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我正在开发的应用程序中采用无边框按钮的概念。到目前为止，借助以下问题，我可以完美地编辑我的按钮：

如何创建标准的无边框按钮（如提到的设计指南中）？

布局中的Android绘图分隔符/分隔线？

但是现在我需要显示不同的背景图像或在由于用户未填写某些必填字段而未启用按钮时强调的内容。

到目前为止我的代码：

some_activity.xml

<RelativeLayout
    android:id="@+id/layoutId"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentBottom="true" >

    <View
        android:layout_width="match_parent"
        android:layout_height="1dip"
        android:layout_marginLeft="4dip"
        android:layout_marginRight="4dip"
        android:background="@android:color/darker_gray"/>

    <Button
        android:id="@+id/buttonId"
        android:layout_width="match_parent"
        android:layout_height="70dp"
        android:background="?android:attr/selectableItemBackground"
        android:onClick="onButtonClicked"
        android:text="@string/someText"
        android:textColor="@color/someColor"
        android:textSize="25sp"
        android:textStyle="bold" />

</RelativeLayout>

现在，我打算在按钮的背景中放置一个条纹图像，以显示它何时被禁用。通过阅读下面的这个问题，我可以在它不是无边界的时候自定义我的按钮。

具有不同颜色的标准 Android 按钮

我尝试使用这个想法来自定义我的无边框按钮，如下面的代码：

drawable/borderless_button_bg.xml

<?xml version="1.0" encoding="utf-8"?>
<selector
    xmlns:android="http://schemas.android.com/apk/res/android">

    <item android:state_enabled="true" 
        android:drawable="?android:attr/selectableItemBackground" >
    </item>

    <item android:state_enabled="false"
        android:drawable="@drawable/stripes"
        android:tileMode="repeat" >
    </item>
</selector>

但这似乎是不可能的，一旦?android:attr/selectableItemBackground在borderless_button_bg.xml使程序崩溃。

LOGCAT

05-28 17:44:54.139: W/dalvikvm(31664): threadid=1: thread exiting with uncaught exception (group=0x40bc61f8)
05-28 17:44:54.154: E/AndroidRuntime(31664): FATAL EXCEPTION: main
05-28 17:44:54.154: E/AndroidRuntime(31664): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.Company.productname/com.Company.productname.myActivity}: android.view.InflateException: Binary XML file line #310: Error inflating class <unknown>
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1970)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1995)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread.access$600(ActivityThread.java:128)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1161)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.os.Handler.dispatchMessage(Handler.java:99)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.os.Looper.loop(Looper.java:137)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread.main(ActivityThread.java:4514)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at java.lang.reflect.Method.invokeNative(Native Method)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at java.lang.reflect.Method.invoke(Method.java:511)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at dalvik.system.NativeStart.main(Native Method)
05-28 17:44:54.154: E/AndroidRuntime(31664): Caused by: android.view.InflateException: Binary XML file line #310: Error inflating class <unknown>
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.createView(LayoutInflater.java:606)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at com.android.internal.policy.impl.PhoneLayoutInflater.onCreateView(PhoneLayoutInflater.java:56)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.onCreateView(LayoutInflater.java:653)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.createViewFromTag(LayoutInflater.java:678)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.rInflate(LayoutInflater.java:739)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.rInflate(LayoutInflater.java:742)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.inflate(LayoutInflater.java:489)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.inflate(LayoutInflater.java:396)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.inflate(LayoutInflater.java:352)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at com.android.internal.policy.impl.PhoneWindow.setContentView(PhoneWindow.java:273)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.Activity.setContentView(Activity.java:1835)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at com.Company.productname.myActivity.onCreate(TelaCaminhao.java:41)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.Activity.performCreate(Activity.java:4465)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1053)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1934)
05-28 17:44:54.154: E/AndroidRuntime(31664):    ... 11 more
05-28 17:44:54.154: E/AndroidRuntime(31664): Caused by: java.lang.reflect.InvocationTargetException
05-28 17:44:54.154: E/AndroidRuntime(31664):    at java.lang.reflect.Constructor.constructNative(Native Method)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at java.lang.reflect.Constructor.newInstance(Constructor.java:417)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.LayoutInflater.createView(LayoutInflater.java:586)
05-28 17:44:54.154: E/AndroidRuntime(31664):    ... 25 more
05-28 17:44:54.154: E/AndroidRuntime(31664): Caused by: android.content.res.Resources$NotFoundException: File res/drawable-ldpi/borderless_button_bg.xml from drawable resource ID #0x7f020000
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.content.res.Resources.loadDrawable(Resources.java:1958)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.content.res.TypedArray.getDrawable(TypedArray.java:601)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.view.View.<init>(View.java:2832)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.widget.TextView.<init>(TextView.java:558)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.widget.Button.<init>(Button.java:108)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.widget.Button.<init>(Button.java:104)
05-28 17:44:54.154: E/AndroidRuntime(31664):    ... 28 more
05-28 17:44:54.154: E/AndroidRuntime(31664): Caused by: org.xmlpull.v1.XmlPullParserException: Binary XML file line #7: <item> tag requires a 'drawable' attribute or child tag defining a drawable
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.graphics.drawable.StateListDrawable.inflate(StateListDrawable.java:178)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.graphics.drawable.Drawable.createFromXmlInner(Drawable.java:867)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.graphics.drawable.Drawable.createFromXml(Drawable.java:804)
05-28 17:44:54.154: E/AndroidRuntime(31664):    at android.content.res.Resources.loadDrawable(Resources.java:1955)
05-28 17:44:54.154: E/AndroidRuntime(31664):    ... 33 more

所以，我的问题是：我需要使用无边框按钮，并且当按钮被禁用时我需要明确。我有什么选择？

4

1 回答 1

0

这就是我设法解决我的问题的方法：

public class MyScreen extends Activity {
    private Button btnNext;
    private Drawable background;

    btnNext = (Button) this.findViewById(R.id.btnNext);
    background = btnNext.getBackground(); //stores the original Drawable characteristic

    ...

    //disable button
    if (!canGoNext) {
        btnNext.setEnabled(false);
        btnNext.setBackgroundResource(R.drawable.gray); //make it gray
    }
    //enable button
    else {
        btnNext.setEnabled(true);
        btnNext.setBackgroundDrawable(background); //make it selectableItemBackground again
    }
}
于 2013-08-16T19:56:53.903 回答