09-08 01:52:58.997: E/AndroidRuntime(737): Uncaught handler: thread main exiting due to uncaught exception
09-08 01:52:59.007: E/AndroidRuntime(737): java.lang.NullPointerException
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View.showContextMenu(View.java:2380)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View.performLongClick(View.java:2366)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.widget.TextView.performLongClick(TextView.java:7230)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View$CheckForLongPress.run(View.java:8312)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Handler.handleCallback(Handler.java:587)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Handler.dispatchMessage(Handler.java:92)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Looper.loop(Looper.java:123)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.app.ActivityThread.main(ActivityThread.java:4203)
09-08 01:52:59.007: E/AndroidRuntime(737): at java.lang.reflect.Method.invokeNative(Native Method)
09-08 01:52:59.007: E/AndroidRuntime(737): at java.lang.reflect.Method.invoke(Method.java:521)
09-08 01:52:59.007: E/AndroidRuntime(737): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
09-08 01:52:59.007: E/AndroidRuntime(737): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
09-08 01:52:59.007: E/AndroidRuntime(737): at dalvik.system.NativeStart.main(Native Method)上面的错误信息来自:我本想要实现,长按一个按钮,该按钮被删除,但是不知道为何老是报上述错误。代码:
public class RedirectActivity extends Activity {
Button button = null;
Button button1 = null;
LinearLayout linearLayout = null;
Bundle saved = null;
boolean flag;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
this.saved = savedInstanceState;
button1 = (Button)findViewById(R.id.button1);
linearLayout = (LinearLayout)findViewById(R.id.layout);
button = new Button(this);
button.setId(R.id.button2+1);
button.setText("add one button");
button.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
// linearLayout.addView(button);
linearLayout.addView(button, 1);
button1.setOnLongClickListener(new View.OnLongClickListener() {
public boolean onLongClick(View v) {
// ok();
linearLayout.removeView(button1);
return false;
}
});
}
}
09-08 01:52:59.007: E/AndroidRuntime(737): java.lang.NullPointerException
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View.showContextMenu(View.java:2380)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View.performLongClick(View.java:2366)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.widget.TextView.performLongClick(TextView.java:7230)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.view.View$CheckForLongPress.run(View.java:8312)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Handler.handleCallback(Handler.java:587)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Handler.dispatchMessage(Handler.java:92)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.os.Looper.loop(Looper.java:123)
09-08 01:52:59.007: E/AndroidRuntime(737): at android.app.ActivityThread.main(ActivityThread.java:4203)
09-08 01:52:59.007: E/AndroidRuntime(737): at java.lang.reflect.Method.invokeNative(Native Method)
09-08 01:52:59.007: E/AndroidRuntime(737): at java.lang.reflect.Method.invoke(Method.java:521)
09-08 01:52:59.007: E/AndroidRuntime(737): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:791)
09-08 01:52:59.007: E/AndroidRuntime(737): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:549)
09-08 01:52:59.007: E/AndroidRuntime(737): at dalvik.system.NativeStart.main(Native Method)上面的错误信息来自:我本想要实现,长按一个按钮,该按钮被删除,但是不知道为何老是报上述错误。代码:
public class RedirectActivity extends Activity {
Button button = null;
Button button1 = null;
LinearLayout linearLayout = null;
Bundle saved = null;
boolean flag;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
this.saved = savedInstanceState;
button1 = (Button)findViewById(R.id.button1);
linearLayout = (LinearLayout)findViewById(R.id.layout);
button = new Button(this);
button.setId(R.id.button2+1);
button.setText("add one button");
button.setLayoutParams(new LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
// linearLayout.addView(button);
linearLayout.addView(button, 1);
button1.setOnLongClickListener(new View.OnLongClickListener() {
public boolean onLongClick(View v) {
// ok();
linearLayout.removeView(button1);
return false;
}
});
}
}
true和flase表示事件是否被消耗,
http://blog.csdn.net/ddna/article/details/5451722 看看这篇文章