Java 错误:指定的子级已具有父级
在我的程序中,我在模拟器上遇到了这个错误如果我在我的Razr MAXX上运行它,它会工作吗?它说Java 错误:指定的子级已具有父级,java,android,layout,view,Java,Android,Layout,View,在我的程序中,我在模拟器上遇到了这个错误如果我在我的Razr MAXX上运行它,它会工作吗?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. 此行出现错误:layout.addView(mid
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.
此行出现错误:layout.addView(mid)
我相信它说mid已经有了一个父级,所以我用ViewGroup parent=(ViewGroup)mid.getParent()进行了调试代码>并返回null
有人能把我引向正确的方向吗
下面是我的班级:
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);
}
}
onDraw()
被Android反复调用。对onDraw()
的第二次调用将引发此异常,因为每个视图都已添加到父视图中
也就是说,作为一项规则,您永远不会更改onDraw()中的布局。此方法仅用于在画布上绘制。即使您通过调用removeAllViews()
(看起来您可能已经尝试过了)来修复此异常,也会迫使Android在视图被删除和重新添加时不断地测量和绘制布局
您可能实际上不想将子视图添加到父视图中。如果要添加子视图,应将其添加为蜂巢视图的子视图
。为此,您需要扩展ViewGroup
,而不是View
。再次,将子视图添加到其他位置,而不是onDraw()
中
虽然将子视图添加到视图组
会起作用,但这对性能不是很好。添加到布局中的每个子视图都会减慢应用程序的速度。(请参阅。)一个更好的选择是使用(例如)Canvas.drawPath()
直接在Canvas
上绘制形状
你想干什么?您不应该在onDraw()
中进行布局,我正在尝试从其他视图(由六边形组成的蜂巢)构建视图,然后将HoneycombView()设置为视图组,或者在onDraw()中绘制六边形。
我尝试在onDraw中绘制六边形,但仍然出现错误。我将尝试查看组。但是,为什么它能在我的手机上工作而不能在模拟器上工作呢?onDraw()
被Android反复调用。对onDraw()
的第二次调用将引发此异常,因为每个视图都已添加到父视图中。