问题描述
我知道出现在次论坛上亿这个错误,但请帮我找到我错过了。我试图做简单的标签朝向的应用程序,我没有太多的(除非错误)
1)我的主要活动是基于tablayout教程中我发现了什么
公共类MainTabPanel扩展TabActivity {
公共无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.mainlayout);
资源RES = getResources();
TabHost tabHost = getTabHost();
TabHost.TabSpec规范;
意向意图;
意图=新的意图()setClass(这一点,MyBookActivity.class)。
规格= tabHost.newTabSpec(主)
.setIndicator(主,res.getDrawable(R.drawable.ic_mybook))
.setContent(意向);
tabHost.addTab(规范);
tabHost.setCurrentTab(0);
}
}
2)mainlayout.xml
< XML版本=1.0编码=UTF-8&GT?;
< TabHost的xmlns:机器人=http://schemas.android.com/apk/res/android
机器人:ID =@机器人:ID / tabhost
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT>
<的LinearLayout
机器人:方向=垂直
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT
机器人:填充=5DP>
< TabWidget
机器人:ID =@机器人:ID /标签
机器人:layout_width =FILL_PARENT
机器人:layout_height =WRAP_CONTENT/>
<的FrameLayout
机器人:ID =@机器人:ID / tabcontent
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT
机器人:填充=5DP/>
< / LinearLayout中>< / TabHost>
3)我的第二个活动是基本上几乎是空的,它,只是显示当前的日期和时间,工作之前,我尝试添加标签面板
4)我的清单文件
< XML版本=1.0编码=UTF-8&GT?;
<舱单的xmlns:机器人=http://schemas.android.com/apk/res/android
包=org.th.mybook
安卓版code =1
机器人:VERSIONNAME =1.0>
<使用-SDK安卓的minSdkVersion =8/>
<应用
机器人:图标=@可绘制/ ic_launcher
机器人:标签=@字符串/ APP_NAME>
<活动
机器人:名称=。MainTabPanel
机器人:标签=@字符串/ APP_NAME>
<意向滤光器>
<作用机器人:名称=android.intent.action.MAIN/>
<类机器人:名称=android.intent.category.LAUNCHER/>
&所述; /意图滤光器>
< /活性GT;
<活动
机器人:名称=MyBookActivity
机器人:标签=@字符串/ APP_NAME>
<意向滤光器>
<作用机器人:名称=android.intent.action.MAIN/>
<类机器人:名称=android.intent.category.ALTERNATIVE/>
&所述; /意图滤光器>
< /活性GT;
< /用途>
< /舱单>
5日志猫误差
02-10 21:04:45.203:E / AndroidRuntime(1107):致命异常:主要
02-10 21:04:45.203:E / AndroidRuntime(1107):java.lang.RuntimeException的:无法启动的活动ComponentInfo {org.th.mybook / org.th.mybook.MainTabPanel}:java.lang.RuntimeException的:无法实例活动ComponentInfo {org.th.mybook / org.th.mybook.MyBookActivity}:显示java.lang.NullPointerException
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.access $ 2300(ActivityThread.java:125)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread $ H.handleMessage(ActivityThread.java:2033)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.os.Handler.dispatchMessage(Handler.java:99)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.os.Looper.loop(Looper.java:123)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.main(ActivityThread.java:4627)
02-10 21:04:45.203:E / AndroidRuntime(1107):在java.lang.reflect.Method.invokeNative(本机方法)
02-10 21:04:45.203:E / AndroidRuntime(1107):在java.lang.reflect.Method.invoke(Method.java:521)
02-10 21:04:45.203:E / AndroidRuntime(1107):在com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:868)
02-10 21:04:45.203:E / AndroidRuntime(1107):在com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
02-10 21:04:45.203:E / AndroidRuntime(1107):在dalvik.system.NativeStart.main(本机方法)
02-10 21:04:45.203:E / AndroidRuntime(1107):java.lang.RuntimeException的:产生的原因无法实例活动ComponentInfo {org.th.mybook / org.th.mybook.MyBookActivity}:java.lang中。空指针异常
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.startActivityNow(ActivityThread.java:2503)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.LocalActivityManager.moveToState(LocalActivityManager.java:127)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.LocalActivityManager.startActivity(LocalActivityManager.java:339)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.widget.TabHost $ IntentContentStrategy.getContentView(TabHost.java:651)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.widget.TabHost.setCurrentTab(TabHost.java:323)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.widget.TabHost.addTab(TabHost.java:213)
02-10 21:04:45.203:E / AndroidRuntime(1107):在org.th.mybook.MainTabPanel.onCreate(MainTabPanel.java:30)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
02-10 21:04:45.203:E / AndroidRuntime(1107):11 ...更多
02-10 21:04:45.203:E / AndroidRuntime(1107):由:显示java.lang.NullPointerException
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:100)
02-10 21:04:45.203:E / AndroidRuntime(1107):在org.th.mybook.MyBookActivity< INIT>(MyBookActivity.java:16)
02-10 21:04:45.203:E / AndroidRuntime(1107):在java.lang.Class.newInstanceImpl(本机方法)
02-10 21:04:45.203:E / AndroidRuntime(1107):在java.lang.Class.newInstance(Class.java:1429)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.Instrumentation.newActivity(Instrumentation.java:1021)
02-10 21:04:45.203:E / AndroidRuntime(1107):在android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
02-10 21:04:45.203:E / AndroidRuntime(1107):20 ...更多
请帮帮我,告诉我什么,我错过了,即时通讯比较这code和我的老之一,我无法找到任何东西关于
6)我的书的活动
公共类MyBookActivity延伸活动{
java.text.DateFormat中DATEFORMAT = android.text.format.DateFormat.getDateFormat(getApplicationContext());
@覆盖
公共无效的onCreate(包savedInstanceState){
super.onCreate(savedInstanceState);
的setContentView(R.layout.main);
DigitalClock时钟=(DigitalClock)findViewById(R.id.digitalClock1);
最后的TextView日期=(TextView中)findViewById(R.id.textView1);
date.setText(dateFormat.format(新日期()));
TextWatcher观察家=新TextWatcher(){
@覆盖
公共无效afterTextChanged(编辑S){
}
@覆盖
公共无效beforeTextChanged(CharSequence中,诠释开始,诠释计数,
之后INT){
}
@覆盖
公共无效onTextChanged(CharSequence中,诠释开始,诠释之前,
诠释计数){
如果(s.toString()。startsWith(00:00:00)
|| s.toString()。startsWith(12点○○分00秒)){
date.setText(dateFormat.format(新日期()));
}
}
};
clock.addTextChangedListener(守望者);
}
}
7)main.xml中的布局 - >我的书的活动
< XML版本=1.0编码=UTF-8&GT?;
< LinearLayout中的xmlns:机器人=http://schemas.android.com/apk/res/android
机器人:layout_width =FILL_PARENT
机器人:layout_height =FILL_PARENT
机器人:重力=右
机器人:方向=横向>
<的LinearLayout
机器人:ID =@ + ID / DatePanel1
机器人:layout_width =WRAP_CONTENT
机器人:layout_height =WRAP_CONTENT>
<的TextView
机器人:ID =@ + ID / textView1
机器人:layout_width =match_parent
机器人:layout_height =WRAP_CONTENT
机器人:layout_marginRight =@扪/空间
机器人:layout_weight =1
机器人:文本=TextView的/>
< DigitalClock
机器人:ID =@ + ID / digitalClock1
机器人:layout_width =0dp
机器人:layout_height =WRAP_CONTENT
机器人:layout_weight =1
机器人:文本=DigitalClock/>
< / LinearLayout中>
< / LinearLayout中>
<活动
机器人:名称=MyBookActivity
机器人:标签=@字符串/ APP_NAME>
<意向滤光器>
<作用机器人:名称=android.intent.action.MAIN/>
<类机器人:名称=android.intent.category.ALTERNATIVE/>
&所述; /意图滤光器>
< /活性GT;
在哪里MyBookActivity之前,你点?
