Question

您好这是我在Android上制作的第一个应用程序，我完成了我的应用程序没有任何问题，但突然我有这个错误，我不知道为什么它不工作，因为它之前工作正常。我不明白如何阅读原木猫所以请帮帮我！

07-24 12:00:15.170: D/AndroidRuntime(1866): Shutting down VM
07-24 12:00:15.170: W/dalvikvm(1866): threadid=1: thread exiting with uncaught exception (group=0xb1cefb20)
07-24 12:00:15.190: E/AndroidRuntime(1866): FATAL EXCEPTION: main
07-24 12:00:15.190: E/AndroidRuntime(1866): Process: com.sachinda.myfirstapp, PID: 1866
07-24 12:00:15.190: E/AndroidRuntime(1866): java.lang.NullPointerException
07-24 12:00:15.190: E/AndroidRuntime(1866):     at com.sachinda.myfirstapp.TwoPlayerActivity.onClick(TwoPlayerActivity.java:157)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.view.View.performClick(View.java:4438)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.view.View$PerformClick.run(View.java:18422)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.os.Handler.handleCallback(Handler.java:733)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.os.Handler.dispatchMessage(Handler.java:95)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.os.Looper.loop(Looper.java:136)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at android.app.ActivityThread.main(ActivityThread.java:5017)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at java.lang.reflect.Method.invokeNative(Native Method)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at java.lang.reflect.Method.invoke(Method.java:515)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
07-24 12:00:15.190: E/AndroidRuntime(1866):     at dalvik.system.NativeStart.main(Native Method)
07-24 12:00:21.151: I/Process(1866): Sending signal. PID: 1866 SIG: 9

编辑：这是我的代码，并在第157行的注释

@Override
public void onClick(View v) {

    switch (v.getId()) {
    case R.id.empty_button:

        if (one.isEnabled()) {
            oneChk = true;
            if (counter == 0) {
                v.setBackgroundResource(R.drawable.redsquarecircle);
                counter++;
                v.setTag(circle);
                if (v.getTag().equals(two.getTag())
                        && v.getTag().equals(three.getTag())) {
                    p1Wins.startAnimation(p1winner);
                    delayingDialog();
                } else if (v.getTag().equals(four.getTag())
                        && v.getTag().equals(seven.getTag())) {
                    p1Wins.startAnimation(p1winner);
                    delayingDialog();
                } else if (v.getTag().equals(five.getTag())
                        && v.getTag().equals(nine.getTag())) {
                    p1Wins.startAnimation(p1winner);
                    delayingDialog();
                } else {
                    if (!oneChk || !twoChk || !threeChk || !fourChk
                            || !fiveChk || !sixChk || !sevenChk
                            || !eightChk || !nineChk) {
                        //line 157
                        p2.startAnimation(p2turn);
                    } else {
                        draw.startAnimation(itsdraw);
                        delayingDialog();
                    }

                }

Answer 1

Log Cat文件有点难以理解，但请继续关注它，您将逐渐了解要查找的内容。

首先，错误类型通常应该非常明显：

显示java.lang.NullPointerException

这告诉你它已尝试引用一些变量或视图或其他任何内容并且它为空。

接下来，您需要滚动日志cat并查找引用您文件的行号。 com.sachinda ....是死的赠品：

com.sachinda.myfirstapp.TwoPlayerActivity.onClick（TwoPlayerActivity.java:157）

您可以双击此行，它应该会打开您的文件。无论如何看这条线，都有望解决这个问题。

查看您的编辑，p2和p2turn在哪里定义？您应该确保它们是成员变量，而不是在另一个方法中定义：

int mp2 = 42; //Member vairable, available to all methods in class 

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

    int p2 = 42; // private variable, only available to onCreate
}

致命错误不明白如何阅读日志cat错误

1 个答案: