相关疑难解决方法(0)

我想点击一个按钮播放声音文件.声音只有1秒长.我点击按钮的前几次播放效果很好,但过了一会儿它会给出一个NullPointerException.这是代码:

button[i].setOnClickListener(new OnClickListener() {
    public void onClick(View view) {        
        mp = MediaPlayer.create(Test.this, R.raw.mysound);   
        mp.start();
    }
});

这是例外:

07-29 23:07:27.690: ERROR/AndroidRuntime(10542): Uncaught handler: thread main exiting due to uncaught exception
07-29 23:07:27.710: ERROR/AndroidRuntime(10542): java.lang.NullPointerException
07-29 23:07:27.710: ERROR/AndroidRuntime(10542):     at com.example.mypackage.Test$3.onClick(Test.java:270)

我正在开发一个视频应用程序.完成第一个视频播放后,在"OnCopletion"中我试图开始一个新的视频.但它只是停止(不是崩溃)而什么也不做.在日志中:

10-19 09:44:49.056: ERROR/MediaPlayer(4654): setDataSource called in state 128
10-19 09:44:49.056: WARN/System.err(4654): java.lang.IllegalStateException
10-19 09:44:49.056: WARN/System.err(4654):     at android.media.MediaPlayer.setDataSource(Native Method)
10-19 09:44:49.056: WARN/System.err(4654):     at ru.osiris.BusAdvertising.BusAdvertisingActivity.onCompletion(BusAdvertisingActivity.java:1255)
10-19 09:44:49.056: WARN/System.err(4654):     at android.media.MediaPlayer$EventHandler.handleMessage(MediaPlayer.java:1304)
10-19 09:44:49.056: WARN/System.err(4654):     at android.os.Handler.dispatchMessage(Handler.java:99)
10-19 09:44:49.056: WARN/System.err(4654):     at android.os.Looper.loop(Looper.java:123)
10-19 09:44:49.056: WARN/System.err(4654):     at android.app.ActivityThread.main(ActivityThread.java:4627)
10-19 09:44:49.056: WARN/System.err(4654):     at java.lang.reflect.Method.invokeNative(Native Method)
10-19 09:44:49.056: WARN/System.err(4654):     at java.lang.reflect.Method.invoke(Method.java:521)
10-19 09:44:49.056: WARN/System.err(4654):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
10-19 09:44:49.056: WARN/System.err(4654):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
10-19 09:44:49.056: WARN/System.err(4654):     at dalvik.system.NativeStart.main(Native Method)

这是什么意思？我该如何解决？有我的代码:

public class BusAdvertisingActivity extends Activity implements LocationListener, OnBufferingUpdateListener, …

嗨,大家好,我想在点击文字时播放某个mp3文件.例如,我点击了"Nicholas"这个词,应用程序必须播放nicholas.mp3 ...

对不起我的乱码,我是android dev的新手:

package com.example.playword;

import java.io.IOException;

import android.app.Activity;
import android.media.MediaPlayer;
import android.os.Bundle;
//import android.os.Handler;
import android.view.View;
//import android.view.View.OnClickListener;
//import android.widget.Button;
import android.widget.TextView;

public class PlayWord extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);

        //final Handler mHandler = new Handler();

        final TextView nicholas = (TextView) findViewById(R.id.nicholas);
        final TextView was = (TextView) findViewById(R.id.was);

        nicholas.setText("Nicholas ");
        was.setText("was ");        

        /*
        Button btn = (Button) (findViewById(R.id.nicholasBtn));

        btn.setOnClickListener(new OnClickListener(){
            @Override
            public void …

嗨,任何人都可以帮助我完成我的小项目,我一直在关注这个教程,我得到了我在EditText中插入1分钟的部分,进度条工作正常1每秒进度但是当我输入超过1分钟时EditText进度条不起作用.它没有下降请帮忙吗？

main.xml中

 <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" 
android:background="#086A87">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:orientation="horizontal"
    android:padding="10dp" >

    <EditText
        android:id="@+id/edtTimerValue"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_weight="1"
        android:ems="10"
        android:hint="minutes"
        android:inputType="phone" />

    <Button
        android:id="@+id/btnStartTime"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:layout_weight="2"
        android:gravity="center"
        android:text="Start Timer" 
        android:background="@drawable/custombuttongreen"
        android:textColor="#fff"/>

    <Button
        android:id="@+id/btnStopTime"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_margin="5dp"
        android:layout_weight="2"
        android:gravity="center"
        android:text="Stop Timer"
        android:visibility="gone" 
        android:background="@drawable/custombuttongreen"
        android:textColor="#fff"/>

</LinearLayout>

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:orientation="vertical" >

</LinearLayout>



<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"  >

    <ProgressBar
    android:id="@+id/progressbar"
    android:layout_width="350dip"
    android:layout_height="350dip"
    android:indeterminate="false"
    android:progressDrawable="@drawable/circle"
    android:background="@drawable/circle_shape"
    style="?android:attr/progressBarStyleHorizontal"
    android:max="60"
    android:progress="0" />

    <TextView
    android:id="@+id/tvTimeCount"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_centerHorizontal="true"
    android:layout_centerVertical="true"
    android:text="00:00" 
    android:textColor="#fff" …