Question

每当我尝试单击一个将文本输入到listView的按钮时，我的应用程序就崩溃了，我得到了＆＃34; java.lang.IllegalStateException：无法执行android的方法：onClick＆＃34 ;;我已经尝试过其他问题的解决方案，但我似乎无法找到自己的解决方案。任何帮助表示赞赏。

MainActivity.java

public class Intent_Constants {
public final static int INTENT_REQUEST_CODE=1;
public final static int INTENT_RESULT_CODE=1;
public final static int INTENT_REQUEST_CODE_2=2;
public final static int INTENT_RESULT_CODE_2=2;
public final static String INTENT_INFO_FIELD="info_field";
public final static String INTENT_INFO_DATA="info_data";
public final static String INTENT_ITEM_POSITION="item_position";
public final static String INTENT_CHANGED_INFO="changed_info";

Intent_Constants.java

public class EditMessageClass extends AppCompatActivity {
String infoText;
int position;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.add_promo_layout);
    Intent intent = getIntent();
    infoText = intent.getStringExtra(Intent_Constants.INTENT_INFO_DATA);
    position = intent.getIntExtra(Intent_Constants.INTENT_ITEM_POSITION,-1);
    EditText infoData = (EditText) findViewById(R.id.info);
    infoData.setText(infoText);
}

public void saveButtonClicked(View v){
    String changedinfoText = ((EditText)findViewById(R.id.info)).getText().toString();
    Intent intent = new Intent();
    intent.putExtra(Intent_Constants.INTENT_CHANGED_INFO,changedinfoText);
    intent.putExtra(Intent_Constants.INTENT_ITEM_POSITION, position);
    setResult(Intent_Constants.INTENT_RESULT_CODE_2,intent);
    finish();
}

EditMessageClass.java

public class EditFieldClass extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.add_promo_layout);
}

public void saveButtonClicked(View v){
    String infoText = ((EditText)findViewById(R.id.info)).getText().toString();
    if(infoText.equals("")){
    }
    else{
        Intent intent = new Intent();
        intent.putExtra(Intent_Constants.INTENT_INFO_FIELD,infoText);
        setResult(Intent_Constants.INTENT_RESULT_CODE,intent);
        finish();
    }
}

}

EditFieldClass.java

FATAL EXCEPTION: main
Process: gabriel.com.prototype, PID: 15435
java.lang.IllegalStateException: Could not execute method for android:onClick
    at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
    at android.view.View.performClick(View.java:5637)
    at android.view.View$PerformClick.run(View.java:22429)
    at android.os.Handler.handleCallback(Handler.java:751)
    at android.os.Handler.dispatchMessage(Handler.java:95)
    at android.os.Looper.loop(Looper.java:154)
    at android.app.ActivityThread.main(ActivityThread.java:6119)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)
Caused by: java.lang.reflect.InvocationTargetException
    at java.lang.reflect.Method.invoke(Native Method)
    at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
    at android.view.View.performClick(View.java:5637) 
    at android.view.View$PerformClick.run(View.java:22429) 
    at android.os.Handler.handleCallback(Handler.java:751) 
    at android.os.Handler.dispatchMessage(Handler.java:95) 
    at android.os.Looper.loop(Looper.java:154) 
    at android.app.ActivityThread.main(ActivityThread.java:6119) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776) 
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference
    at gabriel.com.prototype.EditFieldClass.saveButtonClicked(EditFieldClass.java:27)
    at java.lang.reflect.Method.invoke(Native Method) 
    at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
    at android.view.View.performClick(View.java:5637) 
    at android.view.View$PerformClick.run(View.java:22429) 
    at android.os.Handler.handleCallback(Handler.java:751) 
    at android.os.Handler.dispatchMessage(Handler.java:95) 
    at android.os.Looper.loop(Looper.java:154) 
    at android.app.ActivityThread.main(ActivityThread.java:6119) 
    at java.lang.reflect.Method.invoke(Native Method) 
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

}

日志

package(X)

Answer 1

根据你的logcat消息，我可以说你的EditText对象是<div style="position:relative"> <pre style="position:absolute"> hello </pre> <div style="position:absolute"> world </div> </div> 这个问题是由这条线引起的。

null

确保您在((EditText)findViewById(R.id.info)).getText().toString()中包含ID为'info'的EditText。

Answer 2

Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.text.Editable android.widget.EditText.getText()' on a null object reference
                                                                       at gabriel.com.prototype.EditFieldClass.saveButtonClicked(EditFieldClass.java:27)
                                                                       at java.lang.reflect.Method.invoke(Native Method) 
                                                                       at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
                                                                       at android.view.View.performClick(View.java:5637) 
                                                                       at android.view.View$PerformClick.run(View.java:22429) 
                                                                       at android.os.Handler.handleCallback(Handler.java:751) 
                                                                       at android.os.Handler.dispatchMessage(Handler.java:95) 
                                                                       at android.os.Looper.loop(Looper.java:154) 
                                                                       at android.app.ActivityThread.main(ActivityThread.java:6119) 
                                                                       at java.lang.reflect.Method.invoke(Native Method) 
                                                                       at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886) 
                                                                       at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

您的EditText为空，检查editText id 。

App Crashing - java.lang.IllegalStateException：无法执行android：onClick的方法

2 个答案: