在我的程序中,我在模拟器上出现此错误。 如果我在我的Razr MAXX上运行它可以吗?它说
10-28 19:38:27.935: E/AndroidRuntime(2268): java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
此行发生错误:layout.addView(mid)
我相信它说mid已经有了父级,所以我用ViewGroup parent = (ViewGroup) mid.getParent();
进行了调试,它返回null ...
有人可以带领我朝正确的方向前进吗?
以下是我的课程:
package com.example.draganddroptest;
import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.PointF;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
/**
* @author Brandon Ling
*
*/
public class HoneycombView extends View {
private Context context;
private ViewGroup layout;
private HexagonView top;
private HexagonView topRight;
private HexagonView topLeft;
private HexagonView bot;
private HexagonView botLeft;
private HexagonView botRight;
private HexagonView mid;
private int radius;
private PointF shift;
private String color;
private String[] colors;
private int strokeWidth;
Paint paint = new Paint();
/**
* @param context
* @param layout
*/
public HoneycombView(Context context, AttributeSet attrs) {
this(context, null, 0, null, null, attrs, 0);
}
public HoneycombView(Context context, ViewGroup layout, int radius, PointF shift, String color, AttributeSet attrs, int strokeWidth) {
super(context);
this.context = context;
if (attrs != null) { // probably sent via xml
TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.HoneycombView);
this.radius = a.getInt(R.styleable.HoneycombView_radius, this.strokeWidth);
this.shift = new PointF(a.getInt(R.styleable.HoneycombView_shiftX, 0), a.getInt(
R.styleable.HoneycombView_shiftY, 0));
this.colors = a.getString(R.styleable.HoneycombView_hexColors).split("\\|");
a.recycle();
} else {
this.layout = layout;
this.radius = radius;
this.shift = shift;
this.color = color;
}
this.mid = new HexagonView(this.context, null, this.radius, this.shift, this.colors[0], 10);
this.top = mid.addHexTop(colors[1]);
this.topRight = mid.addHexTopRight(colors[2]);
this.topLeft = mid.addHexTopLeft(colors[3]);
this.bot = mid.addHexBot(colors[4]);
this.botRight = mid.addHexBotRight(colors[5]);
this.botLeft = mid.addHexBotLeft(colors[6]);
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
this.layout = (ViewGroup) this.getParent();
ViewGroup parent = (ViewGroup) mid.getParent();
//parent.removeAllViews();
layout.addView(mid);
layout.addView(top);
layout.addView(topRight);
layout.addView(topLeft);
layout.addView(bot);
layout.addView(botRight);
layout.addView(botLeft);
}
@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
int height = (int) Math.ceil(this.bot.getMaxY()) + this.strokeWidth;
int width = (int) Math.ceil(this.botRight.getMaxX()) + this.strokeWidth;
setMeasuredDimension(width, height);
}
}
答案 0 :(得分:1)
onDraw()
。对onDraw()
的第二次调用将抛出此异常,因为每个View
已添加到父级。
也就是说,您通常不会更改onDraw()
内的布局。此方法仅适用于Canvas
。即使你设法通过调用removeAllViews()
来修复此异常(因为它看起来你可能已经尝试过),你将强制Android在删除并重新添加视图时连续测量并再次绘制布局。 / p>
您可能实际上并不想将您的子视图添加到父级。如果要添加子视图,则应将其添加为HoneyCombView
的子视图。为此,您需要扩展ViewGroup
而不是View
。再次,在其他地方添加子视图,而不是onDraw()
。
虽然向ViewGroup
添加子视图会起作用,但它对性能不是很好。您添加到布局的每个子视图都会降低应用程序的速度。 (请参阅Use Fewer Views。)更好的选择是使用(例如)Canvas
直接在canvas.drawPath()
上绘制形状。