Android: 从中心绘制搜索栏进度

Question

大家好，我目前正在自己工作 Android SeekBar，我想让进度条的颜色从栏的中心绘制到拇指。目前，我的 SeekBar class 看起来像这样：

public class VerticalSeekBar extends SeekBar {

public VerticalSeekBar(Context context) {
    super(context);

}

public VerticalSeekBar(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

}

public VerticalSeekBar(Context context, AttributeSet attrs) {
    super(context, attrs);
    setThumb(getResources().getDrawable(R.drawable.slidera));
    setProgressDrawable(getResources().getDrawable(R.drawable.sl_bg));
}

protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(h, w, oldh, oldw);
}

@Override
protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(heightMeasureSpec, widthMeasureSpec);
    setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
}

protected void onDraw(Canvas c) {

    c.rotate(-90);
    c.translate(-getHeight(), 0);

    super.onDraw(c);
}

@Override
public boolean onTouchEvent(MotionEvent event) {
   [...]

我现在的问题是我不知道我需要重写什么方法来改变 ProgressDrawable 的绘图行为，我相信一定有一些方法。

提前致谢

Answer 1

所以这就是现在的全部 class。 getRekt 方法获取 SeekBar 的大小，您在 onDraw 方法中看到的其他内容几乎是 self-explaining。背景可绘制对象是由颜色值 0x00000000 组成的可绘制对象，因此它不会覆盖 "new" 进度背景。

public class VerticalSeekBar extends SeekBar {

public VerticalSeekBar(Context context) {
    super(context);

}

public VerticalSeekBar(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);

}

public VerticalSeekBar(Context context, AttributeSet attrs) {
    super(context, attrs);
    setThumb(getResources().getDrawable(R.drawable.slidera));
    setThumbOffset(0);
    setProgressDrawable(getResources().getDrawable(R.drawable.sl_bg));

    setPadding(0,0,0,0);
} 

protected void onSizeChanged(int w, int h, int oldw, int oldh) {
    super.onSizeChanged(h, w, oldh, oldw);
}

@Override
protected synchronized void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    super.onMeasure(heightMeasureSpec, widthMeasureSpec);
    setMeasuredDimension(getMeasuredHeight(), getMeasuredWidth());
}

protected void onDraw(Canvas c) {

    c.rotate(-90);
    c.translate(-getHeight(), 0);
    Paint paint = new Paint();
    paint.setColor(0xffff7700);
    paint.setStrokeWidth(11);


    BlurMaskFilter blurMaskFilter=new BlurMaskFilter(15.0f,BlurMaskFilter.Blur.OUTER);
    c.drawLine(
            getRectX()+(getProgress()-50)*getRHeight()/100, getRectY(),getRectX(), getRectY(), paint);
    paint.setMaskFilter(blurMaskFilter);

    c.drawLine(
            getRectX()+(getProgress()-50)*getRHeight()/100, getRectY(),getRectX(), getRectY(), paint);


drawMeter(c);

     super.onDraw(c);

}

public int getRectX(){
Rect MLG=   getProgressDrawable().getBounds();
return MLG.centerX();
}
public int getRectY(){
Rect MLG=   getProgressDrawable().getBounds();
 return MLG.centerY();
}

public int getRHeight(){
Rect MLG=   getProgressDrawable().getBounds();
return MLG.width();
}

public void drawMeter(Canvas c){
Paint paint = new Paint();
paint.setColor(0xffff7700);

 paint.setStrokeWidth(2);      
c.drawLine(
        0,100,0, 0, paint);
c.drawLine(
        getRHeight()/2,100,getRHeight()/2, 0, paint);
c.drawLine(
        getRHeight(),100,getRHeight(), 0, paint);


}

@Override
public boolean onTouchEvent(MotionEvent event) {
    if (!isEnabled()) {
        return false;
    }

    switch (event.getAction()) {
        case MotionEvent.ACTION_DOWN:
        case MotionEvent.ACTION_MOVE:
        case MotionEvent.ACTION_UP:
            setProgress(getMax() - (int) (getMax() * event.getY() / getHeight()));
            onSizeChanged(getWidth(), getHeight(), 0, 0);

            break;

        case MotionEvent.ACTION_CANCEL:
            break;
    }
    return true;
}
}

这应该看起来像这样：

Android: 从中心绘制搜索栏进度

Android: Draw seekbar progress from center

android

android-seekbar