运行我的应用程序时收到以下错误：
02-09 18:01:19.582: D/AndroidRuntime(1306): Shutting down VM
02-09 18:01:19.582: W/dalvikvm(1306): threadid=1: thread exiting with uncaught exception (group=0xa4d86b20)
02-09 18:01:19.582: E/AndroidRuntime(1306): FATAL EXCEPTION: main
02-09 18:01:19.582: E/AndroidRuntime(1306): Process: com.shashank.sharjahinternationalairport, PID: 1306
02-09 18:01:19.582: E/AndroidRuntime(1306): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.shashank.sharjahinternationalairport/com.shashank.sharjahinternationalairport.MainActivity}: java.lang.ClassCastException: android.widget.ImageButton cannot be cast to android.widget.Button
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread.access$800(ActivityThread.java:135)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.os.Handler.dispatchMessage(Handler.java:102)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.os.Looper.loop(Looper.java:136)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread.main(ActivityThread.java:5017)
02-09 18:01:19.582: E/AndroidRuntime(1306): at java.lang.reflect.Method.invokeNative(Native Method)
02-09 18:01:19.582: E/AndroidRuntime(1306): at java.lang.reflect.Method.invoke(Method.java:515)
02-09 18:01:19.582: E/AndroidRuntime(1306): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
02-09 18:01:19.582: E/AndroidRuntime(1306): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
02-09 18:01:19.582: E/AndroidRuntime(1306): at dalvik.system.NativeStart.main(Native Method)
02-09 18:01:19.582: E/AndroidRuntime(1306): Caused by: java.lang.ClassCastException: android.widget.ImageButton cannot be cast to android.widget.Button
02-09 18:01:19.582: E/AndroidRuntime(1306): at com.shashank.sharjahinternationalairport.MainActivity.onCreate(MainActivity.java:23)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.Activity.performCreate(Activity.java:5231)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
02-09 18:01:19.582: E/AndroidRuntime(1306): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
02-09 18:01:19.582: E/AndroidRuntime(1306): ... 11 more
我不确定为什么会出现这种错误？任何见解？感谢。
这是main.xml代码：
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<ImageButton
android:id="@+id/visitorInfo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignTop="@+id/saaDca"
android:layout_marginTop="48dp"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/flightInfo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/visitorInfo"
android:layout_alignTop="@+id/cargo"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/cargo"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:layout_marginRight="24dp"
android:layout_marginTop="46dp"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/saaDca"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/flightInfo"
android:layout_marginLeft="20dp"
android:layout_marginTop="37dp"
android:layout_toRightOf="@+id/visitorInfo"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/airportGuide"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/cargo"
android:layout_below="@+id/saaDca"
android:src="@drawable/ic_launcher" />
这是airport_guide.xml代码：
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageButton
android:id="@+id/aboutAirport"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/transferAndTransit"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/arrivals"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/fs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/departure"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
<ImageButton
android:id="@+id/virtualTours"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:src="@drawable/ic_launcher" />
</LinearLayout>
这是java代码：
package com.shashank.sharjahinternationalairport;
import android.app.Activity;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
public class MainActivity extends Activity {
Button flightInfoButton;
Button airportGuideButton;
Button visitorInfoButton;
Button saaDcaButton;
Button cargoButton;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
flightInfoButton = (Button) findViewById(R.id.flightInfo);
airportGuideButton = (Button) findViewById(R.id.airportGuide);
visitorInfoButton = (Button) findViewById(R.id.visitorInfo);
saaDcaButton = (Button) findViewById(R.id.saaDca);
cargoButton = (Button) findViewById(R.id.cargo);
airportGuideButton.setOnClickListener(new OnClickListener(){
@Override
public void onClick(View V){
setContentView(R.layout.airport_guide);
}
});
}
@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;
}
}
答案 0 :(得分：1)
您只需要替换此
Button myButton = (Button)findViewById(R.id.my_image_button);
使用
ImageButton myImageButton = (ImageButton) findViewById(R.id.my_image_Button);
答案 1 :(得分：0)
查看您的MainActivity第23行
Caused by: java.lang.ClassCastException: android.widget.ImageButton cannot be cast to android.widget.Button
这是你的错误，没有代码，我们无法分清究竟是什么错。 IT可能与ImageButton不是Button
看一下参考文献：
http://developer.android.com/reference/android/widget/ImageButton.html
答案 2 :(得分：0)
你可能有一句话说明：
Button myButton = (Button)findViewById(R.id.my_image_button);
在xml中，id为“my_image_button”的元素（为示例选择的名称）是ImageButton。不幸的是，你不能使用和ImageButton作为标准Button。
然后您应该通过以下方式替换该行：
ImageButton myImageButton = (ImageButton) findViewById(R.id.my_image_Button);