在自定義適配器中更改ListView中形狀的背景色

Question

我有一個ListView，它有一些人和他們獨特的顏色，我用xml創建了一個矩形，然後把它作爲ImageView的背景。當我嘗試改變它的顏色時，它會崩潰。

這裏是我的自定義適配器的getView（）方法：

vi = inflater.inflate(R.layout.sonuclisterow, null); 
    ImageView adayRenk = (ImageView)vi.findViewById(R.id.adayRenk); 
    GradientDrawable sd = (GradientDrawable) adayRenk.getBackground(); 
    sd.setColor(Color.BLACK); //Color.BLACK is just for trying to change, there will be variable later 

形狀：

<?xml version="1.0" encoding="UTF-8"?> 
<shape xmlns:android="http://schemas.android.com/apk/res/android" 
    android:shape="rectangle"> 
    <solid android:color="#F0F0F0" /> 
</shape> 

的logcat：

01-05 19:11:32.545: D/dalvikvm(30161): GC_FOR_ALLOC freed 5735K, 23% free 20374K/26183K, paused 18ms, total 18ms 
01-05 19:11:32.665: D/AndroidRuntime(30161): Shutting down VM 
01-05 19:11:32.665: W/dalvikvm(30161): threadid=1: thread exiting with uncaught exception (group=0x40f24300) 
01-05 19:11:32.675: E/AndroidRuntime(30161): FATAL EXCEPTION: main 
01-05 19:11:32.675: E/AndroidRuntime(30161): java.lang.NullPointerException 
01-05 19:11:32.675: E/AndroidRuntime(30161): at com.paperless.custom.LazyAdapter2.getView(LazyAdapter2.java:63) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.AbsListView.obtainView(AbsListView.java:2267) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.ListView.measureHeightOfChildren(ListView.java:1244) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.ListView.onMeasure(ListView.java:1156) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.RelativeLayout.measureChild(RelativeLayout.java:602) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:415) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.LinearLayout.measureChildBeforeLayout(LinearLayout.java:1390) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.LinearLayout.measureHorizontal(LinearLayout.java:1038) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.LinearLayout.onMeasure(LinearLayout.java:576) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.LinearLayout.measureVertical(LinearLayout.java:833) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.LinearLayout.onMeasure(LinearLayout.java:574) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4814) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.widget.FrameLayout.onMeasure(FrameLayout.java:310) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2148) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.View.measure(View.java:15172) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewRootImpl.performMeasure(ViewRootImpl.java:1848) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewRootImpl.measureHierarchy(ViewRootImpl.java:1100) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1273) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:998) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4212) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:736) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.Choreographer.doCallbacks(Choreographer.java:566) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.Choreographer.doFrame(Choreographer.java:536) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:722) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.os.Handler.handleCallback(Handler.java:615) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.os.Handler.dispatchMessage(Handler.java:92) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.os.Looper.loop(Looper.java:137) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at android.app.ActivityThread.main(ActivityThread.java:4745) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at java.lang.reflect.Method.invokeNative(Native Method) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at java.lang.reflect.Method.invoke(Method.java:511) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553) 
01-05 19:11:32.675: E/AndroidRuntime(30161): at dalvik.system.NativeStart.main(Native Method) 

63號線在LazyAdapter2是sd.setColor(Color.BLACK);

Answer 1

背景必須使用ImageView的android:background屬性進行設置。