android - 调用我的动画时我的应用程序崩溃了？

Question

我有一个 AnimationDrawable 对象，当我调用 wavingAndroid 方法时，游戏崩溃了。有什么帮助吗？这是我的 MainActivity.java

    private void wavingAndroid(){
ImageView animateAndroid = (ImageView) findViewById(R.id.dancingAndroidLogo);
animateAndroid.setImageResource(R.drawable.movingandroid);
AnimationDrawable androidAnimation = (AnimationDrawable) animateAndroid.getDrawable();
androidAnimation.start();
    }

我想在这里调用它:

    public void onClick(View v){
    wavingAndroid();
    }

这是我的 xml 文件:

    <animation-list xmlns:android="http://schemas.android.com/apk/res/android"
android:oneshot="true" >

<item
    android:drawable="@drawable/dancinglogo01"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo02"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo03"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo04"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo05"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo06"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo07"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo08"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo09"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo10"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo11"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo12"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo13"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo14"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo15"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo16"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo17"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo18"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo19"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo20"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo21"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo22"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo23"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo24"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo25"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo27"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo28"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo29"
    android:duration="41"/>
<item
    android:drawable="@drawable/dancinglogo30"
    android:duration="41"/>

<!-- Reset to original -->
<item
    android:drawable="@drawable/dancinglogo01"
    android:duration="10"/>

    </animation-list>

这是我的日志:

    08-17 09:59:22.487: E/AndroidRuntime(22392): FATAL EXCEPTION: main
    08-17 09:59:22.487: E/AndroidRuntime(22392): java.lang.NullPointerException
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at         com.thatnerdstuff.build_a_rig.MainActivity.wavingAndroid(MainActivity.java:149)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at com.thatnerdstuff.build_a_rig.MainActivity.access$0(MainActivity.java:145)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at com.thatnerdstuff.build_a_rig.MainActivity$1.onClick(MainActivity.java:46)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.view.View.performClick(View.java:4203)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.view.View$PerformClick.run(View.java:17189)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.os.Handler.handleCallback(Handler.java:615)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.os.Handler.dispatchMessage(Handler.java:92)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.os.Looper.loop(Looper.java:137)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at android.app.ActivityThread.main(ActivityThread.java:4950)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at java.lang.reflect.Method.invokeNative(Native Method)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at java.lang.reflect.Method.invoke(Method.java:511)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1004)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:771)
    08-17 09:59:22.487: E/AndroidRuntime(22392):    at dalvik.system.NativeStart.main(Native Method)

在这个问题上的任何帮助都会很棒，因为我已经查看了许多其他论坛，并试图找到修复程序，但我不知道它来自哪里。我试过清理项目但什么也没有。提前致谢!

Answer 1

尝试在代码中将图像加载到 AnimationDrawable，如下所示:

AnimationDrawable frameAnimation= new AnimationDrawable();
frameAnimation.addFrame(getResources().getDrawable(R.drawable.dancinglogo01), 41);
frameAnimation.addFrame(getResources().getDrawable(R.drawable.dancinglogo02), 41);

在您的wavingAndroid() 方法中添加所有这样的帧，然后像这样将其加载到imageView

animateAndroid = (ImageView) findViewById(R.id.dancingAndroidLogo);
animaateAndroid.setBackgroundDrawable(frameAnimation);

现在在您的 onClick() 方法中使用以下方法启动动画:

frameAnimation.start();