我正在编写扑克游戏应用程序，并尝试使用以下代码调整屏幕上的卡片位置：
的xml：
<RelativeLayout...>
......
<LinearLayout...>......</LinearLayout>
<LinearLayout...>......</LinearLayout>
<TableLayout...>......</TableLayout>
......
<ImageView
android:layout_width="75dp"
android:layout_height="100dp"
android:id="@+id/assignedCardCenter"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true" />
<ImageView
android:layout_width="75dp"
android:layout_height="100dp"
android:scaleType="centerInside"
android:id="@+id/assignedCardEast"
android:layout_toRightOf="@id/assignedCardCenter"
android:layout_toEndOf="@id/assignedCardCenter"
android:layout_alignBottom="@id/assignedCardCenter" />
<ImageView
android:layout_width="75dp"
android:layout_height="100dp"
android:scaleType="centerInside"
android:id="@+id/assignedCardWest"
android:layout_toLeftOf="@id/assignedCardCenter"
android:layout_toStartOf="@id/assignedCardCenter"
android:layout_alignBottom="@id/assignedCardCenter" />
<ImageView
android:layout_width="75dp"
android:layout_height="100dp"
android:scaleType="centerInside"
android:id="@+id/assignedCardSouth"
android:layout_below="@id/assignedCardCenter"
android:layout_alignLeft="@id/assignedCardCenter"
android:layout_alignStart="@id/assignedCardCenter" />
<ImageView
android:layout_width="75dp"
android:layout_height="100dp"
android:scaleType="centerInside"
android:id="@+id/assignedCardNorth"
android:layout_above="@id/assignedCardCenter"
android:layout_alignLeft="@id/assignedCardCenter"
android:layout_alignStart="@id/assignedCardCenter"
android:src="@drawable/c50"/>
......
</RelativeLayout>
的java：
private ImageView[] assignedCardsOnTable=new ImageView[4];
private int[] assignedCardsOnTableID={R.id.assignedCardEast,R.id.assignedCardSouth,R.id.assignedCardWest,R.id.assignedCardNorth};
//......
@Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
for(int i=0;i<4;i++)
{
assignedCardsOnTable[i]=(ImageView)findViewById(cardsOnTableID[i]);
assignedCardsOnTable[i].setVisibility(View.GONE);
}
//......
SetAssignedCard_DummyHandLayout();
}
//......
private void SetAssignedCard_DummyHandLayout()
{
for(int i=0;i<4;i++)
{
assignedCardsOnTable[i].setVisibility(View.VISIBLE);
}
RelativeLayout.LayoutParams[] cardPosition=new RelativeLayout.LayoutParams[4];
for(int i=0;i<4;i++)
{
//==========THIS IS WHERE THE EXCEPTION OCCURED===========
cardPosition[i]=(RelativeLayout.LayoutParams)assignedCardsOnTable[i].getLayoutParams();
//========================================================
cardPosition[i].addRule(RelativeLayout.RIGHT_OF,0);
cardPosition[i].addRule(RelativeLayout.LEFT_OF,0);
cardPosition[i].addRule(RelativeLayout.ABOVE,0);
cardPosition[i].addRule(RelativeLayout.BELOW,0);
}
if(Contract.dealer=='E')
{
}
else if(Contract.dealer=='W')
{
}
else
{
cardPosition[0].addRule(RelativeLayout.RIGHT_OF,R.id.assignedCardCenter);
cardPosition[0].addRule(RelativeLayout.ALIGN_BOTTOM,R.id.assignedCardCenter);
cardPosition[0].setMargins(5,0,0,0);
cardPosition[1].addRule(RelativeLayout.BELOW,R.id.assignedCardCenter);
cardPosition[1].addRule(RelativeLayout.ALIGN_LEFT,R.id.assignedCardCenter);
cardPosition[1].setMargins(0,5,0,0);
cardPosition[2].addRule(RelativeLayout.LEFT_OF,R.id.assignedCardCenter);
cardPosition[2].addRule(RelativeLayout.ALIGN_BOTTOM,R.id.assignedCardCenter);
cardPosition[2].setMargins(0,0,5,0);
cardPosition[3].addRule(RelativeLayout.ABOVE,R.id.assignedCardCenter);
cardPosition[3].addRule(RelativeLayout.ALIGN_LEFT,R.id.assignedCardCenter);
cardPosition[3].setMargins(0,0,0,5);
}
for(int i=0;i<4;i++)
{
assignedCardsOnTable[i].setLayoutParams(cardPosition[i]);
assignedCardsOnTable[i].setImageResource(cardImageID[50]);
}
}
我的函数java.lang.ClassCastException中发生SetAssignedCard_DummyHandLayout()，这是堆栈跟踪：
java.lang.ClassCastException: android.widget.LinearLayout$LayoutParams cannot be cast to android.widget.RelativeLayout$LayoutParams
at com.einsambr.bridge_0_0_2.MainActivity.SetAssignedCard_DummyHandLayout(MainActivity.java:568)
at com.einsambr.bridge_0_0_2.MainActivity.SetPlayerRevisedAndPlay(MainActivity.java:544)
at com.einsambr.bridge_0_0_2.MainActivity.access$1000(MainActivity.java:21)
at com.einsambr.bridge_0_0_2.MainActivity$1.onClick(MainActivity.java:273)
at android.view.View.performClick(View.java:5198)
at android.view.View$PerformClick.run(View.java:21147)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:5417)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)
问题：根据xml代码，assignedCardsOnTable [i]确实安排在RelativeLayout中，因此，
assignedCardsOnTable[i].getLayoutParams();
应该提出RelativeLayout.LayoutParams。 为什么会发生ClassCastException？我哪里做错了？谢谢你的帮助：）