Question

这应该是一种多对话框，可以询问您的问题并保存您的答案，出于某种原因，我的代码在监听器上崩溃了

final Context context = this;
 int currentshape, goalshape; // 0 = lean , 1 = fat , 2 = skinny fat || 0 = shredded , 1 = powerlifter, 2 = bodybuiler.
double weight;
double height;
boolean dialogflag=false; // true if dialog finsihed then turned to false
Button[] current, goals; // buttons
EditText mainheight,mainweight; // question3 weight + height

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.splash_load);
    mainheight = (EditText) findViewById(R.id.height);
    mainweight = (EditText) findViewById(R.id.weight);
    current = new Button[3];
    goals = new Button[3];

    // dialog pop
    final Dialog dialog = new Dialog(context);
    dialog.setContentView(R.layout.question1);
    dialog.show();
    //
    current[0] = (Button) findViewById(R.id.btnLean);
    current[1] = (Button) findViewById(R.id.btnFat);
    current[2] = (Button) findViewById(R.id.btnSkinnyFat);
    for (int i = 0; i < 3; i++)
        current[i].setOnClickListener(this);
    // dialog main code
    if(dialogflag==true){ // second dialog (goal dialog)
        dialog.dismiss();
        dialog.setContentView(R.layout.question2);
        dialog.show();
        // setup buttons
        goals[0] = (Button) findViewById(R.id.btnShrededd);
        goals[1] = (Button) findViewById(R.id.btnPowerLifting);
        goals[2] = (Button) findViewById(R.id.btnBodyBuilding);
        for (int i = 0; i < 3; i++)
            goals[i].setOnClickListener(this);
        // wait for next button
        dialogflag=false;
        if(dialogflag==true){ // third dialog (height + weight dialog)
            dialog.dismiss();
            dialogflag=false;
            Intent intent = new Intent(this,MainActivity.class); // transfering to main activity.
            startActivity(intent);
            finish();
        }
    }
}

@Override
public void onClick(View v) {
    // dialog buttons.
    switch (v.getId()) {
        case R.id.btnLean:
            currentshape = 0;
            dialogflag = true;
            break;
        case R.id.btnFat:
            currentshape = 1;
            dialogflag = true;
            break;
        case R.id.btnSkinnyFat:
            currentshape = 2;
            dialogflag = true;
            break;
        case R.id.btnShrededd:
            goalshape=0;
            dialogflag=true;
            break;
        case R.id.btnPowerLifting:
            goalshape=1;
            dialogflag=true;
            break;
        case R.id.btnBodyBuilding:
            goalshape=2;
            dialogflag=true;
            break;
        case R.id.btnOK:
            weight=Double.valueOf(mainweight.getText().toString());
            height=Double.valueOf(mainweight.getText().toString());
            dialogflag=true;
            break;
    }

这是错误日志

              Process: com.example.gold.mnfitness, PID: 4322
              java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.gold.mnfitness/com.example.gold.mnfitness.First_login}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2902)
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3037)
                  at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78)
                  at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108)
                  at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68)
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1797)
                  at android.os.Handler.dispatchMessage(Handler.java:106)
                  at android.os.Looper.loop(Looper.java:193)
                  at android.app.ActivityThread.main(ActivityThread.java:6642)
                  at java.lang.reflect.Method.invoke(Native Method)
                  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493)
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)
               Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.widget.Button.setOnClickListener(android.view.View$OnClickListener)' on a null object reference
                  at com.example.gold.mnfitness.First_login.onCreate(First_login.java:44)
                  at android.app.Activity.performCreate(Activity.java:7131)
                  at android.app.Activity.performCreate(Activity.java:7122)
                  at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1271)
                  at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2882)
                  at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3037) 
                  at android.app.servertransaction.LaunchActivityItem.execute(LaunchActivityItem.java:78) 
                  at android.app.servertransaction.TransactionExecutor.executeCallbacks(TransactionExecutor.java:108) 
                  at android.app.servertransaction.TransactionExecutor.execute(TransactionExecutor.java:68) 
                  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1797) 
                  at android.os.Handler.dispatchMessage(Handler.java:106) 
                  at android.os.Looper.loop(Looper.java:193) 
                  at android.app.ActivityThread.main(ActivityThread.java:6642) 
                  at java.lang.reflect.Method.invoke(Native Method) 
                  at com.android.internal.os.RuntimeInit$MethodAndArgsCaller.run(RuntimeInit.java:493) 
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:858)

应该显示多个对话框的代码，每个对话框具有不同的xml。但由于某种原因，它无法在按钮arr中放置按钮的ID。如果有人可以告诉我我应该如何编码，这是我在这里的第一篇文章，对不起，如果我没有正确地张贴它。

Answer 1

您的日志显示您的按钮：

current[0]
current[1]
current[2]
goals[0] 
goals[1]
goals[2]

为空，请检查您的xml。 R.layout.splash_load是您正确的布局吗？

如何修复多对话框Android Studio

1 个答案: