当我尝试将ScrollView添加到LinearLayout应用程序突然终止时，我遇到了问题。
public class DynamicButtonAdd extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Button b1=new Button(getBaseContext());
b1.setText("Button 1");
Button b2=new Button(getBaseContext());
b2.setText("Button 2");
Button b3=new Button(getBaseContext());
b3.setText("Button 3");
Button b4=new Button(getBaseContext());
b4.setText("Button 4");
Button b5=new Button(getBaseContext());
b5.setText("Button 5");
Button b6=new Button(getBaseContext());
b6.setText("Button 6");
Button b7=new Button(getBaseContext());
b7.setText("Button 7");
Button b8=new Button(getBaseContext());
b8.setText("Button 8");
Button b9=new Button(getBaseContext());
b9.setText("Button 9");
Button b10=new Button(getBaseContext());
b10.setText("Button 10");
Button b11=new Button(getBaseContext());
b11.setText("Button 1");
Button b12=new Button(getBaseContext());
b12.setText("Button 12");
TableLayout.LayoutParams l=new TableLayout.LayoutParams();
l.width= l.height=Toolbar.LayoutParams.WRAP_CONTENT;
b1.setLayoutParams(l);
b2.setLayoutParams(l);
b3.setLayoutParams(l);
b4.setLayoutParams(l);
b5.setLayoutParams(l);
b6.setLayoutParams(l);
b7.setLayoutParams(l);
b8.setLayoutParams(l);
b9.setLayoutParams(l);
b10.setLayoutParams(l);
b11.setLayoutParams(l);
b12.setLayoutParams(l);
ScrollView sv=new ScrollView(getBaseContext());
sv.setFillViewport(true);
LinearLayout linear=new LinearLayout(getBaseContext());
sv.addView(linear);// the error appear here if I comment this line works fine without scroll
linear.setOrientation(LinearLayout.VERTICAL);
linear.setGravity(Gravity.CENTER);
linear.addView(b1);
linear.addView(b2);
linear.addView(b3);
linear.addView(b4);
linear.addView(b5);
linear.addView(b6);
linear.addView(b7);
linear.addView(b8);
linear.addView(b9);
linear.addView(b10);
linear.addView(b11);
linear.addView(b12);
setContentView(linear);
b1.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Toast.makeText(getBaseContext(),"Clicked",Toast.LENGTH_SHORT).show();
}
});
}
}
显示的例外：
08-08 16:42:39.140 26674-26674/com.example.sid.test D/AndroidRuntime: Shutting down VM
08-08 16:42:39.140 26674-26674/com.example.sid.test W/dalvikvm: threadid=1: thread exiting with uncaught exception (group=0xb60ab4f0)
08-08 16:42:39.144 26674-26674/com.example.sid.test E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.sid.test/com.example.sid.test.DynamicButtonAdd}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1647)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
at android.app.ActivityThread.access$1500(ActivityThread.java:117)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3683)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
at android.view.ViewGroup.addViewInner(ViewGroup.java:1976)
at android.view.ViewGroup.addView(ViewGroup.java:1871)
at android.view.ViewGroup.addView(ViewGroup.java:1828)
at android.view.ViewGroup.addView(ViewGroup.java:1808)
at android.support.v7.app.AppCompatDelegateImplV7.setContentView(AppCompatDelegateImplV7.java:271)
at android.support.v7.app.AppCompatActivity.setContentView(AppCompatActivity.java:145)
at com.example.sid.test.DynamicButtonAdd.onCreate(DynamicButtonAdd.java:106)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663)
at android.app.ActivityThread.access$1500(ActivityThread.java:117)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:931)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:130)
at android.app.ActivityThread.main(ActivityThread.java:3683)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:507)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
at dalvik.system.NativeStart.main(Native Method)
我对这个程序不感兴趣，如果有任何有用的方案，请告诉我。最低api级别还有一个是8（Android 2.2）。
答案 0 :(得分：1)
您的代码存在一些问题。导致崩溃的原因是您将LinearLayout添加到ScrollView，然后致电setContentView(linear)，即您将LinearLayout添加到您的活动和{{{}} 1}}。您可能希望在内容时设置ScrollView。因此，简单的解决方法是：
ScrollView其次，问题是：
ScrollView sv=new ScrollView(getBaseContext());
sv.setFillViewport(true);
LinearLayout linear=new LinearLayout(getBaseContext());
sv.addView(linear);
...
setContentView(sv); // you have linear here
您要将此TableLayout.LayoutParams l=new TableLayout.LayoutParams();
l.width= l.height=Toolbar.LayoutParams.WRAP_CONTENT;
设置为LayoutParam个实例，这些实例将添加到Button。您应该在此处设置父LinearLayout的布局参数：
ViewGroup第三，我有一点点感觉（我可能错了，因为我不知道真正的用例），你可以将至少部分布局描述移到和xml文件