && xPos < lineEnd) {
upperCenterX = (int) xPos;
updateRange();
postInvalidate();
}
}

break;
case MotionEvent.ACTION_UP:
isLowerMoving = false;
isUpperMoving = false;
break;
default:
break;
}

return true;
}

private int computeRange(int range) {
return (range - lineStart) * (maxRange - smallRange) / lineLength
+ smallRange;
}

private void updateRange() {
smallRange = computeRange(lowerCenterX);
maxRange = computeRange(upperCenterX);

if (null != onRangeChangedListener) {
onRangeChangedListener.onRangeChanged(smallRange, maxRange);
}
}

public void setOnRangeChangedListener(
OnRangeChangedListener onRangeChangedListener) {
this.onRangeChangedListener = onRangeChangedListener;
}

public interface OnRangeChangedListener {
void onRangeChanged(int lowRange, int maxRange);
}
}

为了方便大家使用我使用了自定义属性方便大家配置。

大家有兴趣还是去我的链接下载吧
http://download.csdn.net/detail/xiangzhihong8/9578539