android:logo

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

<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:logo="@mipmap/twitter"
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>
</application>

</manifest>

package com.pingyijinren.helloworld;

import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;

public class MainActivity extends AppCompatActivity {
private Button button;
private ActionBar actionBar;

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

actionBar = getSupportActionBar();
actionBar.setDisplayShowHomeEnabled(true);
actionBar.setLogo(R.mipmap.twitter);
actionBar.setDisplayUseLogoEnabled(true);

button=(Button)findViewById(R.id.button);
button.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(actionBar.isShowing()){
actionBar.hide();
}
else{
actionBar.show();
}
}
});
}
}