I know this error appeared on forum million of times, but please help me find what I missed.I'm trying to do simple tab orientated application,I don't have much (except errors)
1) my main activity is based on tablayout tutorial what I found
public class MainTabPanel extends TabActivity {
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainlayout);
Resources res = getResources();
TabHost tabHost = getTabHost();
TabHost.TabSpec spec;
Intent intent;
intent = new Intent().setClass(this, MyBookActivity.class);
spec = tabHost.newTabSpec("main")
.setIndicator("Main", res.getDrawable(R.drawable.ic_mybook))
.setContent(intent);
tabHost.addTab(spec);
tabHost.setCurrentTab(0);
}
}
2) mainlayout.xml
<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@android:id/tabhost"
android:layout_width="fill_parent"
android:layout_height="fill_parent">
<LinearLayout
android:orientation="vertical"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp">
<TabWidget
android:id="@android:id/tabs"
android:layout_width="fill_parent"
android:layout_height="wrap_content" />
<FrameLayout
android:id="@android:id/tabcontent"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="5dp" />
</LinearLayout></TabHost>
3) my second activity is basically almost empty, it;s just display current date and time, worked before I tried to add tab panel
4) my manifest file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="org.th.mybook"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="8" />
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name=".MainTabPanel"
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="MyBookActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.ALTERNATIVE" />
</intent-filter>
</activity>
</application>
</manifest>
5 log cat error
02-10 21:04:45.203: E/AndroidRuntime(1107): FATAL EXCEPTION: main
02-10 21:04:45.203: E/AndroidRuntime(1107): java.lang.RuntimeException: Unable to start activity ComponentInfo{org.th.mybook/org.th.mybook.MainTabPanel}: java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{org.th.mybook/org.th.mybook.MyBookActivity}: java.lang.NullPointerException
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.os.Handler.dispatchMessage(Handler.java:99)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.os.Looper.loop(Looper.java:123)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.main(ActivityThread.java:4627)
02-10 21:04:45.203: E/AndroidRuntime(1107): at java.lang.reflect.Method.invokeNative(Native Method)
02-10 21:04:45.203: E/AndroidRuntime(1107): at java.lang.reflect.Method.invoke(Method.java:521)
02-10 21:04:45.203: E/AndroidRuntime(1107): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
02-10 21:04:45.203: E/AndroidRuntime(1107): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
02-10 21:04:45.203: E/AndroidRuntime(1107): at dalvik.system.NativeStart.main(Native Method)
02-10 21:04:45.203: E/AndroidRuntime(1107): Caused by: java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{org.th.mybook/org.th.mybook.MyBookActivity}: java.lang.NullPointerException
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.startActivityNow(ActivityThread.java:2503)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.LocalActivityManager.moveToState(LocalActivityManager.java:127)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.LocalActivityManager.startActivity(LocalActivityManager.java:339)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:651)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.widget.TabHost.setCurrentTab(TabHost.java:323)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.widget.TabHost.addTab(TabHost.java:213)
02-10 21:04:45.203: E/AndroidRuntime(1107): at org.th.mybook.MainTabPanel.onCreate(MainTabPanel.java:30)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2627)
02-10 21:04:45.203: E/AndroidRuntime(1107): ... 11 more
02-10 21:04:45.203: E/AndroidRuntime(1107): Caused by: java.lang.NullPointerException
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:100)
02-10 21:04:45.203: E/AndroidRuntime(1107): at org.th.mybook.MyBookActivity.<init>(MyBookActivity.java:16)
02-10 21:04:45.203: E/AndroidRuntime(1107): at java.lang.Class.newInstanceImpl(Native Method)
02-10 21:04:45.203: E/AndroidRuntime(1107): at java.lang.Class.newInstance(Class.java:1429)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
02-10 21:04:45.203: E/AndroidRuntime(1107): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
02-10 21:04:45.203: E/AndroidRuntime(1107): ... 20 more
please help me, and tell me what i missed, im comparing this code with my old one and i can't find anythingregards
6) my book activity
public class MyBookActivity extends Activity {
java.text.DateFormat dateFormat = android.text.format.DateFormat.getDateFormat(getApplicationContext());
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
DigitalClock clock = (DigitalClock) findViewById(R.id.digitalClock1);
final TextView date = (TextView) findViewById(R.id.textView1);
date.setText(dateFormat.format(new Date()));
TextWatcher watcher = new TextWatcher() {
@Override
public void afterTextChanged(Editable s) {
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,
int after) {
}
@Override
public void onTextChanged(CharSequence s, int start, int before,
int count) {
if (s.toString().startsWith("00:00:00")
|| s.toString().startsWith("12:00:00")) {
date.setText(dateFormat.format(new Date()));
}
}
};
clock.addTextChangedListener(watcher);
}
}
7) main.xml layout -> for my book activity
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:gravity="right"
android:orientation="horizontal" >
<LinearLayout
android:id="@+id/DatePanel1"
android:layout_width="wrap_content"
android:layout_height="wrap_content" >
<TextView
android:id="@+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginRight="@dimen/space"
android:layout_weight="1"
android:text="TextView" />
<DigitalClock
android:id="@+id/digitalClock1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_weight="1"
android:text="DigitalClock" />
</LinearLayout>
</LinearLayout>
<activity
android:name="MyBookActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.ALTERNATIVE" />
</intent-filter>
</activity>
where is your dot before MyBookActivity?
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