单击操作栏菜单按钮导致应用程序停止
Actionbar menu button clicked caused app to stop
我对 android 开发完全陌生。我目前正在尝试制作一个笔记应用程序。操作栏将有 2 个按钮,创建和设置,引导用户创建和设置页面。创建按钮工作得很好,但我不知道为什么每当我 运行 应用程序并单击设置按钮时它不会引导我进入设置页面,应用程序突然停止。
这是我的代码
MainActivity.java
包 com.example.sunny.mynote;
import android.app.ActionBar;
import android.app.ListActivity;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Adapter;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import com.example.sunny.mynote.com.example.sunny.mynote.data.NoteDataSource;
import com.example.sunny.mynote.com.example.sunny.mynote.data.NoteItem;
import java.util.List;
public class MainActivity extends ListActivity {
public static final int EDITOR_ACRIVITY_REQUEST = 1001;
public static final int SETTINGS_REQUEST = 1003;
private static final int MENU_DELETE_ID = 1002;
private int currentNoteId;
private NoteDataSource datasource;
List<NoteItem> notesList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
registerForContextMenu(getListView());
datasource = new NoteDataSource(this);
refreshDisplay();
}
private void refreshDisplay() {
notesList = datasource.findAll();
ArrayAdapter<NoteItem> adapter =
new ArrayAdapter<NoteItem>(this, R.layout.list_item_layout, notesList);
setListAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.action_create)
{
createNote();
}
int id = item.getItemId();
if (id == R.id.action_create) {
return true;
}
if (item.getItemId() == R.id.action_settings)
{
Intent intent2 = new Intent(MainActivity.this, Settings.class);
startActivity(intent2);
}
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void createNote()
{
NoteItem note = NoteItem.getNew();
Intent intent = new Intent(this, NoteEditorActivity.class);
intent.putExtra("key", note.getKey());
intent.putExtra("text", note.getText());
startActivityForResult(intent, EDITOR_ACRIVITY_REQUEST);
}
private void Settings()
{
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
NoteItem note = notesList.get(position);
Intent intent = new Intent(this, NoteEditorActivity.class);
intent.putExtra("key", note.getKey());
intent.putExtra("text", note.getText());
startActivityForResult(intent, EDITOR_ACRIVITY_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == EDITOR_ACRIVITY_REQUEST && resultCode == RESULT_OK)
{
overridePendingTransition(R.anim.fadein, R.anim.fadeout);
NoteItem note = new NoteItem();
note.setKey(data.getStringExtra("key"));
note.setText(data.getStringExtra("text"));
datasource.update(note);
refreshDisplay();
}
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) menuInfo;
currentNoteId = (int)info.id;
menu.add(0, MENU_DELETE_ID, 0, "Delete");
}
@Override
public boolean onContextItemSelected(MenuItem item) {
if (item.getItemId() == MENU_DELETE_ID)
{
NoteItem note = notesList.get(currentNoteId);
datasource.remove(note);
refreshDisplay();
}
return super.onContextItemSelected(item);
}
}
Settings.java
package com.example.sunny.mynote;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.EditText;
/**
* Created by Sunny on 19/04/2015.
*/
public class Settings extends Activity {
View view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
private RadioGroup RadioGroup1;
private RadioButton rdbRed, rdbBlue, rdbOrange;
private Button btnSave;
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.settings);
View view = LayoutInflater.from(getApplication()).inflate(R.layout.settings, null);
RadioGroup1 = (RadioGroup) findViewById(R.id.RadioGroup1);
RadioGroup1.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
if(checkedId == R.id.rdbRed)
{
Toast.makeText(getApplicationContext(), "choice: Red",
Toast.LENGTH_SHORT).show();
}
else if(checkedId == R.id.rdbBlue)
{
Toast.makeText(getApplicationContext(), "choice: Blue",
Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(), "choice: Orange",
Toast.LENGTH_SHORT).show();
}
}
});
Intent intent = new Intent(this, NoteEditorActivity.class);
rdbRed = (RadioButton) findViewById(R.id.rdbRed);
rdbBlue = (RadioButton) findViewById(R.id.rdbBlue);
rdbOrange = (RadioButton) findViewById(R.id.rdbOrange);
textView = (TextView) findViewById(R.id.noteText);
btnSave = (Button)findViewById(R.id.btn_Save);
btnSave.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int selectedId = RadioGroup1.getCheckedRadioButtonId();
if(selectedId == rdbRed.getId()) {
textView.setTextColor(Color.parseColor("#FF0000"));
} else if(selectedId == rdbBlue.getId()) {
textView.setTextColor(Color.parseColor("#0066FF"));
} else {
textView.setTextColor(Color.parseColor("#FF6600"));
}
finish();
}
});
}
@Override
public void onBackPressed() {
finish();
}
}
日志
04-21 22:02:11.583 26636-26636/com.example.sunny.mynote I/SELinux﹕ Function: selinux_android_load_priority [0], There is no sepolicy file.
