问题描述
我已经扩展了View以构建自定义窗口小部件。我想用独立像素单位定义小部件的高度。
我认为可以通过将像素密度乘以所需的高度来完成,但是我不知道该怎么做。
I have extended View to build a custom widget. I would like to define the height of the widget with an independ pixel unit.I think it could be done by multiplying the pixel density by the desired height , but i don't know how to do that.
我有什么用远(最小):
What i have so far (minimized) :
public class Timeline extends View
{
@Override
protected void onDraw(Canvas canvas) {
//super.onDraw(canvas);
int canvasWidth = canvas.getWidth();
this.widgetWith = canvasWidth;
this.setBackgroundGradientNoVideo();
RectF rect = new RectF();
rect.set(0, 0, canvasWidth, 50);
//Dessin d'un rectangle de fond
canvas.drawRoundRect(rect, 10, 10, this.paint);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
// TODO Auto-generated method stub
//super.onMeasure(widthMeasureSpec, 50);
this.setMeasuredDimension(widthMeasureSpec, 50);
this.widgetWith = MeasureSpec.getSize(widthMeasureSpec);
}
}
所以我想换行
this.setMeasuredDimension(widthMeasureSpec, 50);
和
rect.set(0, 0, canvasWidth, 50);
要与像素无关。
谢谢
推荐答案
将像素值乘以 getResources()。getDisplayMetrics()。density
使像素密度无关。如果您绘制文本,则可能要改用scaledDensity。
multiply your pixel values by getResources().getDisplayMetrics().density
to make pixels density-independent. If you draw text, you might want to use scaledDensity instead.
我相信密度在mdpi上为1,在hdpi为1.5,在ldpi为0.75。
density = 1 on mdpi, 1.5 on hdpi, and 0.75 on ldpi i believe.
要完成答案,请提供一些源代码:
在处理视图时,请使用以下内容:图片
Either use the following when dealing with views or images
int px = getResources().getDisplayMetrics().density * dp;
或者,在处理文本时:
int px = getResources().getDisplayMetrics().scaledDensity * sp;
这篇关于如何在onDraw()方法中定义像素独立的高度的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持!