为什么我会收到默认的 Activity not found 错误？

Question

I have used intent-filter here:

<intent-filter>
    <action android:name="android.intent.action.MAIN"/>
    <action android:name="com.example.test.testActivity"/>
    <category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>

I invalidated and restarted several times, but it failed.

I used Micer´s method to do things like this

android {
    ....
    ....

    sourceSets {
        main.java.srcDirs += 'src/main/<YOUR DIRECTORY>'
    }
}

But it still has the error Default Activity not found

android {
    compileSdkVersion 24
    buildToolsVersion "25.0.2"
    defaultConfig {
        applicationId "com.example.test"
        minSdkVersion 15
        targetSdkVersion 24
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
    }
}



<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.example.test">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">
        <activity android:name=".testActivity"></activity>/>

        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <action android:name="com.example.test.testActivity"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>


    </application>

</manifest>

and I think this maybe the source:

 <activity android:name=".testActivity"></activity>/>

error:Reports empty tag body. The validation works in XML / JSP / JSPX / HTML/ XHTML file types.

How can I solve this issue?

Answer 1

The intent-filter goes INSIDE your activity TAG to make it the default like so:

    <activity android:name=".testActivity">
          <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>  
    </activity>

    </application>
</manifest>

Answer 2

Replace this,

<activity android:name=".testActivity"></activity>/>

        <intent-filter>
            <action android:name="android.intent.action.MAIN"/>
            <action android:name="com.example.test.testActivity"/>
            <category android:name="android.intent.category.LAUNCHER"/>
        </intent-filter>  

with this,

<activity android:name=".testActivity">

                <intent-filter>
                    <action android:name="android.intent.action.MAIN"/>
                    <action android:name="com.example.test.testActivity"/>
                    <category android:name="android.intent.category.LAUNCHER"/>
                </intent-filter>
        </activity>