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote I/SELinux﹕ Function: selinux_android_load_priority , spota verifySig and checkHash pass. priority version is VE=SEPF_SM-N9005_4.4.2_0040
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote I/SELinux﹕ selinux_android_seapp_context_reload: seapp_contexts file is loaded from /data/security/spota/seapp_contexts
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote E/dalvikvm﹕ >>>>> Normal User
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote E/dalvikvm﹕ >>>>> com.example.sunny.mynote [ userId:0 | appId:10383 ]
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote D/dalvikvm﹕ Late-enabling CheckJNI
04-21 22:02:11.613 26636-26636/com.example.sunny.mynote I/dalvikvm﹕ Enabling JNI app bug workarounds for target SDK version 7...
04-21 22:02:11.693 26636-26636/com.example.sunny.mynote W/ApplicationPackageManager﹕ getCSCPackageItemText()
04-21 22:02:11.693 26636-26636/com.example.sunny.mynote I/PersonaManager﹕ getPersonaService() name persona_policy
04-21 22:02:11.723 26636-26636/com.example.sunny.mynote E/MoreInfoHPW_ViewGroup﹕ Parent view is not a TextView
04-21 22:02:11.743 26636-26636/com.example.sunny.mynote D/AbsListView﹕ Get MotionRecognitionManager
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onVisibilityChanged() is called, visibility : 4
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onVisibilityChanged() is called, visibility : 0
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.773 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.793 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.793 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.823 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.868 26636-26636/com.example.sunny.mynote D/AbsListView﹕ Get MotionRecognitionManager
04-21 22:02:12.898 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.948 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.948 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.998 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.998 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onDetachedFromWindow
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AndroidRuntime﹕ Shutting down VM
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x417e0da0)
04-21 22:02:13.768 26636-26636/com.example.sunny.mynote E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.sunny.mynote, PID: 26636
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.sunny.mynote/com.example.sunny.mynote.Settings}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2218)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2350)
at android.app.ActivityThread.access0(ActivityThread.java:163)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1257)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5335)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.view.LayoutInflater.from(LayoutInflater.java:212)
at com.example.sunny.mynote.Settings.<init>(Settings.java:21)
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1208)
at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2350)
at android.app.ActivityThread.access0(ActivityThread.java:163)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1257)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5335)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
04-21 22:02:15.248 26636-26636/com.example.sunny.mynote I/Process﹕ Sending signal. PID: 26636 S
IG: 9
尝试在设置中更改此行:
private View view;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.settings);
view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
}
您必须在内部膨胀视图或更改 OnCreate() 的调用
所以将你的行 View view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
移到 Settings.java
中的 oncreate() 内
我对 android 开发完全陌生。我目前正在尝试制作一个笔记应用程序。操作栏将有 2 个按钮,创建和设置,引导用户创建和设置页面。创建按钮工作得很好,但我不知道为什么每当我 运行 应用程序并单击设置按钮时它不会引导我进入设置页面,应用程序突然停止。
这是我的代码
MainActivity.java
包 com.example.sunny.mynote;
import android.app.ActionBar;
import android.app.ListActivity;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.ContextMenu;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Adapter;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import com.example.sunny.mynote.com.example.sunny.mynote.data.NoteDataSource;
import com.example.sunny.mynote.com.example.sunny.mynote.data.NoteItem;
import java.util.List;
public class MainActivity extends ListActivity {
public static final int EDITOR_ACRIVITY_REQUEST = 1001;
public static final int SETTINGS_REQUEST = 1003;
private static final int MENU_DELETE_ID = 1002;
private int currentNoteId;
private NoteDataSource datasource;
List<NoteItem> notesList;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
registerForContextMenu(getListView());
datasource = new NoteDataSource(this);
refreshDisplay();
}
private void refreshDisplay() {
notesList = datasource.findAll();
ArrayAdapter<NoteItem> adapter =
new ArrayAdapter<NoteItem>(this, R.layout.list_item_layout, notesList);
setListAdapter(adapter);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
public boolean onOptionsItemSelected(MenuItem item) {
if (item.getItemId() == R.id.action_create)
{
createNote();
}
int id = item.getItemId();
if (id == R.id.action_create) {
return true;
}
if (item.getItemId() == R.id.action_settings)
{
Intent intent2 = new Intent(MainActivity.this, Settings.class);
startActivity(intent2);
}
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
private void createNote()
{
NoteItem note = NoteItem.getNew();
Intent intent = new Intent(this, NoteEditorActivity.class);
intent.putExtra("key", note.getKey());
intent.putExtra("text", note.getText());
startActivityForResult(intent, EDITOR_ACRIVITY_REQUEST);
}
private void Settings()
{
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
NoteItem note = notesList.get(position);
Intent intent = new Intent(this, NoteEditorActivity.class);
intent.putExtra("key", note.getKey());
intent.putExtra("text", note.getText());
startActivityForResult(intent, EDITOR_ACRIVITY_REQUEST);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == EDITOR_ACRIVITY_REQUEST && resultCode == RESULT_OK)
{
overridePendingTransition(R.anim.fadein, R.anim.fadeout);
NoteItem note = new NoteItem();
note.setKey(data.getStringExtra("key"));
note.setText(data.getStringExtra("text"));
datasource.update(note);
refreshDisplay();
}
}
@Override
public void onCreateContextMenu(ContextMenu menu, View v, ContextMenu.ContextMenuInfo menuInfo) {
AdapterView.AdapterContextMenuInfo info = (AdapterView.AdapterContextMenuInfo) menuInfo;
currentNoteId = (int)info.id;
menu.add(0, MENU_DELETE_ID, 0, "Delete");
}
@Override
public boolean onContextItemSelected(MenuItem item) {
if (item.getItemId() == MENU_DELETE_ID)
{
NoteItem note = notesList.get(currentNoteId);
datasource.remove(note);
refreshDisplay();
}
return super.onContextItemSelected(item);
}
}
Settings.java
package com.example.sunny.mynote;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.widget.Button;
import android.widget.RadioButton;
import android.widget.RadioGroup;
import android.widget.TextView;
import android.widget.Toast;
import android.widget.EditText;
/**
* Created by Sunny on 19/04/2015.
*/
public class Settings extends Activity {
View view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
private RadioGroup RadioGroup1;
private RadioButton rdbRed, rdbBlue, rdbOrange;
private Button btnSave;
private TextView textView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.settings);
View view = LayoutInflater.from(getApplication()).inflate(R.layout.settings, null);
RadioGroup1 = (RadioGroup) findViewById(R.id.RadioGroup1);
RadioGroup1.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(RadioGroup group, int checkedId) {
if(checkedId == R.id.rdbRed)
{
Toast.makeText(getApplicationContext(), "choice: Red",
Toast.LENGTH_SHORT).show();
}
else if(checkedId == R.id.rdbBlue)
{
Toast.makeText(getApplicationContext(), "choice: Blue",
Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(getApplicationContext(), "choice: Orange",
Toast.LENGTH_SHORT).show();
}
}
});
Intent intent = new Intent(this, NoteEditorActivity.class);
rdbRed = (RadioButton) findViewById(R.id.rdbRed);
rdbBlue = (RadioButton) findViewById(R.id.rdbBlue);
rdbOrange = (RadioButton) findViewById(R.id.rdbOrange);
textView = (TextView) findViewById(R.id.noteText);
btnSave = (Button)findViewById(R.id.btn_Save);
btnSave.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
int selectedId = RadioGroup1.getCheckedRadioButtonId();
if(selectedId == rdbRed.getId()) {
textView.setTextColor(Color.parseColor("#FF0000"));
} else if(selectedId == rdbBlue.getId()) {
textView.setTextColor(Color.parseColor("#0066FF"));
} else {
textView.setTextColor(Color.parseColor("#FF6600"));
}
finish();
}
});
}
@Override
public void onBackPressed() {
finish();
}
}
日志
04-21 22:02:11.583 26636-26636/com.example.sunny.mynote I/SELinux﹕ Function: selinux_android_load_priority [0], There is no sepolicy file.
