小编Ham*_*atu的帖子

我想得到一个孩子RelativeLayout.我使用代码得到这个:

aditionView.getAllChildren().

但现在子视图按照添加到该视图中的顺序出现.但我希望它们按照放置在视图中的位置递增顺序排列.

我想3½在android文本视图上显示.我尝试用unicode做但没有运气.请参阅下面的代码.谁能请帮忙.

additionalInfoString = additionalInfoString.replace("½",<sup><small>&frac12;</small></sup>);

您好我正在尝试为应用程序实现唤醒锁定.

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wl = pm.newWakeLock(PowerManager.FULL_WAKE_LOCK, "My Tag");

在定义PowerManager上面代码中显示的内容时似乎强制关闭.什么出错了？

我有一个(消息)列表,我想让用户能够从列表中删除这些项目.我已经扩展了一个ArrayAdapter并给它一个ArrayList我的消息,并且只想从该列表中删除一个项目,然后刷新ListView而不是重新加载整个已发送消息列表.问题是,如果只有一条消息并且我使用它删除它listAdapter.remove(messageObject),那么适配器仍然在调用getView()然后扔到NullPointerExceptions所有地方.我不确定最好的办法是什么.

Mainpage.java

public class Mainpage extends Activity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_mainpage);
        // Show the Up button in the action bar.
    //  setupActionBar();
    }

logcat的:

04-17 05:25:47.687: D/dalvikvm(1034): GC_FOR_ALLOC freed 68K, 5% free 2785K/2924K, paused 75ms, total 79ms
04-17 05:25:47.717: I/dalvikvm-heap(1034): Grow heap (frag case) to 3.473MB for 720016-byte allocation
04-17 05:25:47.797: D/dalvikvm(1034): GC_FOR_ALLOC freed 2K, 4% free 3485K/3628K, paused 76ms, total 76ms
04-17 05:25:48.057: D/AndroidRuntime(1034): Shutting down VM
04-17 05:25:48.057: W/dalvikvm(1034): threadid=1: thread exiting with uncaught …

你怎么能RadioButtonPreference在android中实现？就像CheckBoxPreference.

有没有解决方法？

我有两个Activity activity1和activity2,activity1有两个按钮,button1和button2.当点击button1它应链接到activity2应该在Action-bar中有标题有"am button1",当点击button2它再次链接到activity2并且它应该在Action-bar中有标题"am button2".

1. 当button1单击Activity1时,它应该通过put-extra of intent传递数据并更改活动action-bar title有"am button1".
2. Activity2应该从activity1接收数据并更改其中的action-bar.

任何身体请帮助我这样做.

这是java中典型的CLH-Lock：

public class CLHLock{  

    private final AtomicReference tail;

    // why we need this node?  
    private final ThreadLocal myPred;  

    private final ThreadLocal myNode;  

    public CLHLock() {  
        tail = new AtomicReference(new QNode());  
        myNode = new ThreadLocal() {  
            protected QNode initialValue() {  
                return new QNode();  
            }  
        };  

        myPred = new ThreadLocal();  
    }  

    public void lock() {  
        QNode node = myNode.get();  
        node.locked = true;  
        QNode pred = tail.getAndSet(node); 

        // this.myPred == pred 
        myPred.set(pred);  
        while (pred.locked) {  
        }  
    }  

    public void unlock() {  
        QNode node …

我正在阅读Android的教程,我有一个实现抽象类OnClickListener的类.问题是,在教程中它覆盖方法onClick时,这只有一个参数,但我的eclipse显示错误,因为onClick方法需要两个参数.

在我的错误代码下面的教程,我该如何修复它？

public class MainActivity extends Activity implements OnClickListener {
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    final Button button = (Button) findViewById(R.id.form_button);
    button.setOnClickListener((android.view.View.OnClickListener) this);
}

@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;
}

public void onClick(View v) {
    // TODO Auto-generated method stub
    switch (v.getId()) {
    case R.id.form_button:
        final EditText edit_name …

我正在尝试将字符串转换为日期:

Calendar calendar = Calendar.getInstance();
calendar.setTimeInMillis(System.currentTimeMillis());
Date dataEvento = null;

SimpleDateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
dataEvento = (Date)dateFormat.parse("28/08/2010"); //the app crash here

logcat的:

03-06 10:06:19.867: E/AndroidRuntime(426): FATAL EXCEPTION: main 
03-06 10:06:19.867: E/AndroidRuntime(426): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.ladessa.jccb/com.ladessa.jccb.MainActivity}: java.lang.ClassCastException: java.util.Date 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2663) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.app.ActivityThread.access$2300(ActivityThread.java:125) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.os.Handler.dispatchMessage(Handler.java:99) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at android.os.Looper.loop(Looper.java:123) 03-06 10:06:19.867: E/AndroidRuntime(426):   at android.app.ActivityThread.main(ActivityThread.java:4627) 
03-06 10:06:19.867: E/AndroidRuntime(426):  at java.lang.reflect.Method.invokeNative(Native …