使用AppCompat支持库的自定义工具栏不显示后退按钮

Question

i am working in a project where i need a custom toolbar as actionBar. i tried to use a custom toolbar in my layout file and define that activity theme as noActionBar in manifest file and use getSupportActionBar().setHomeButtonEnabled(true); i also used getSupportActionBar().setDisplayShowHomeEnabled(true); and getSupportActionBar().setDefaultDisplayHomeAsUpEnabled(true); but it didn't show up back button for me. then i also added android:parentActivityName=".MainActivity in my activity section in manifest file. still back button didn't show up.

here is my main activity file.

public class MainActivity extends AppCompatActivity {

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

   public void next(View view) {
      startActivity(new Intent(this, Main2Activity.class));
   }
}

activity_main.xml file:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
   xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:tools="http://schemas.android.com/tools"
   android:id="@+id/activity_main"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context="com.example.takmilul.actionbar.MainActivity">

   <Button
      android:id="@+id/next"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:layout_marginTop="40dp"
      android:onClick="next"
      android:text="Next"/>

</LinearLayout>

Main2Activity file:

public class Main2Activity extends AppCompatActivity {

   @Override
   protected void onCreate(Bundle savedInstanceState) {
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_main2);

      Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
      setSupportActionBar(toolbar);
      ActionBar actionBar = getSupportActionBar();
      getSupportActionBar().setDisplayShowHomeEnabled(true);
      getSupportActionBar().setHomeButtonEnabled(true);
      getSupportActionBar().setDefaultDisplayHomeAsUpEnabled(true);
      actionBar.setTitle("Second Activity");
   }
}

activity_main2.xml file:

<LinearLayout
   xmlns:android="http://schemas.android.com/apk/res/android"
   xmlns:app="http://schemas.android.com/apk/res-auto"
   xmlns:tools="http://schemas.android.com/tools"
   android:id="@+id/activity_main2"
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   tools:context="com.example.takmilul.actionbar.Main2Activity">

   <android.support.v7.widget.Toolbar
      android:id="@+id/toolbar"
      android:layout_width="match_parent"
      android:layout_height="wrap_content"
      android:background="@color/colorPrimary"
      app:theme="@style/ThemeOverlay.AppCompat.Dark">

   </android.support.v7.widget.Toolbar>
</LinearLayout>

styles.xml file:

<resources>
   <style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
      <item name="colorPrimary">@color/colorPrimary</item>
      <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
      <item name="colorAccent">@color/colorAccent</item>
   </style>

</resources>

AndroidManifest.xml file

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

   <application
      android:allowBackup="true"
      android:icon="@mipmap/ic_launcher"
      android:label="@string/app_name"
      android:supportsRtl="true"
      android:theme="@style/AppTheme">
      <activity android:name=".MainActivity">
         <intent-filter>
            <action android:name="android.intent.action.MAIN"/>

            <category android:name="android.intent.category.LAUNCHER"/>
         </intent-filter>
      </activity>
      <activity android:name=".Main2Activity"
         android:parentActivityName=".MainActivity"
         android:theme="@style/Theme.AppCompat.Light.NoActionBar">
         <meta-data
            android:name="android.support.PARENT_ACTIVITY"
            android:value=".MainActivity" />
      </activity>
   </application>

</manifest>

and the build.gradle file like:

apply plugin: 'com.android.application'

android {
    compileSdkVersion 23
    buildToolsVersion "23.0.3"
    defaultConfig {
        applicationId "com.example.takmilul.actionbar"
        minSdkVersion 16
        targetSdkVersion 23
        versionCode 1
        versionName "1.0"
        testInstrumentationRunner     "android.support.test.runner.AndroidJUnitRunner"
    }
    buildTypes {
        release {
            minifyEnabled false
            proguardFiles getDefaultProguardFile('proguard-android.txt'), 'proguard-rules.pro'
        }
    }
}

dependencies {
    compile fileTree(dir: 'libs', include: ['*.jar'])
    compile 'com.android.support:appcompat-v7:23.4.0'
}

please help me to show up the back button and go to the previous page at pressing that back button.

Answer 1

you have not set icon for back button. set a navigation icon for it. you can set it by xml file or java file. in xml file add line

app:navigationIcon="?attr/homeAsUpIndicator"

or in java file

getSupportActionBar().setHomeAsUpIndicator(getResources().getDrawable(R.drawable.abc_ic_ab_back_mtrl_am_alpha);

hope it works for you.

Answer 2

Just create a button in your activity_main2.xml file:

    <LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_main2"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context="com.example.takmilul.actionbar.Main2Activity">

<android.support.v7.widget.Toolbar
    android:id="@+id/toolbar"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/colorPrimary"
    app:theme="@style/ThemeOverlay.AppCompat.Dark">

    <Button
        android:id="@+id/back"
        android:layout_width="30sp"
        android:layout_height="30sp"
        android:background="@drawable/back_arrow"
        android:layout_marginLeft="10dp"
        android:onClick="back"/>

</android.support.v7.widget.Toolbar>

And Main2Activity file:

public class Main2Activity extends AppCompatActivity {


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

    Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);
    ActionBar actionBar = getSupportActionBar();
    getSupportActionBar().setDisplayShowHomeEnabled(true);
    getSupportActionBar().setHomeButtonEnabled(true);
    getSupportActionBar().setDefaultDisplayHomeAsUpEnabled(true);
    actionBar.setTitle("Second Activity");
    }

public void back(View view) {
   finish();
   }
   }

Answer 3

package com.example.saloni;

import android.os.Bundle;

import android.support.v7.app.AppCompatActivity;

import android.support.v7.widget.Toolbar;

public class Main2Activity extends AppCompatActivity {

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.fhg);
    setToolbar();  
    }
    private void setToolbar() {
    setSupportActionBar(((Toolbar) findViewById(R.id.toolbar)));        
    getSupportActionBar().setHomeButtonEnabled(true);
    getSupportActionBar().setHomeAsUpIndicator(R.drawable.back);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
}

}

Answer 4

<style name="AppTheme" parent="Theme.AppCompat.Light.DarkActionBar">
    <!-- Customize your theme here. -->
    <item name="windowNoTitle">true</item>
    <item name="windowActionBar">false</item>
    <item name="colorPrimary">@color/colorPrimary</item>
    <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
    <item name="colorAccent">@color/colorAccent</item>
    <item name="android:textColorPrimary">#FFFFFF</item>
</style>