我想從數據庫中檢索數據。它顯示爲display1.setOnClickListener(this);
錯誤請任何人提出一個解決方案給我。在android sqlite中檢索數據造成麻煩
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
display1=(Button)findViewById(R.id.button1);
inputid=(EditText)findViewById(R.id.display);
display1.setOnClickListener(this);
}
public void onClick(View v) {
// TODO Auto-generated method stub
int id=Integer.parseInt(inputid.getText().toString());
DBAdapter dbadapter=new DBAdapter(this);
Cursor c=dbadapter.display(id);
Toast.makeText(this, "Name: " + c.getString(1) , Toast.LENGTH_LONG).show();
}
logcat的是
12-26 16:27:26.438:d/AndroidRuntime(31283):關閉VM 12-26 16:27:26.438:W/dalvikvm(31283):線程ID = 1:線程退出未捕獲的異常(組= 0x40015560) 12-26 16:27:26.448:E/AndroidRuntime(31283):致命例外:主 12-26 16:27:26.448:E/AndroidRuntime(31283) :java.lang.RuntimeException:無法啓動活動ComponentInfo {com.android.database/com.android.database.Display}:java.lang.NullPointerException 12-26 16:27:26.448:E/AndroidRuntime(31283):在android.app.ActivityThread.performLaunchActi vity(ActivityThread.java:1647) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1663) 12-26 16:27:26.448: E/AndroidRuntime(31283):at android.app.ActivityThread.access $ 1500(ActivityThread.java:117) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.app.ActivityThread $ H.handleMessage (ActivityThread.java:931) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.os.Handler.dispatchMessage(Handler.java:99) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.os.Looper.loop(Looper.java:123) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.app.ActivityThread.main(ActivityThread.java :3683) 12-26 16:27:26.448:E/AndroidRuntime(31283):at java.lang.reflect.Method.invokeNative(Native Method) 12-26 16:27:26.448:E/AndroidRuntime(31283):at java.lang.reflect.Method.invoke(Method.java:507) 12-26 16:27:26.448:E/AndroidRuntime(31283) :at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:839) 12-26 16:27:26.448:E/AndroidRuntime(31283):at com.android.internal.os.ZygoteInit。 main(ZygoteInit.java:597) 12-26 16:27:26.448:E/AndroidRuntime(31283):at dalvik.system.NativeStart.main(Native Method) 12-26 16:27:26.448:E/AndroidRuntime (31283):導致:java.lang.NullPointerException 12-26 16:27:26.448:E/AndroidRuntime(31283):在com.android.database.Display.onCreate(Display.java:23)*** *錯誤 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.app.Instrumentation.callActi vityOnCreate(Instrumentation.java:1047) 12-26 16:27:26.448:E/AndroidRuntime(31283):at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1611) 12-26 16:27:26.448: E/AndroidRuntime(31283):... 11更多 12-26 16:27:28.448:I /進程(31283):發送信號。 PID:31283 SIG:9
粘貼錯誤日誌的完整代碼 – Pratik 2011-12-26 10:15:38
是的Pratik是正確的,在'display'方法中有什麼,我們如何建議你一個解決方案,而不知道完整的代碼與日誌? – 2011-12-26 10:19:34