我创建了这篇文章,因为我是新手,我需要一些帮助。我正在做一个关于你输入你名字的应用程序的小练习,它返回“你好(你输入的名字)”。但是在我按下按钮后,我收到错误“指定的孩子已经有一个父母。你必须先在孩子的父母上调用 removeView()”
MainActivity.java
package com.example.holaamigos;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.*;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends Activity {
public final static String EXTRA_SALUDO = "com.example.holaamigos.SALUDO";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText txtNombre = (EditText)findViewById(R.id.TxtNombre);
final Button btnHola = (Button)findViewById(R.id.BtnHola);
btnHola.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, ActivitySaludo.class);
String saludo = txtNombre.getText().toString();
intent.putExtra(EXTRA_SALUDO, saludo);
startActivity(intent);
}
});
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
ActivitySaludo.java
package com.example.holaamigos;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
public class ActivitySaludo extends Activity {
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_saludo);
Intent intent = getIntent();
String saludo = intent.getStringExtra(MainActivity.EXTRA_SALUDO);
//TextView txt = new TextView(this);
//txt.setText(20);
//txt.setText(saludo);
TextView txtCambiado = (TextView) findViewById(R.id.TxtSaludo);
txtCambiado.setText(saludo);
setContentView(txtCambiado);
}
}
activity_saludo.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/TxtSaludo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="" />
</LinearLayout>
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/LinearLayout1"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<TextView
android:id="@+id/LblNombre"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/nombre" />
<EditText
android:id="@+id/TxtNombre"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:inputType="text" />
<Button
android:id="@+id/BtnHola"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hola_apy"
android:onClick="enviarSaludo"/>
</LinearLayout>
日志猫
10-10 16:12:18.470: D/AndroidRuntime(810): Shutting down VM
10-10 16:12:18.470: W/dalvikvm(810): threadid=1: thread exiting with uncaught exception (group=0x40a71930)
10-10 16:12:18.586: E/AndroidRuntime(810): FATAL EXCEPTION: main
10-10 16:12:18.586: E/AndroidRuntime(810): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.holaamigos/com.example.holaamigos.ActivitySaludo}: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2180)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread.access$600(ActivityThread.java:141)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.os.Handler.dispatchMessage(Handler.java:99)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.os.Looper.loop(Looper.java:137)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread.main(ActivityThread.java:5041)
10-10 16:12:18.586: E/AndroidRuntime(810): at java.lang.reflect.Method.invokeNative(Native Method)
10-10 16:12:18.586: E/AndroidRuntime(810): at java.lang.reflect.Method.invoke(Method.java:511)
10-10 16:12:18.586: E/AndroidRuntime(810): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
10-10 16:12:18.586: E/AndroidRuntime(810): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)
10-10 16:12:18.586: E/AndroidRuntime(810): at dalvik.system.NativeStart.main(Native Method)
10-10 16:12:18.586: E/AndroidRuntime(810): Caused by: java.lang.IllegalStateException: The specified child already has a parent. You must call removeView() on the child's parent first.
10-10 16:12:18.586: E/AndroidRuntime(810): at android.view.ViewGroup.addViewInner(ViewGroup.java:3339)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.view.ViewGroup.addView(ViewGroup.java:3210)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.view.ViewGroup.addView(ViewGroup.java:3186)
10-10 16:12:18.586: E/AndroidRuntime(810): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:289)
10-10 16:12:18.586: E/AndroidRuntime(810): at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:279)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.Activity.setContentView(Activity.java:1901)
10-10 16:12:18.586: E/AndroidRuntime(810): at com.example.holaamigos.ActivitySaludo.onCreate(ActivitySaludo.java:25)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.Activity.performCreate(Activity.java:5104)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1080)
10-10 16:12:18.586: E/AndroidRuntime(810): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2144)
10-10 16:12:18.586: E/AndroidRuntime(810): ... 11 more
10-10 16:12:18.856: D/dalvikvm(810): GC_CONCURRENT freed 134K, 10% free 2630K/2908K, paused 73ms+83ms, total 237ms