Android 检查意图中的动作并做一些逻辑

Question

我将两个 Intent 过滤器合二为一 activity。 `

        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <intent-filter>
            <action android:name="android.intent.action.VIEW" />
            <data  android:scheme="https://dou.ua/lenta/" />
            <category android:name="android.intent.category.DEFAULT" />
        </intent-filter> `

并检查尝试检查创建 activity 时的操作。

 protected void onCreate(@Nullable Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main_layout);
    ButterKnife.bind(this);
    mToolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(mToolbar);

    Intent intent = getIntent();
    String action = intent.getAction();
    if (action.equals("android.intent.action.VIEW ")) {

    } else {
      getSupportFragmentManager().addOnBackStackChangedListener(this);
      isDisplayingHomeBtn();
      getSupportFragmentManager().beginTransaction()
          .replace(R.id.container, new FeedFragment())
          .commit();
    }
  }

但是我有一个 NullPointerException

Process: com.bogdan_kolomiets_1996.bogdan.dou_feed, PID: 5237 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.bogdan_kolomiets_1996.bogdan.dou_feed/com.bogdan_kolomiets_1996.bogdan.dou_feed.ui.MainActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.Object android.os.Bundle.get(java.lang.String)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2622) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2692) at android.app.ActivityThread.access0(ActivityThread.java:179) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1540) at android.os.Handler.dispatchMessage(Handler.java:111) at android.os.Looper.loop(Looper.java:194) at android.app.ActivityThread.main(ActivityThread.java:5795) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1005) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:800) at de.robv.android.xposed.XposedBridge.main(XposedBridge.java:114) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.Object android.os.Bundle.get(java.lang.String)' on a null object reference at com.bogdan_kolomiets_1996.bogdan.dou_feed.ui.MainActivity.onCreate(MainActivity.java:38) at android.app.Activity.performCreate(Activity.java:6071) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1123) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2575) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2692) at android.app.ActivityThread.access0(ActivityThread.java:179) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1540) at android.os.Handler.dispatchMessage(Handler.java:111) at android.os.Looper.loop(Looper.java:194) at android.app.ActivityThread.main(ActivityThread.java:5795) at java.lang.reflect.Method.invoke(Native Method) at java.lang.reflect.Method.invoke(Method.java:372)

Answer 1

你确定你的 activity 放在这里 'com.bogdan_kolomiets_1996.bogdan.dou_feed/com.bogdan_kolomiets_1996.bogdan.dou_feed.ui.MainActivity' 吗？

此错误发生在您尝试启动 activity 时，而不是您尝试执行某个操作时。

Android 检查意图中的动作并做一些逻辑

Android check action in intent and do some logic

android

android-activity

nullpointerexception

intentfilter