Android：如何引用EditText视图

Question

I have the following layout:

<TextView 
    android:id = "@+id/HRNoninTextBox"
    android:layout_width="fill_parent" 
    android:layout_height="wrap_content"
    android:layout_below="@+id/exitbtn" 
    android:text="Heart Rate"
    android:textSize = "20sp"/>
<EditText 
    android:id="@+id/labelNoninHeartRate" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:text="00" 
    android:layout_alignParentRight="true">                         
</EditText>

from the code i refer to these views, form my activity, in this way:

TextView tvHr= (TextView)findViewById(R.id.HRNoninTextBox);

EditText etHr = (EditText)findViewById(R.id.labelNoninHeartRate);

the first one does not produce any error, while the second statement produce the following error:

 01-09 13:24:57.599: W/dalvikvm(28816): threadid=1: thread exiting with uncaught exception (group=0x4001e578)
01-09 13:24:57.619: E/AndroidRuntime(28816): FATAL EXCEPTION: main
01-09 13:24:57.619: E/AndroidRuntime(28816): java.lang.RuntimeException: Unable to start activity ComponentInfo{aid.assistant233/aid.assistant233.AidAssistant233Activity}: java.lang.ClassCastException: android.widget.TextView
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1651)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1667)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread.access$1500(ActivityThread.java:117)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:935)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.os.Handler.dispatchMessage(Handler.java:99)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.os.Looper.loop(Looper.java:130)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread.main(ActivityThread.java:3691)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at java.lang.reflect.Method.invokeNative(Native Method)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at java.lang.reflect.Method.invoke(Method.java:507)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:907)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:665)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at dalvik.system.NativeStart.main(Native Method)
01-09 13:24:57.619: E/AndroidRuntime(28816): Caused by: java.lang.ClassCastException: android.widget.TextView
01-09 13:24:57.619: E/AndroidRuntime(28816):    at aid.assistant233.AidAssistant233Activity.onCreate(AidAssistant233Activity.java:331)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
01-09 13:24:57.619: E/AndroidRuntime(28816):    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1615)
01-09 13:24:57.619: E/AndroidRuntime(28816):    ... 11 more

Where may be the problem?

Answer 1

Step1 : you can clean/build your project as everyone said . but If you are not getting your issue solve by clean/build then check my step2 for it.

Step:2: I am not Sure But Can you please check your xml file once again?

this also could be happen if You've two elements with the same ID:

<TextView android:text="Hello Ahmedabad:" 
    android:id="@+id/txtahmedabad" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content">
</TextView>

<EditText android:layout_height="wrap_content"
    android:layout_width="fill_parent" 
    android:id="@+id/txtahmedabad" 
    android:text="">
</EditText>

if this is so then Give them different IDs - it could picking the first one (the TextView ) which obviously can't be cast to an EditText .

Hope it will some how help you.