Question

我正在构建一个应用程序，并尝试使用切换开关来更改单独类中某些setter的值（请参阅下面的 r.setStart（））。我有几个问题。第一个是应用程序崩溃完全代码到位。第二个是当我在应用程序中保留设置活动时，开关会自动切换到关闭状态。

设置活动中的开关：

public int tierChoice() {
        Switch commSwitch = (Switch) findViewById(R.id.commSwitch);
        Switch enchSwitch = (Switch) findViewById(R.id.enchSwitch);
        Switch rareSwitch = (Switch) findViewById(R.id.rareSwitch);
        Switch epicSwitch = (Switch) findViewById(R.id.epicSwitch);
        Switch legeSwitch = (Switch) findViewById(R.id.legeSwitch);

        Boolean commSwitchState = commSwitch.isChecked();
        Boolean enchSwitchState = enchSwitch.isChecked();
        Boolean rareSwitchState = rareSwitch.isChecked();
        Boolean epicSwitchState = epicSwitch.isChecked();
        Boolean legeSwitchState = legeSwitch.isChecked();

        if (commSwitchState) {
            return 1;
        }
        if (enchSwitchState) {
            return 2;
        }
        if (rareSwitchState) {
            return 3;
        }
        if (epicSwitchState) {
            return 4;
        }
        if (legeSwitchState) {
            return 5;
        } return 0;
    }

在主要活动中，我希望交换机的状态返回并更新setter值：

public void level(View v) {
    SettingsActivity settings = new SettingsActivity();
    int tierChoice = settings.tierChoice();

    //Roll
    Roll r = new Roll();

    //Tier Choice
    if (tierChoice == 1) {
        r.setStart(1);
        r.setEnd(50);
    } else if (tierChoice == 2) {
        r.setStart(51);
        r.setEnd(80);
    } else if (tierChoice == 3) {
        r.setStart(81);
        r.setEnd(90);
    } else if (tierChoice == 4) {
        r.setStart(91);
        r.setEnd(96);
    } else if (tierChoice == 5) {
        r.setStart(96);
        r.setEnd(100);
    } else {
        r.setStart(1);
        r.setEnd(100);
    }
}

第二段代码实际上完全崩溃了应用程序。谢谢你的帮助！

编辑以提供堆栈跟踪：

05-23 15:35:45.703 880-880/net.zingrook.mobiloot E/AndroidRuntime: FATAL EXCEPTION: main
Process: net.zingrook.mobiloot, PID: 880
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
at android.view.View.performClick(View.java:5226)
at android.view.View$PerformClick.run(View.java:21266)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:168)
at android.app.ActivityThread.main(ActivityThread.java:5781)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:5226) 
at android.view.View$PerformClick.run(View.java:21266) 
at android.os.Handler.handleCallback(Handler.java:739) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:168) 
at android.app.ActivityThread.main(ActivityThread.java:5781) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687) 
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'android.view.Window$Callback android.view.Window.getCallback()' on a null object reference
at android.support.v7.app.AppCompatDelegateImplBase.<init>(AppCompatDelegateImplBase.java:120)
at android.support.v7.app.AppCompatDelegateImplV9.<init>(AppCompatDelegateImplV9.java:155)
at android.support.v7.app.AppCompatDelegateImplV11.<init>(AppCompatDelegateImplV11.java:31)
at android.support.v7.app.AppCompatDelegateImplV14.<init>(AppCompatDelegateImplV14.java:55)
at android.support.v7.app.AppCompatDelegateImplV23.<init>(AppCompatDelegateImplV23.java:33)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:203)
at android.support.v7.app.AppCompatDelegate.create(AppCompatDelegate.java:185)
at android.support.v7.app.AppCompatActivity.getDelegate(AppCompatActivity.java:519)
at android.support.v7.app.AppCompatActivity.findViewById(AppCompatActivity.java:190)
at net.zingrook.mobiloot.HomeScreenActivity.tierChoice(HomeScreenActivity.java:47)
at net.zingrook.mobiloot.LootChest.level(LootChest.java:26)
at java.lang.reflect.Method.invoke(Native Method) 
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288) 
at android.view.View.performClick(View.java:5226) 
at android.view.View$PerformClick.run(View.java:21266) 
at android.os.Handler.handleCallback(Handler.java:739) 
at android.os.Handler.dispatchMessage(Handler.java:95) 
at android.os.Looper.loop(Looper.java:168) 
at android.app.ActivityThread.main(ActivityThread.java:5781) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:797) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:687)

承载失败的onCreate：

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_loot_chest);
//        final MediaPlayer legendMP = MediaPlayer.create(this, R.raw.legend);
//        legendMP.start();
    }

    public void level(View v) {
        HomeScreenActivity home = new HomeScreenActivity();
        int tierChoice = home.tierChoice(); //one null exception here

另一个：

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

public void lootChest(View view) {
    Intent intent = new Intent(this, LootChest.class);
    startActivity(intent);
}

public int tierChoice() {
    Switch commSwitch = (Switch) findViewById(R.id.commSwitch); //exception here

切换切换到更改设置器值

0 个答案: