supportActionBar is null using Kotlin Android always

Question

Just now google has made the Kotlin as an official programming language, so started converting my files to Kotlin.

While converting my code, I am always getting null pointer exception when I try to use supportActionBar

    // set up action bar
    setSupportActionBar(mToolbar)
    supportActionBar!!.setDisplayShowTitleEnabled(false)

    // set the hamburger menu
    supportActionBar!!.setDisplayHomeAsUpEnabled(true)
    supportActionBar!!.setHomeButtonEnabled(true)

My AndroidManifest entry is

      <activity android:name=".activities.MainActivity"
        android:screenOrientation="portrait"
        android:theme="@style/AppTheme.NoActionBar />

No actionbar is having windowActionBar as false. Every time I run the app, i get the null pointer exception whiel accessing the supportActionBar. Can anyone help me about it?

Did you forget to `setContentView`? It's hard to tell when you don't post the whole onCreate. — Eugen Pechanec, May 24 '17 at 07:03
Maybe you are wrong. @EugenPechanec. Go to this link -https://medium.com/@juanchosaravia/learn-kotlin-while-developing-an-android-app-part-1-e0f51fc1a8b3 In MainActivity.kt file clearly it is mentioned. — Sneha Sarkar, May 24 '17 at 07:08
Added the kotlin extension and directly using the toolbar. It is working now... Thanks people — DevAnuragGarg, May 25 '17 at 04:38
@CodeBoyChd ... could u help me plz . My setSupportActionBar is not recognizing — Ravindra Kushwaha, Aug 04 '17 at 10:47

score 5 · Answer 1 · edited Aug 31 '18 at 07:12

5

You can try

supportActionBar?.hide()

edited Aug 31 '18 at 07:12

Rupesh Agrawal

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answered Aug 31 '18 at 06:22

tj_

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1

While this might answer the authors question, it lacks some explaining words and links to documentation. Raw code snippets are not very helpful without some phrases around it. You may also find [how to write a good answer](https://stackoverflow.com/help/how-to-answer) very helpful. Please edit your answer. – hellow Aug 31 '18 at 06:27

score 4 · Answer 2 · answered May 24 '17 at 07:14

4

Have you initialised mToolbar with its view id? If not then make it like this and check.

var mToolbar = findViewById(R.id.toolbar) as Toolbar?
setSupportActionBar(mToolbar)

answered May 24 '17 at 07:14

Maddy

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Added the kotlin extension and directly using the toolbar. It is working now... Thanks people – DevAnuragGarg May 25 '17 at 04:37
@Maddy..Could u help me..My setSupportActionBar is not recognizing ?.What should i do now> – Ravindra Kushwaha Aug 04 '17 at 10:46
@RavindraKushwaha, extend your current activity by AppCompatActivity and set style of your activity as "Theme.AppCompat.Light.NoActionBar" – Maddy Aug 04 '17 at 12:15
Thanks for ur comment..I am using the library which is extending the `FragmentActivity` .. – Ravindra Kushwaha Aug 04 '17 at 12:32
@RavindraKushwaha, change it to AppCompatActivity if you can – Maddy Aug 04 '17 at 12:42

supportActionBar is null using Kotlin Android always

2 Answers2