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote I/SELinux﹕ Function: selinux_android_load_priority , spota verifySig and checkHash pass. priority version is VE=SEPF_SM-N9005_4.4.2_0040
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote I/SELinux﹕ selinux_android_seapp_context_reload: seapp_contexts file is loaded from /data/security/spota/seapp_contexts
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote E/dalvikvm﹕ >>>>> Normal User
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote E/dalvikvm﹕ >>>>> com.example.sunny.mynote [ userId:0 | appId:10383 ]
04-21 22:02:11.603 26636-26636/com.example.sunny.mynote D/dalvikvm﹕ Late-enabling CheckJNI
04-21 22:02:11.613 26636-26636/com.example.sunny.mynote I/dalvikvm﹕ Enabling JNI app bug workarounds for target SDK version 7...
04-21 22:02:11.693 26636-26636/com.example.sunny.mynote W/ApplicationPackageManager﹕ getCSCPackageItemText()
04-21 22:02:11.693 26636-26636/com.example.sunny.mynote I/PersonaManager﹕ getPersonaService() name persona_policy
04-21 22:02:11.723 26636-26636/com.example.sunny.mynote E/MoreInfoHPW_ViewGroup﹕ Parent view is not a TextView
04-21 22:02:11.743 26636-26636/com.example.sunny.mynote D/AbsListView﹕ Get MotionRecognitionManager
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onVisibilityChanged() is called, visibility : 4
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onVisibilityChanged() is called, visibility : 0
04-21 22:02:11.763 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.773 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.793 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.793 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:11.823 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.868 26636-26636/com.example.sunny.mynote D/AbsListView﹕ Get MotionRecognitionManager
04-21 22:02:12.898 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.948 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.948 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.998 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:12.998 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ onDetachedFromWindow
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AbsListView﹕ unregisterIRListener() is called
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote D/AndroidRuntime﹕ Shutting down VM
04-21 22:02:13.758 26636-26636/com.example.sunny.mynote W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x417e0da0)
04-21 22:02:13.768 26636-26636/com.example.sunny.mynote E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.sunny.mynote, PID: 26636
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.sunny.mynote/com.example.sunny.mynote.Settings}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2218)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2350)
at android.app.ActivityThread.access0(ActivityThread.java:163)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1257)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5335)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at android.view.LayoutInflater.from(LayoutInflater.java:212)
at com.example.sunny.mynote.Settings.<init>(Settings.java:21)
at java.lang.Class.newInstanceImpl(Native Method)
at java.lang.Class.newInstance(Class.java:1208)
at android.app.Instrumentation.newActivity(Instrumentation.java:1079)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2209)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2350)
at android.app.ActivityThread.access0(ActivityThread.java:163)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1257)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:157)
at android.app.ActivityThread.main(ActivityThread.java:5335)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1265)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1081)
at dalvik.system.NativeStart.main(Native Method)
04-21 22:02:15.248 26636-26636/com.example.sunny.mynote I/Process﹕ Sending signal. PID: 26636 S
IG: 9
尝试在设置中更改此行:
private View view;
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.settings);
view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
}
您必须在内部膨胀视图或更改 OnCreate() 的调用
所以将你的行 View view = LayoutInflater.from(getApplication()).inflate(R.layout.activity_note_editor, null);
移到 Settings.java