我正在尝试在模拟器中实现垂直SeekBar,但是我有些困惑。我可以让SeekBar以我想要的方式显示,也可以让进度按照我的意愿进行,而且我可以修改onTouchEvent使得thumb在垂直方向而不是水平方向上移动。但我无法使thumb在默认的29个水平像素之外移动而不使用setThumbOffset()。这本身并不是问题,问题在于我完全不理解thumbOffset。我想我可能可以(正确地)调整小部件大小,但我很确定我做得不对。或者,如果我能弄清楚它,我只需使用thumbOffset即可。由于我可以正确计算进度,因此我认为只需将进度*(getTop() - getBottom())的小部件线性函数用于计算,但似乎行不通。但我无法弄清楚偏移量的中心位置在哪里。
作为一个有点离题的问题,我真的不确定我在onSizeChanged()中所做的事情是否合理,或者它是否会在以后给我带来麻烦。
以下是main.xml布局:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent" >
<com.mobilsemantic.mobipoll.SlideBar
android:id="@+id/slide"
android:layout_width="wrap_content"
android:layout_height="fill_parent"
android:max="100"
android:progress="0"
android:secondaryProgress="25" />
<Button android:id="@+id/button"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:text="Hello, I am a Button" />
<TextView android:id="@+id/tracking"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
</LinearLayout>
以下是关于类的代码(忽略调试信息):
import android.content.Context;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;
import android.widget.SeekBar;
public class SlideBar extends SeekBar {
private int oHeight = 320, oWidth = 29;
private int oProgress = -1, oOffset = -1;;
private float xPos = -1, yPos = -1;
private int top = -1, bottom = -1, left = -1, right = -1;
public SlideBar(Context context) {
super(context);
}
public SlideBar(Context context, AttributeSet attrs)
{
super(context, attrs);
oOffset = this.getThumbOffset();
oProgress = this.getProgress();
}
public SlideBar(Context context, AttributeSet attrs, int defStyle)
{
super(context, attrs, defStyle);
}
protected synchronized void onMeasure(int widthMeasureSpec, intheightMeasureSpec)
{
int height = View.MeasureSpec.getSize(heightMeasureSpec);
oHeight = height;
this.setMeasuredDimension(oWidth, oHeight);
}
protected void onSizeChanged(int w, int h, int oldw, int oldh)
{
super.onSizeChanged(h, w, oldw, oldh);
}
protected void onLayout(boolean changed, int l, int t, int r, int b)
{
super.onLayout(changed, l, t, r, b);
left = l;
right = r;
top = t;
bottom = b;
}
protected void onDraw(Canvas c)
{
c.rotate(90);
c.translate(0,-29);
super.onDraw(c);
}
public boolean onTouchEvent(MotionEvent event)
{
xPos = event.getX();
yPos = event.getY();
float progress = (yPos-this.getTop())/(this.getBottom()-this.getTop());
oOffset = this.getThumbOffset();
oProgress = this.getProgress();
Log.d("offset" + System.nanoTime(), new Integer(oOffset).toString());
Log.d("progress" + System.nanoTime(), new Integer(oProgress).toString());
float offset;
offset = progress * (this.getBottom()-this.getTop());
this.setThumbOffset((int)offset);
Log.d("offset_postsetprogress" + System.nanoTime(), new Integer(oOffset).toString());
Log.d("progress_postsetprogress" + System.nanoTime(), new Integer(oProgress).toString());
this.setProgress((int)(100*event.getY()/this.getBottom()));
return true;
}
}