我多次尝试使用developer.android(https://developer.android.com/training/basics/firstapp/index.html)上的MyFirstApp教程制作应用程序。我正在使用Stock Android 4.4.2的Nexus 4设备上测试我的代码
我的问题是每次按下发送按钮并且DisplayMessageActivity开始时应用程序崩溃。本教程应用程序崩溃的最常见原因是DisplayMessageActivity未包含在Android Manifest文件中,但它绝对包含在我的文件中。我不知道导致这次崩溃的原因,所以这里是我的完整代码,包括Logcat。
的AndroidManifest.xml:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myfirstapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.myfirstapp.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="@string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.myfirstapp.MainActivity" />
</activity>
</application>
MainActivity.java
package com.example.myfirstapp;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.EditText;
public class MainActivity extends ActionBarActivity {
public final static String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
@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;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container,
false);
return rootView;
}
}
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.enter_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE,message);
startActivity(intent);
}
}
DisplayMessageActivity.java
package com.example.myfirstapp;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v7.app.ActionBarActivity;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
public class DisplayMessageActivity extends ActionBarActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
setContentView(textView);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.display_message, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_display_message,
container, false);
return rootView;
}
}
}
activity_main.xml中
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
tools:context="com.example.myfirstapp.MainActivity"
tools:ignore="MergeRootFrame" >
<EditText
android:id="@+id/enter_message"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="@string/enter_message"/>
<Button
android:id="@+id/button_send"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/button_send"
android:onClick="sendMessage"/>
</LinearLayout>
fragment_main.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.myfirstapp.MainActivity$PlaceholderFragment" >
</RelativeLayout>
activity_display_message.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/container"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context="com.example.myfirstapp.DisplayMessageActivity"
tools:ignore="MergeRootFrame" />
fragment_display_message.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.myfirstapp.DisplayMessageActivity$PlaceholderFragment" >
</RelativeLayout>
logcat的
03-18 15:27:35.195: E/AndroidRuntime(12382): FATAL EXCEPTION: main
03-18 15:27:35.195: E/AndroidRuntime(12382): Process: com.example.myfirstapp, PID: 12382
03-18 15:27:35.195: E/AndroidRuntime(12382): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.myfirstapp/com.example.myfirstapp.DisplayMessageActivity}: java.lang.IllegalArgumentException: No view found for id 0x7f05003c (com.example.myfirstapp:id/container) for fragment PlaceholderFragment{41e7f580 #0 id=0x7f05003c}
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread.access$800(ActivityThread.java:135)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.os.Handler.dispatchMessage(Handler.java:102)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.os.Looper.loop(Looper.java:136)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread.main(ActivityThread.java:5017)
03-18 15:27:35.195: E/AndroidRuntime(12382): at java.lang.reflect.Method.invokeNative(Native Method)
03-18 15:27:35.195: E/AndroidRuntime(12382): at java.lang.reflect.Method.invoke(Method.java:515)
03-18 15:27:35.195: E/AndroidRuntime(12382): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-18 15:27:35.195: E/AndroidRuntime(12382): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
03-18 15:27:35.195: E/AndroidRuntime(12382): at dalvik.system.NativeStart.main(Native Method)
03-18 15:27:35.195: E/AndroidRuntime(12382): Caused by: java.lang.IllegalArgumentException: No view found for id 0x7f05003c (com.example.myfirstapp:id/container) for fragment PlaceholderFragment{41e7f580 #0 id=0x7f05003c}
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:919)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1467)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:570)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1171)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.Activity.performStart(Activity.java:5241)
03-18 15:27:35.195: E/AndroidRuntime(12382): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2168)
03-18 15:27:35.195: E/AndroidRuntime(12382): ... 11 more
如果有人能够发现导致崩溃的错误并且可以帮我解决EditText,那将会很棒。非常感谢。
答案 0 :(得分:1)
你的问题在这里(DisplayMessageActivity
):
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
setContentView(textView);
if (savedInstanceState == null) {
getSupportFragmentManager().beginTransaction()
.add(R.id.container, new PlaceholderFragment()).commit();
}
}
您正在尝试将Fragment
添加到R.id.container
,而Activity'
不属于TextView
视图层次结构的一部分,因为它包含的唯一内容是{{1}} < / p>