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Android 防止在Eclipse图形布局预览中执行代码_Android_Eclipse_Nullpointerexception_Draw_Graphic - Fatal编程技术网

Android 防止在Eclipse图形布局预览中执行代码

Android 防止在Eclipse图形布局预览中执行代码,android,eclipse,nullpointerexception,draw,graphic,Android,Eclipse,Nullpointerexception,Draw,Graphic,我想绘制一个自定义视图,该视图具有绘制方法: @Override public void onDraw(Canvas canvas) { paint.setStyle(Paint.Style.FILL); canvas.drawColor(Color.WHITE); paint.setColor(Color.RED); if(!path.isEmpty()) canvas.drawPath(path, paint); } 在Eclipse图

我想绘制一个自定义视图,该视图具有绘制方法:

@Override 
public void onDraw(Canvas canvas) { 
    paint.setStyle(Paint.Style.FILL);
    canvas.drawColor(Color.WHITE);
    paint.setColor(Color.RED);
    if(!path.isEmpty())
        canvas.drawPath(path, paint);
} 
在Eclipse图形布局预览中,我得到一个NullPointerException。(当然,因为图形布局预览路径为空)。是否有任何方法(例如使用@或其他指令)阻止图形布局预览执行

canvas.drawPath(path, paint);
试试这个

@Override 
public void onDraw(Canvas canvas) { 
    paint.setStyle(Paint.Style.FILL);
    canvas.drawColor(Color.WHITE);
    paint.setColor(Color.RED);
    if(path != null && !path.isEmpty())
        canvas.drawPath(path, paint);
} 

我已经找到了解决方案——对于图形布局,paint也是空的,因为它只转到onDraw()方法,没有看到任何其他内容。谢谢你的帮助。