我在 Android studio 中有一个页面，我正在尝试在里面进行网站展示。 但问题是，我尝试从顶部将自定义地址放入地址栏中，但代码中出现错误，并附有注释“我认为相同的代码可以在其他类中工作，并且其他类中的一切都正确”。 但在这段代码中，有一个错误。
public class teamsnews extends AppCompatActivity {
private Toolbar toolbar;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_teamsnews);
WebView htmlWebView = (WebView)findViewById(R.id.webView);
// htmlWebView.setWebViewClient(new CustomWebViewClient());
WebSettings webSetting = htmlWebView.getSettings();
webSetting.setJavaScriptEnabled(true);
webSetting.setDisplayZoomControls(true);
htmlWebView.loadUrl("https://www.yallakora.com/Match-Center/%D9%85%D8%B1%D9%83%D8%B2-%D8%A7%D9%84%D9%85%D8%A8%D8%A7%D8%B1%D9%8A%D8%A7%D8%AA#nav-burgermenu");
SetupToolBar();
}
private void SetupToolBar() {
toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setTitle("");
TextView textView = findViewById(R.id.toolbar_title);
textView.setText("الدورى والبطولات");
}
}
//manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
package="com.otherHand">
<uses-permission android:name="android.permission.CALL_PHONE" />
<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
android:name=".utility.FirebaseOffline"
android:allowBackup="true"
android:icon="@drawable/logoy"
android:label="@string/app_name"
android:supportsRtl="false"
android:theme="@style/AppTheme"
tools:replace="android:supportsRtl">
<activity android:name=".teamsnews"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".Act_tutoriial"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar"/>
<activity
android:name=".DawraElramadnia"
android:launchMode="singleTop"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar"/>
<activity
android:name=".SplashScreen"
android:launchMode="singleTop"
android:theme="@style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<meta-data
android:name="com.google.android.gms.version"
android:value="@integer/google_play_services_version" /> <!-- > for notification handler<! -->
<meta-data
android:name="com.onesignal.NotificationOpened.DEFAULT"
android:value="DISABLE" />
<activity android:name="com.soundcloud.android.crop.CropImageActivity" />
<activity
android:name=".utility.TutorialActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".MainActivity"
android:launchMode="singleTop"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".DetailsActivity"
android:launchMode="singleTop"
android:parentActivityName=".MainActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".CommentActivity"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".ReservationActivity"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".utility.AddStudiam"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".CombineTeam"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
<activity
android:name=".GiftsAcivity"
android:launchMode="singleTop"
android:parentActivityName=".DetailsActivity"
android:screenOrientation="portrait"
android:theme="@style/AppTheme.NoActionBar" />
</application>
</manifest>
/// style
<resources>
<!-- Base application theme. -->
<style name="AppTheme"
parent="Theme.AppCompat.Light.DarkActionBar">
<!-- Customize your theme here. -->
<item name="colorPrimary">@color/colorPrimary</item>
<item name="colorPrimaryDark">@color/colorPrimaryDark</item>
<item name="colorAccent">@color/colorAccent</item>
<item name="android:windowNoTitle">true</item>
<item name="android:windowActionBar">false</item>
<item name="android:windowFullscreen">true</item>
<item name="android:windowContentOverlay">@null</item>
</style>
<style name="NoActionBarTheme"
parent="Theme.AppCompat.Light.NoActionBar"
/>
<style name="myRatingBar"
parent="@style/Base.Widget.AppCompat.RatingBar.Small">
</style>
<style name="CustomRatingBar"
parent="@android:style/Widget.Holo.RatingBar.Indicator">
<item name="android:progressDrawable">@drawable/ratingbar</item>
<item name="android:maxHeight">32dp</item>
</style>
<style name="CustomRatingBar2"
parent="@android:style/Widget.Holo.RatingBar.Indicator">
<item name="android:progressDrawable">@drawable/ratingbar_yellow</item>
<item name="android:maxHeight">32dp</item>
</style>
<!-->
!-->
<style name="AppTheme.NoActionBar">
<item name="windowActionBar">false</item>
<item name="windowNoTitle">true</item>
<item name="android:windowFullscreen">true</item>
</style>
<style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />
<style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />
<style name="CustomRatingBarsmall"
parent="@android:style/Widget.Holo.RatingBar.Small">
<item name="android:progressDrawable">@drawable/ratingbarsmall</item>
</style>
<style name="ToolbarTheme" parent="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<!-- android:textColorPrimary is the color of the title text in the Toolbar -->
<item name="android:textColorPrimary">@android:color/holo_blue_light</item>
<!-- actionMenuTextColor is the color of the text of action (menu) items -->
<item name="actionMenuTextColor">@android:color/holo_green_light</item>
<!-- Tints the input fields like checkboxes and text fields -->
<!-- Enable these below if you want clicking icons to trigger a ripple effect -->
<!--
<item name="selectableItemBackground">?android:selectableItemBackground</item>
<item name="selectableItemBackgroundBorderless">?android:selectableItemBackground</item>
-->
</style>
<!-- This configures the styles for the title within the Toolbar -->
<style name="Toolbar.TitleText" parent="TextAppearance.Widget.AppCompat.Toolbar.Title">
<item name="android:textSize">21sp</item>
<item name="android:textStyle">italic</item>
</style>
</resources>
// -------- Logecat error:
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.otherHand.mal3abak/com.otherHand.teamsnews}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.setDisplayHomeAsUpEnabled(boolean)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2695)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2769)
at android.app.ActivityThread.access$900(ActivityThread.java:177)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1430)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5910)
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:1405)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1200)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.setDisplayHomeAsUpEnabled(boolean)' on a null object reference
at com.otherHand.teamsnews.SetupToolBar(teamsnews.java:33)
at com.otherHand.teamsnews.onCreate(teamsnews.java:27)
at android.app.Activity.performCreate(Activity.java:6178)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
最佳答案
我认为您需要做的是将您设置的 TextView 文本用作 getSupportActionBar().setTitle() 函数中所需的文本。如果不使用为什么要设置为空？ Look at this和 The docs for setTitle .
关于java - 无法设置带有文本标题的工具栏？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/55943680/